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Diffstat (limited to 'thirdparty/stb/stb_voxel_render.h')
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diff --git a/thirdparty/stb/stb_voxel_render.h b/thirdparty/stb/stb_voxel_render.h new file mode 100644 index 0000000..514ed99 --- /dev/null +++ b/thirdparty/stb/stb_voxel_render.h @@ -0,0 +1,3803 @@ +// stb_voxel_render.h - v0.85 - Sean Barrett, 2015 - public domain +// +// This library helps render large-scale "voxel" worlds for games, +// in this case, one with blocks that can have textures and that +// can also be a few shapes other than cubes. +// +// Video introduction: +// http://www.youtube.com/watch?v=2vnTtiLrV1w +// +// Minecraft-viewer sample app (not very simple though): +// http://github.com/nothings/stb/tree/master/tests/caveview +// +// It works by creating triangle meshes. The library includes +// +// - converter from dense 3D arrays of block info to vertex mesh +// - vertex & fragment shaders for the vertex mesh +// - assistance in setting up shader state +// +// For portability, none of the library code actually accesses +// the 3D graphics API. (At the moment, it's not actually portable +// since the shaders are GLSL only, but patches are welcome.) +// +// You have to do all the caching and tracking of vertex buffers +// yourself. However, you could also try making a game with +// a small enough world that it's fully loaded rather than +// streaming. Currently the preferred vertex format is 20 bytes +// per quad. There are designs to allow much more compact formats +// with a slight reduction in shader features, but no roadmap +// for actually implementing them. +// +// +// USAGE +// +// #define the symbol STB_VOXEL_RENDER_IMPLEMENTATION in *one* +// C/C++ file before the #include of this file; the implementation +// will be generated in that file. +// +// If you define the symbols STB_VOXEL_RENDER_STATIC, then the +// implementation will be private to that file. +// +// +// FEATURES +// +// - you can choose textured blocks with the features below, +// or colored voxels with 2^24 colors and no textures. +// +// - voxels are mostly just cubes, but there's support for +// half-height cubes and diagonal slopes, half-height +// diagonals, and even odder shapes especially for doing +// more-continuous "ground". +// +// - texture coordinates are projections along one of the major +// axes, with the per-texture scaling. +// +// - a number of aspects of the shader and the vertex format +// are configurable; the library generally takes care of +// coordinating the vertex format with the mesh for you. +// +// +// FEATURES (SHADER PERSPECTIVE) +// +// - vertices aligned on integer lattice, z on multiples of 0.5 +// - per-vertex "lighting" or "ambient occlusion" value (6 bits) +// - per-vertex texture crossfade (3 bits) +// +// - per-face texture #1 id (8-bit index into array texture) +// - per-face texture #2 id (8-bit index into second array texture) +// - per-face color (6-bit palette index, 2 bits of per-texture boolean enable) +// - per-face 5-bit normal for lighting calculations & texture coord computation +// - per-face 2-bit texture matrix rotation to rotate faces +// +// - indexed-by-texture-id scale factor (separate for texture #1 and texture #2) +// - indexed-by-texture-#2-id blend mode (alpha composite or modulate/multiply); +// the first is good for decals, the second for detail textures, "light maps", +// etc; both modes are controlled by texture #2's alpha, scaled by the +// per-vertex texture crossfade and the per-face color (if enabled on texture #2); +// modulate/multiply multiplies by an extra factor of 2.0 so that if you +// make detail maps whose average brightness is 0.5 everything works nicely. +// +// - ambient lighting: half-lambert directional plus constant, all scaled by vertex ao +// - face can be fullbright (emissive), controlled by per-face color +// - installable lighting, with default single-point-light +// - installable fog, with default hacked smoothstep +// +// Note that all the variations of lighting selection and texture +// blending are run-time conditions in the shader, so they can be +// intermixed in a single mesh. +// +// +// INTEGRATION ARC +// +// The way to get this library to work from scratch is to do the following: +// +// Step 1. define STBVOX_CONFIG_MODE to 0 +// +// This mode uses only vertex attributes and uniforms, and is easiest +// to get working. It requires 32 bytes per quad and limits the +// size of some tables to avoid hitting uniform limits. +// +// Step 2. define STBVOX_CONFIG_MODE to 1 +// +// This requires using a texture buffer to store the quad data, +// reducing the size to 20 bytes per quad. +// +// Step 3: define STBVOX_CONFIG_PREFER_TEXBUFFER +// +// This causes some uniforms to be stored as texture buffers +// instead. This increases the size of some of those tables, +// and avoids a potential slow path (gathering non-uniform +// data from uniforms) on some hardware. +// +// In the future I might add additional modes that have significantly +// smaller meshes but reduce features, down as small as 6 bytes per quad. +// See elsewhere in this file for a table of candidate modes. Switching +// to a mode will require changing some of your mesh creation code, but +// everything else should be seamless. (And I'd like to change the API +// so that mesh creation is data-driven the way the uniforms are, and +// then you wouldn't even have to change anything but the mode number.) +// +// +// IMPROVEMENTS FOR SHIP-WORTHY PROGRAMS USING THIS LIBRARY +// +// I currently tolerate a certain level of "bugginess" in this library. +// +// I'm referring to things which look a little wrong (as long as they +// don't cause holes or cracks in the output meshes), or things which +// do not produce as optimal a mesh as possible. Notable examples: +// +// - incorrect lighting on slopes +// - inefficient meshes for vheight blocks +// +// I am willing to do the work to improve these things if someone is +// going to ship a substantial program that would be improved by them. +// (It need not be commercial, nor need it be a game.) I just didn't +// want to do the work up front if it might never be leveraged. So just +// submit a bug report as usual (github is preferred), but add a note +// that this is for a thing that is really going to ship. (That means +// you need to be far enough into the project that it's clear you're +// committed to it; not during early exploratory development.) +// +// +// VOXEL MESH API +// +// Context +// +// To understand the API, make sure you first understand the feature set +// listed above. +// +// Because the vertices are compact, they have very limited spatial +// precision. Thus a single mesh can only contain the data for a limited +// area. To make very large voxel maps, you'll need to build multiple +// vertex buffers. (But you want this anyway for frustum culling.) +// +// Each generated mesh has three components: +// - vertex data (vertex buffer) +// - face data (optional, stored in texture buffer) +// - mesh transform (uniforms) +// +// Once you've generated the mesh with this library, it's up to you +// to upload it to the GPU, to keep track of the state, and to render +// it. +// +// Concept +// +// The basic design is that you pass in one or more 3D arrays; each array +// is (typically) one-byte-per-voxel and contains information about one +// or more properties of some particular voxel property. +// +// Because there is so much per-vertex and per-face data possible +// in the output, and each voxel can have 6 faces and 8 vertices, it +// would require an very large data structure to describe all +// of the possibilities, and this would cause the mesh-creation +// process to be slow. Instead, the API provides multiple ways +// to express each property, some more compact, others less so; +// each such way has some limitations on what it can express. +// +// Note that there are so many paths and combinations, not all of them +// have been tested. Just report bugs and I'll fix 'em. +// +// Details +// +// See the API documentation in the header-file section. +// +// +// CONTRIBUTORS +// +// Features Porting Bugfixes & Warnings +// Sean Barrett github:r-leyh Jesus Fernandez +// Miguel Lechon github:Arbeiterunfallversicherungsgesetz +// Thomas Frase James Hofmann +// Stephen Olsen github:guitarfreak +// +// VERSION HISTORY +// +// 0.85 (2017-03-03) add block_selector (by guitarfreak) +// 0.84 (2016-04-02) fix GLSL syntax error on glModelView path +// 0.83 (2015-09-13) remove non-constant struct initializers to support more compilers +// 0.82 (2015-08-01) added input.packed_compact to store rot, vheight & texlerp efficiently +// fix broken tex_overlay2 +// 0.81 (2015-05-28) fix broken STBVOX_CONFIG_OPTIMIZED_VHEIGHT +// 0.80 (2015-04-11) fix broken STBVOX_CONFIG_ROTATION_IN_LIGHTING refactoring +// change STBVOX_MAKE_LIGHTING to STBVOX_MAKE_LIGHTING_EXT so +// that header defs don't need to see config vars +// add STBVOX_CONFIG_VHEIGHT_IN_LIGHTING and other vheight fixes +// added documentation for vheight ("weird slopes") +// 0.79 (2015-04-01) fix the missing types from 0.78; fix string constants being const +// 0.78 (2015-04-02) bad "#else", compile as C++ +// 0.77 (2015-04-01) documentation tweaks, rename config var to STB_VOXEL_RENDER_STATIC +// 0.76 (2015-04-01) typos, signed/unsigned shader issue, more documentation +// 0.75 (2015-04-01) initial release +// +// +// HISTORICAL FOUNDATION +// +// stb_voxel_render 20-byte quads 2015/01 +// zmc engine 32-byte quads 2013/12 +// zmc engine 96-byte quads 2011/10 +// +// +// LICENSE +// +// See end of file for license information. + +#ifndef INCLUDE_STB_VOXEL_RENDER_H +#define INCLUDE_STB_VOXEL_RENDER_H + +#include <stdlib.h> + +typedef struct stbvox_mesh_maker stbvox_mesh_maker; +typedef struct stbvox_input_description stbvox_input_description; + +#ifdef STB_VOXEL_RENDER_STATIC +#define STBVXDEC static +#else +#define STBVXDEC extern +#endif + +#ifdef __cplusplus +extern "C" { +#endif + +////////////////////////////////////////////////////////////////////////////// +// +// CONFIGURATION MACROS +// +// #define STBVOX_CONFIG_MODE <integer> // REQUIRED +// Configures the overall behavior of stb_voxel_render. This +// can affect the shaders, the uniform info, and other things. +// (If you need more than one mode in the same app, you can +// use STB_VOXEL_RENDER_STATIC to create multiple versions +// in separate files, and then wrap them.) +// +// Mode value Meaning +// 0 Textured blocks, 32-byte quads +// 1 Textured blocks, 20-byte quads +// 20 Untextured blocks, 32-byte quads +// 21 Untextured blocks, 20-byte quads +// +// +// #define STBVOX_CONFIG_PRECISION_Z <integer> // OPTIONAL +// Defines the number of bits of fractional position for Z. +// Only 0 or 1 are valid. 1 is the default. If 0, then a +// single mesh has twice the legal Z range; e.g. in +// modes 0,1,20,21, Z in the mesh can extend to 511 instead +// of 255. However, half-height blocks cannot be used. +// +// All of the following are just #ifdef tested so need no values, and are optional. +// +// STBVOX_CONFIG_BLOCKTYPE_SHORT +// use unsigned 16-bit values for 'blocktype' in the input instead of 8-bit values +// +// STBVOX_CONFIG_OPENGL_MODELVIEW +// use the gl_ModelView matrix rather than the explicit uniform +// +// STBVOX_CONFIG_HLSL +// NOT IMPLEMENTED! Define HLSL shaders instead of GLSL shaders +// +// STBVOX_CONFIG_PREFER_TEXBUFFER +// Stores many of the uniform arrays in texture buffers intead, +// so they can be larger and may be more efficient on some hardware. +// +// STBVOX_CONFIG_LIGHTING_SIMPLE +// Creates a simple lighting engine with a single point light source +// in addition to the default half-lambert ambient light. +// +// STBVOX_CONFIG_LIGHTING +// Declares a lighting function hook; you must append a lighting function +// to the shader before compiling it: +// vec3 compute_lighting(vec3 pos, vec3 norm, vec3 albedo, vec3 ambient); +// 'ambient' is the half-lambert ambient light with vertex ambient-occlusion applied +// +// STBVOX_CONFIG_FOG_SMOOTHSTEP +// Defines a simple unrealistic fog system designed to maximize +// unobscured view distance while not looking too weird when things +// emerge from the fog. Configured using an extra array element +// in the STBVOX_UNIFORM_ambient uniform. +// +// STBVOX_CONFIG_FOG +// Defines a fog function hook; you must append a fog function to +// the shader before compiling it: +// vec3 compute_fog(vec3 color, vec3 relative_pos, float fragment_alpha); +// "color" is the incoming pre-fogged color, fragment_alpha is the alpha value, +// and relative_pos is the vector from the point to the camera in worldspace +// +// STBVOX_CONFIG_DISABLE_TEX2 +// This disables all processing of texture 2 in the shader in case +// you don't use it. Eventually this could be replaced with a mode +// that omits the unused data entirely. +// +// STBVOX_CONFIG_TEX1_EDGE_CLAMP +// STBVOX_CONFIG_TEX2_EDGE_CLAMP +// If you want to edge clamp the textures, instead of letting them wrap, +// set this flag. By default stb_voxel_render relies on texture wrapping +// to simplify texture coordinate generation. This flag forces it to do +// it correctly, although there can still be minor artifacts. +// +// STBVOX_CONFIG_ROTATION_IN_LIGHTING +// Changes the meaning of the 'lighting' mesher input variable to also +// store the rotation; see later discussion. +// +// STBVOX_CONFIG_VHEIGHT_IN_LIGHTING +// Changes the meaning of the 'lighting' mesher input variable to also +// store the vheight; see later discussion. Cannot use both this and +// the previous variable. +// +// STBVOX_CONFIG_PREMULTIPLIED_ALPHA +// Adjusts the shader calculations on the assumption that tex1.rgba, +// tex2.rgba, and color.rgba all use premultiplied values, and that +// the output of the fragment shader should be premultiplied. +// +// STBVOX_CONFIG_UNPREMULTIPLY +// Only meaningful if STBVOX_CONFIG_PREMULTIPLIED_ALPHA is defined. +// Changes the behavior described above so that the inputs are +// still premultiplied alpha, but the output of the fragment +// shader is not premultiplied alpha. This is needed when allowing +// non-unit alpha values but not doing alpha-blending (for example +// when alpha testing). +// + +////////////////////////////////////////////////////////////////////////////// +// +// MESHING +// +// A mesh represents a (typically) small chunk of a larger world. +// Meshes encode coordinates using small integers, so those +// coordinates must be relative to some base location. +// All of the coordinates in the functions below use +// these relative coordinates unless explicitly stated +// otherwise. +// +// Input to the meshing step is documented further down + +STBVXDEC void stbvox_init_mesh_maker(stbvox_mesh_maker *mm); +// Call this function to initialize a mesh-maker context structure +// used to build meshes. You should have one context per thread +// that's building meshes. + +STBVXDEC void stbvox_set_buffer(stbvox_mesh_maker *mm, int mesh, int slot, void *buffer, size_t len); +// Call this to set the buffer into which stbvox will write the mesh +// it creates. It can build more than one mesh in parallel (distinguished +// by the 'mesh' parameter), and each mesh can be made up of more than +// one buffer (distinguished by the 'slot' parameter). +// +// Multiple meshes are under your control; use the 'selector' input +// variable to choose which mesh each voxel's vertices are written to. +// For example, you can use this to generate separate meshes for opaque +// and transparent data. +// +// You can query the number of slots by calling stbvox_get_buffer_count +// described below. The meaning of the buffer for each slot depends +// on STBVOX_CONFIG_MODE. +// +// In mode 0 & mode 20, there is only one slot. The mesh data for that +// slot is two interleaved vertex attributes: attr_vertex, a single +// 32-bit uint, and attr_face, a single 32-bit uint. +// +// In mode 1 & mode 21, there are two slots. The first buffer should +// be four times as large as the second buffer. The first buffer +// contains a single vertex attribute: 'attr_vertex', a single 32-bit uint. +// The second buffer contains texture buffer data (an array of 32-bit uints) +// that will be accessed through the sampler identified by STBVOX_UNIFORM_face_data. + +STBVXDEC int stbvox_get_buffer_count(stbvox_mesh_maker *mm); +// Returns the number of buffers needed per mesh as described above. + +STBVXDEC int stbvox_get_buffer_size_per_quad(stbvox_mesh_maker *mm, int slot); +// Returns how much of a given buffer will get used per quad. This +// allows you to choose correct relative sizes for each buffer, although +// the values are fixed based on the configuration you've selected at +// compile time, and the details are described in stbvox_set_buffer. + +STBVXDEC void stbvox_set_default_mesh(stbvox_mesh_maker *mm, int mesh); +// Selects which mesh the mesher will output to (see previous function) +// if the input doesn't specify a per-voxel selector. (I doubt this is +// useful, but it's here just in case.) + +STBVXDEC stbvox_input_description *stbvox_get_input_description(stbvox_mesh_maker *mm); +// This function call returns a pointer to the stbvox_input_description part +// of stbvox_mesh_maker (which you should otherwise treat as opaque). You +// zero this structure, then fill out the relevant pointers to the data +// describing your voxel object/world. +// +// See further documentation at the description of stbvox_input_description below. + +STBVXDEC void stbvox_set_input_stride(stbvox_mesh_maker *mm, int x_stride_in_elements, int y_stride_in_elements); +// This sets the stride between successive elements of the 3D arrays +// in the stbvox_input_description. Z values are always stored consecutively. +// (The preferred coordinate system for stbvox is X right, Y forwards, Z up.) + +STBVXDEC void stbvox_set_input_range(stbvox_mesh_maker *mm, int x0, int y0, int z0, int x1, int y1, int z1); +// This sets the range of values in the 3D array for the voxels that +// the mesh generator will convert. The lower values are inclusive, +// the higher values are exclusive, so (0,0,0) to (16,16,16) generates +// mesh data associated with voxels up to (15,15,15) but no higher. +// +// The mesh generate generates faces at the boundary between open space +// and solid space but associates them with the solid space, so if (15,0,0) +// is open and (16,0,0) is solid, then the mesh will contain the boundary +// between them if x0 <= 16 and x1 > 16. +// +// Note that the mesh generator will access array elements 1 beyond the +// limits set in these parameters. For example, if you set the limits +// to be (0,0,0) and (16,16,16), then the generator will access all of +// the voxels between (-1,-1,-1) and (16,16,16), including (16,16,16). +// You may have to do pointer arithmetic to make it work. +// +// For example, caveview processes mesh chunks that are 32x32x16, but it +// does this using input buffers that are 34x34x18. +// +// The lower limits are x0 >= 0, y0 >= 0, and z0 >= 0. +// +// The upper limits are mode dependent, but all the current methods are +// limited to x1 < 127, y1 < 127, z1 < 255. Note that these are not +// powers of two; if you want to use power-of-two chunks (to make +// it efficient to decide which chunk a coordinate falls in), you're +// limited to at most x1=64, y1=64, z1=128. For classic Minecraft-style +// worlds with limited vertical extent, I recommend using a single +// chunk for the entire height, which limits the height to 255 blocks +// (one less than Minecraft), and only chunk the map in X & Y. + +STBVXDEC int stbvox_make_mesh(stbvox_mesh_maker *mm); +// Call this function to create mesh data for the currently configured +// set of input data. This appends to the currently configured mesh output +// buffer. Returns 1 on success. If there is not enough room in the buffer, +// it outputs as much as it can, and returns 0; you need to switch output +// buffers (either by calling stbvox_set_buffer to set new buffers, or +// by copying the data out and calling stbvox_reset_buffers), and then +// call this function again without changing any of the input parameters. +// +// Note that this function appends; you can call it multiple times to +// build a single mesh. For example, caveview uses chunks that are +// 32x32x255, but builds the mesh for it by processing 32x32x16 at atime +// (this is faster as it is reuses the same 34x34x18 input buffers rather +// than needing 34x34x257 input buffers). + +// Once you're done creating a mesh into a given buffer, +// consider the following functions: + +STBVXDEC int stbvox_get_quad_count(stbvox_mesh_maker *mm, int mesh); +// Returns the number of quads in the mesh currently generated by mm. +// This is the sum of all consecutive stbvox_make_mesh runs appending +// to the same buffer. 'mesh' distinguishes between the multiple user +// meshes available via 'selector' or stbvox_set_default_mesh. +// +// Typically you use this function when you're done building the mesh +// and want to record how to draw it. +// +// Note that there are no index buffers; the data stored in the buffers +// should be drawn as quads (e.g. with GL_QUAD); if your API does not +// support quads, you can create a single index buffer large enough to +// draw your largest vertex buffer, and reuse it for every rendering. +// (Note that if you use 32-bit indices, you'll use 24 bytes of bandwidth +// per quad, more than the 20 bytes for the vertex/face mesh data.) + +STBVXDEC void stbvox_set_mesh_coordinates(stbvox_mesh_maker *mm, int x, int y, int z); +// Sets the global coordinates for this chunk, such that (0,0,0) relative +// coordinates will be at (x,y,z) in global coordinates. + +STBVXDEC void stbvox_get_bounds(stbvox_mesh_maker *mm, float bounds[2][3]); +// Returns the bounds for the mesh in global coordinates. Use this +// for e.g. frustum culling the mesh. @BUG: this just uses the +// values from stbvox_set_input_range(), so if you build by +// appending multiple values, this will be wrong, and you need to +// set stbvox_set_input_range() to the full size. Someday this +// will switch to tracking the actual bounds of the *mesh*, though. + +STBVXDEC void stbvox_get_transform(stbvox_mesh_maker *mm, float transform[3][3]); +// Returns the 'transform' data for the shader uniforms. It is your +// job to set this to the shader before drawing the mesh. It is the +// only uniform that needs to change per-mesh. Note that it is not +// a 3x3 matrix, but rather a scale to decode fixed point numbers as +// floats, a translate from relative to global space, and a special +// translation for texture coordinate generation that avoids +// floating-point precision issues. @TODO: currently we add the +// global translation to the vertex, than multiply by modelview, +// but this means if camera location and vertex are far from the +// origin, we lose precision. Need to make a special modelview with +// the translation (or some of it) factored out to avoid this. + +STBVXDEC void stbvox_reset_buffers(stbvox_mesh_maker *mm); +// Call this function if you're done with the current output buffer +// but want to reuse it (e.g. you're done appending with +// stbvox_make_mesh and you've copied the data out to your graphics API +// so can reuse the buffer). + +////////////////////////////////////////////////////////////////////////////// +// +// RENDERING +// + +STBVXDEC char *stbvox_get_vertex_shader(void); +// Returns the (currently GLSL-only) vertex shader. + +STBVXDEC char *stbvox_get_fragment_shader(void); +// Returns the (currently GLSL-only) fragment shader. +// You can override the lighting and fogging calculations +// by appending data to the end of these; see the #define +// documentation for more information. + +STBVXDEC char *stbvox_get_fragment_shader_alpha_only(void); +// Returns a slightly cheaper fragment shader that computes +// alpha but not color. This is useful for e.g. a depth-only +// pass when using alpha test. + +typedef struct stbvox_uniform_info stbvox_uniform_info; + +STBVXDEC int stbvox_get_uniform_info(stbvox_uniform_info *info, int uniform); +// Gets the information about a uniform necessary for you to +// set up each uniform with a minimal amount of explicit code. +// See the sample code after the structure definition for stbvox_uniform_info, +// further down in this header section. +// +// "uniform" is from the list immediately following. For many +// of these, default values are provided which you can set. +// Most values are shared for most draw calls; e.g. for stateful +// APIs you can set most of the state only once. Only +// STBVOX_UNIFORM_transform needs to change per draw call. +// +// STBVOX_UNIFORM_texscale +// 64- or 128-long vec4 array. (128 only if STBVOX_CONFIG_PREFER_TEXBUFFER) +// x: scale factor to apply to texture #1. must be a power of two. 1.0 means 'face-sized' +// y: scale factor to apply to texture #2. must be a power of two. 1.0 means 'face-sized' +// z: blend mode indexed by texture #2. 0.0 is alpha compositing; 1.0 is multiplication. +// w: unused currently. @TODO use to support texture animation? +// +// Texscale is indexed by the bottom 6 or 7 bits of the texture id; thus for +// example the texture at index 0 in the array and the texture in index 128 of +// the array must be scaled the same. This means that if you only have 64 or 128 +// unique textures, they all get distinct values anyway; otherwise you have +// to group them in pairs or sets of four. +// +// STBVOX_UNIFORM_ambient +// 4-long vec4 array: +// ambient[0].xyz - negative of direction of a directional light for half-lambert +// ambient[1].rgb - color of light scaled by NdotL (can be negative) +// ambient[2].rgb - constant light added to above calculation; +// effectively light ranges from ambient[2]-ambient[1] to ambient[2]+ambient[1] +// ambient[3].rgb - fog color for STBVOX_CONFIG_FOG_SMOOTHSTEP +// ambient[3].a - reciprocal of squared distance of farthest fog point (viewing distance) + + + // +----- has a default value + // | +-- you should always use the default value +enum // V V +{ // ------------------------------------------------ + STBVOX_UNIFORM_face_data, // n the sampler with the face texture buffer + STBVOX_UNIFORM_transform, // n the transform data from stbvox_get_transform + STBVOX_UNIFORM_tex_array, // n an array of two texture samplers containing the two texture arrays + STBVOX_UNIFORM_texscale, // Y a table of texture properties, see above + STBVOX_UNIFORM_color_table, // Y 64 vec4 RGBA values; a default palette is provided; if A > 1.0, fullbright + STBVOX_UNIFORM_normals, // Y Y table of normals, internal-only + STBVOX_UNIFORM_texgen, // Y Y table of texgen vectors, internal-only + STBVOX_UNIFORM_ambient, // n lighting & fog info, see above + STBVOX_UNIFORM_camera_pos, // Y camera position in global voxel space (for lighting & fog) + + STBVOX_UNIFORM_count, +}; + +enum +{ + STBVOX_UNIFORM_TYPE_none, + STBVOX_UNIFORM_TYPE_sampler, + STBVOX_UNIFORM_TYPE_vec2, + STBVOX_UNIFORM_TYPE_vec3, + STBVOX_UNIFORM_TYPE_vec4, +}; + +struct stbvox_uniform_info +{ + int type; // which type of uniform + int bytes_per_element; // the size of each uniform array element (e.g. vec3 = 12 bytes) + int array_length; // length of the uniform array + char *name; // name in the shader @TODO use numeric binding + float *default_value; // if not NULL, you can use this as the uniform pointer + int use_tex_buffer; // if true, then the uniform is a sampler but the data can come from default_value +}; + +////////////////////////////////////////////////////////////////////////////// +// +// Uniform sample code +// + +#if 0 +// Run this once per frame before drawing all the meshes. +// You still need to separately set the 'transform' uniform for every mesh. +void setup_uniforms(GLuint shader, float camera_pos[4], GLuint tex1, GLuint tex2) +{ + int i; + glUseProgram(shader); // so uniform binding works + for (i=0; i < STBVOX_UNIFORM_count; ++i) { + stbvox_uniform_info sui; + if (stbvox_get_uniform_info(&sui, i)) { + GLint loc = glGetUniformLocation(shader, sui.name); + if (loc != 0) { + switch (i) { + case STBVOX_UNIFORM_camera_pos: // only needed for fog + glUniform4fv(loc, sui.array_length, camera_pos); + break; + + case STBVOX_UNIFORM_tex_array: { + GLuint tex_unit[2] = { 0, 1 }; // your choice of samplers + glUniform1iv(loc, 2, tex_unit); + + glActiveTexture(GL_TEXTURE0 + tex_unit[0]); glBindTexture(GL_TEXTURE_2D_ARRAY, tex1); + glActiveTexture(GL_TEXTURE0 + tex_unit[1]); glBindTexture(GL_TEXTURE_2D_ARRAY, tex2); + glActiveTexture(GL_TEXTURE0); // reset to default + break; + } + + case STBVOX_UNIFORM_face_data: + glUniform1i(loc, SAMPLER_YOU_WILL_BIND_PER_MESH_FACE_DATA_TO); + break; + + case STBVOX_UNIFORM_ambient: // you definitely want to override this + case STBVOX_UNIFORM_color_table: // you might want to override this + case STBVOX_UNIFORM_texscale: // you may want to override this + glUniform4fv(loc, sui.array_length, sui.default_value); + break; + + case STBVOX_UNIFORM_normals: // you never want to override this + case STBVOX_UNIFORM_texgen: // you never want to override this + glUniform3fv(loc, sui.array_length, sui.default_value); + break; + } + } + } + } +} +#endif + +#ifdef __cplusplus +} +#endif + +////////////////////////////////////////////////////////////////////////////// +// +// INPUT TO MESHING +// + +// Shapes of blocks that aren't always cubes +enum +{ + STBVOX_GEOM_empty, + STBVOX_GEOM_knockout, // creates a hole in the mesh + STBVOX_GEOM_solid, + STBVOX_GEOM_transp, // solid geometry, but transparent contents so neighbors generate normally, unless same blocktype + + // following 4 can be represented by vheight as well + STBVOX_GEOM_slab_upper, + STBVOX_GEOM_slab_lower, + STBVOX_GEOM_floor_slope_north_is_top, + STBVOX_GEOM_ceil_slope_north_is_bottom, + + STBVOX_GEOM_floor_slope_north_is_top_as_wall_UNIMPLEMENTED, // same as floor_slope above, but uses wall's texture & texture projection + STBVOX_GEOM_ceil_slope_north_is_bottom_as_wall_UNIMPLEMENTED, + STBVOX_GEOM_crossed_pair, // corner-to-corner pairs, with normal vector bumped upwards + STBVOX_GEOM_force, // like GEOM_transp, but faces visible even if neighbor is same type, e.g. minecraft fancy leaves + + // these access vheight input + STBVOX_GEOM_floor_vheight_03 = 12, // diagonal is SW-NE + STBVOX_GEOM_floor_vheight_12, // diagonal is SE-NW + STBVOX_GEOM_ceil_vheight_03, + STBVOX_GEOM_ceil_vheight_12, + + STBVOX_GEOM_count, // number of geom cases +}; + +enum +{ + STBVOX_FACE_east, + STBVOX_FACE_north, + STBVOX_FACE_west, + STBVOX_FACE_south, + STBVOX_FACE_up, + STBVOX_FACE_down, + + STBVOX_FACE_count, +}; + +#ifdef STBVOX_CONFIG_BLOCKTYPE_SHORT +typedef unsigned short stbvox_block_type; +#else +typedef unsigned char stbvox_block_type; +#endif + +// 24-bit color +typedef struct +{ + unsigned char r,g,b; +} stbvox_rgb; + +#define STBVOX_COLOR_TEX1_ENABLE 64 +#define STBVOX_COLOR_TEX2_ENABLE 128 + +// This is the data structure you fill out. Most of the arrays can be +// NULL, except when one is required to get the value to index another. +// +// The compass system used in the following descriptions is: +// east means increasing x +// north means increasing y +// up means increasing z +struct stbvox_input_description +{ + unsigned char lighting_at_vertices; + // The default is lighting values (i.e. ambient occlusion) are at block + // center, and the vertex light is gathered from those adjacent block + // centers that the vertex is facing. This makes smooth lighting + // consistent across adjacent faces with the same orientation. + // + // Setting this flag to non-zero gives you explicit control + // of light at each vertex, but now the lighting/ao will be + // shared by all vertices at the same point, even if they + // have different normals. + + // these are mostly 3D maps you use to define your voxel world, using x_stride and y_stride + // note that for cache efficiency, you want to use the block_foo palettes as much as possible instead + + stbvox_rgb *rgb; + // Indexed by 3D coordinate. + // 24-bit voxel color for STBVOX_CONFIG_MODE = 20 or 21 only + + unsigned char *lighting; + // Indexed by 3D coordinate. The lighting value / ambient occlusion + // value that is used to define the vertex lighting values. + // The raw lighting values are defined at the center of blocks + // (or at vertex if 'lighting_at_vertices' is true). + // + // If the macro STBVOX_CONFIG_ROTATION_IN_LIGHTING is defined, + // then an additional 2-bit block rotation value is stored + // in this field as well. + // + // Encode with STBVOX_MAKE_LIGHTING_EXT(lighting,rot)--here + // 'lighting' should still be 8 bits, as the macro will + // discard the bottom bits automatically. Similarly, if + // using STBVOX_CONFIG_VHEIGHT_IN_LIGHTING, encode with + // STBVOX_MAKE_LIGHTING_EXT(lighting,vheight). + // + // (Rationale: rotation needs to be independent of blocktype, + // but is only 2 bits so doesn't want to be its own array. + // Lighting is the one thing that was likely to already be + // in use and that I could easily steal 2 bits from.) + + stbvox_block_type *blocktype; + // Indexed by 3D coordinate. This is a core "block type" value, which is used + // to index into other arrays; essentially a "palette". This is much more + // memory-efficient and performance-friendly than storing the values explicitly, + // but only makes sense if the values are always synchronized. + // + // If a voxel's blocktype is 0, it is assumed to be empty (STBVOX_GEOM_empty), + // and no other blocktypes should be STBVOX_GEOM_empty. (Only if you do not + // have blocktypes should STBVOX_GEOM_empty ever used.) + // + // Normally it is an unsigned byte, but you can override it to be + // a short if you have too many blocktypes. + + unsigned char *geometry; + // Indexed by 3D coordinate. Contains the geometry type for the block. + // Also contains a 2-bit rotation for how the whole block is rotated. + // Also includes a 2-bit vheight value when using shared vheight values. + // See the separate vheight documentation. + // Encode with STBVOX_MAKE_GEOMETRY(geom, rot, vheight) + + unsigned char *block_geometry; + // Array indexed by blocktype containing the geometry for this block, plus + // a 2-bit "simple rotation". Note rotation has limited use since it's not + // independent of blocktype. + // + // Encode with STBVOX_MAKE_GEOMETRY(geom,simple_rot,0) + + unsigned char *block_tex1; + // Array indexed by blocktype containing the texture id for texture #1. + + unsigned char (*block_tex1_face)[6]; + // Array indexed by blocktype and face containing the texture id for texture #1. + // The N/E/S/W face choices can be rotated by one of the rotation selectors; + // The top & bottom face textures will rotate to match. + // Note that it only makes sense to use one of block_tex1 or block_tex1_face; + // this pattern repeats throughout and this notice is not repeated. + + unsigned char *tex2; + // Indexed by 3D coordinate. Contains the texture id for texture #2 + // to use on all faces of the block. + + unsigned char *block_tex2; + // Array indexed by blocktype containing the texture id for texture #2. + + unsigned char (*block_tex2_face)[6]; + // Array indexed by blocktype and face containing the texture id for texture #2. + // The N/E/S/W face choices can be rotated by one of the rotation selectors; + // The top & bottom face textures will rotate to match. + + unsigned char *color; + // Indexed by 3D coordinate. Contains the color for all faces of the block. + // The core color value is 0..63. + // Encode with STBVOX_MAKE_COLOR(color_number, tex1_enable, tex2_enable) + + unsigned char *block_color; + // Array indexed by blocktype containing the color value to apply to the faces. + // The core color value is 0..63. + // Encode with STBVOX_MAKE_COLOR(color_number, tex1_enable, tex2_enable) + + unsigned char (*block_color_face)[6]; + // Array indexed by blocktype and face containing the color value to apply to that face. + // The core color value is 0..63. + // Encode with STBVOX_MAKE_COLOR(color_number, tex1_enable, tex2_enable) + + unsigned char *block_texlerp; + // Array indexed by blocktype containing 3-bit scalar for texture #2 alpha + // (known throughout as 'texlerp'). This is constant over every face even + // though the property is potentially per-vertex. + + unsigned char (*block_texlerp_face)[6]; + // Array indexed by blocktype and face containing 3-bit scalar for texture #2 alpha. + // This is constant over the face even though the property is potentially per-vertex. + + unsigned char *block_vheight; + // Array indexed by blocktype containing the vheight values for the + // top or bottom face of this block. These will rotate properly if the + // block is rotated. See discussion of vheight. + // Encode with STBVOX_MAKE_VHEIGHT(sw_height, se_height, nw_height, ne_height) + + unsigned char *selector; + // Array indexed by 3D coordinates indicating which output mesh to select. + + unsigned char *block_selector; + // Array indexed by blocktype indicating which output mesh to select. + + unsigned char *side_texrot; + // Array indexed by 3D coordinates encoding 2-bit texture rotations for the + // faces on the E/N/W/S sides of the block. + // Encode with STBVOX_MAKE_SIDE_TEXROT(rot_e, rot_n, rot_w, rot_s) + + unsigned char *block_side_texrot; + // Array indexed by blocktype encoding 2-bit texture rotations for the faces + // on the E/N/W/S sides of the block. + // Encode with STBVOX_MAKE_SIDE_TEXROT(rot_e, rot_n, rot_w, rot_s) + + unsigned char *overlay; // index into palettes listed below + // Indexed by 3D coordinate. If 0, there is no overlay. If non-zero, + // it indexes into to the below arrays and overrides the values + // defined by the blocktype. + + unsigned char (*overlay_tex1)[6]; + // Array indexed by overlay value and face, containing an override value + // for the texture id for texture #1. If 0, the value defined by blocktype + // is used. + + unsigned char (*overlay_tex2)[6]; + // Array indexed by overlay value and face, containing an override value + // for the texture id for texture #2. If 0, the value defined by blocktype + // is used. + + unsigned char (*overlay_color)[6]; + // Array indexed by overlay value and face, containing an override value + // for the face color. If 0, the value defined by blocktype is used. + + unsigned char *overlay_side_texrot; + // Array indexed by overlay value, encoding 2-bit texture rotations for the faces + // on the E/N/W/S sides of the block. + // Encode with STBVOX_MAKE_SIDE_TEXROT(rot_e, rot_n, rot_w, rot_s) + + unsigned char *rotate; + // Indexed by 3D coordinate. Allows independent rotation of several + // parts of the voxel, where by rotation I mean swapping textures + // and colors between E/N/S/W faces. + // Block: rotates anything indexed by blocktype + // Overlay: rotates anything indexed by overlay + // EColor: rotates faces defined in ecolor_facemask + // Encode with STBVOX_MAKE_MATROT(block,overlay,ecolor) + + unsigned char *tex2_for_tex1; + // Array indexed by tex1 containing the texture id for texture #2. + // You can use this if the two are always/almost-always strictly + // correlated (e.g. if tex2 is a detail texture for tex1), as it + // will be more efficient (touching fewer cache lines) than using + // e.g. block_tex2_face. + + unsigned char *tex2_replace; + // Indexed by 3D coordinate. Specifies the texture id for texture #2 + // to use on a single face of the voxel, which must be E/N/W/S (not U/D). + // The texture id is limited to 6 bits unless tex2_facemask is also + // defined (see below). + // Encode with STBVOX_MAKE_TEX2_REPLACE(tex2, face) + + unsigned char *tex2_facemask; + // Indexed by 3D coordinate. Specifies which of the six faces should + // have their tex2 replaced by the value of tex2_replace. In this + // case, all 8 bits of tex2_replace are used as the texture id. + // Encode with STBVOX_MAKE_FACE_MASK(east,north,west,south,up,down) + + unsigned char *extended_color; + // Indexed by 3D coordinate. Specifies a value that indexes into + // the ecolor arrays below (both of which must be defined). + + unsigned char *ecolor_color; + // Indexed by extended_color value, specifies an optional override + // for the color value on some faces. + // Encode with STBVOX_MAKE_COLOR(color_number, tex1_enable, tex2_enable) + + unsigned char *ecolor_facemask; + // Indexed by extended_color value, this specifies which faces the + // color in ecolor_color should be applied to. The faces can be + // independently rotated by the ecolor value of 'rotate', if it exists. + // Encode with STBVOX_MAKE_FACE_MASK(e,n,w,s,u,d) + + unsigned char *color2; + // Indexed by 3D coordinates, specifies an alternative color to apply + // to some of the faces of the block. + // Encode with STBVOX_MAKE_COLOR(color_number, tex1_enable, tex2_enable) + + unsigned char *color2_facemask; + // Indexed by 3D coordinates, specifies which faces should use the + // color defined in color2. No rotation value is applied. + // Encode with STBVOX_MAKE_FACE_MASK(e,n,w,s,u,d) + + unsigned char *color3; + // Indexed by 3D coordinates, specifies an alternative color to apply + // to some of the faces of the block. + // Encode with STBVOX_MAKE_COLOR(color_number, tex1_enable, tex2_enable) + + unsigned char *color3_facemask; + // Indexed by 3D coordinates, specifies which faces should use the + // color defined in color3. No rotation value is applied. + // Encode with STBVOX_MAKE_FACE_MASK(e,n,w,s,u,d) + + unsigned char *texlerp_simple; + // Indexed by 3D coordinates, this is the smallest texlerp encoding + // that can do useful work. It consits of three values: baselerp, + // vertlerp, and face_vertlerp. Baselerp defines the value + // to use on all of the faces but one, from the STBVOX_TEXLERP_BASE + // values. face_vertlerp is one of the 6 face values (or STBVOX_FACE_NONE) + // which specifies the face should use the vertlerp values. + // Vertlerp defines a lerp value at every vertex of the mesh. + // Thus, one face can have per-vertex texlerp values, and those + // values are encoded in the space so that they will be shared + // by adjacent faces that also use vertlerp, allowing continuity + // (this is used for the "texture crossfade" bit of the release video). + // Encode with STBVOX_MAKE_TEXLERP_SIMPLE(baselerp, vertlerp, face_vertlerp) + + // The following texlerp encodings are experimental and maybe not + // that useful. + + unsigned char *texlerp; + // Indexed by 3D coordinates, this defines four values: + // vertlerp is a lerp value at every vertex of the mesh (using STBVOX_TEXLERP_BASE values). + // ud is the value to use on up and down faces, from STBVOX_TEXLERP_FACE values + // ew is the value to use on east and west faces, from STBVOX_TEXLERP_FACE values + // ns is the value to use on north and south faces, from STBVOX_TEXLERP_FACE values + // If any of ud, ew, or ns is STBVOX_TEXLERP_FACE_use_vert, then the + // vertlerp values for the vertices are gathered and used for those faces. + // Encode with STBVOX_MAKE_TEXLERP(vertlerp,ud,ew,sw) + + unsigned short *texlerp_vert3; + // Indexed by 3D coordinates, this works with texlerp and + // provides a unique texlerp value for every direction at + // every vertex. The same rules of whether faces share values + // applies. The STBVOX_TEXLERP_FACE vertlerp value defined in + // texlerp is only used for the down direction. The values at + // each vertex in other directions are defined in this array, + // and each uses the STBVOX_TEXLERP3 values (i.e. full precision + // 3-bit texlerp values). + // Encode with STBVOX_MAKE_VERT3(vertlerp_e,vertlerp_n,vertlerp_w,vertlerp_s,vertlerp_u) + + unsigned short *texlerp_face3; // e:3,n:3,w:3,s:3,u:2,d:2 + // Indexed by 3D coordinates, this provides a compact way to + // fully specify the texlerp value indepenendly for every face, + // but doesn't allow per-vertex variation. E/N/W/S values are + // encoded using STBVOX_TEXLERP3 values, whereas up and down + // use STBVOX_TEXLERP_SIMPLE values. + // Encode with STBVOX_MAKE_FACE3(face_e,face_n,face_w,face_s,face_u,face_d) + + unsigned char *vheight; // STBVOX_MAKE_VHEIGHT -- sw:2, se:2, nw:2, ne:2, doesn't rotate + // Indexed by 3D coordinates, this defines the four + // vheight values to use if the geometry is STBVOX_GEOM_vheight*. + // See the vheight discussion. + + unsigned char *packed_compact; + // Stores block rotation, vheight, and texlerp values: + // block rotation: 2 bits + // vertex vheight: 2 bits + // use_texlerp : 1 bit + // vertex texlerp: 3 bits + // If STBVOX_CONFIG_UP_TEXLERP_PACKED is defined, then 'vertex texlerp' is + // used for up faces if use_texlerp is 1. If STBVOX_CONFIG_DOWN_TEXLERP_PACKED + // is defined, then 'vertex texlerp' is used for down faces if use_texlerp is 1. + // Note if those symbols are defined but packed_compact is NULL, the normal + // texlerp default will be used. + // Encode with STBVOX_MAKE_PACKED_COMPACT(rot, vheight, texlerp, use_texlerp) +}; +// @OPTIMIZE allow specializing; build a single struct with all of the +// 3D-indexed arrays combined so it's AoS instead of SoA for better +// cache efficiency + + +////////////////////////////////////////////////////////////////////////////// +// +// VHEIGHT DOCUMENTATION +// +// "vheight" is the internal name for the special block types +// with sloped tops or bottoms. "vheight" stands for "vertex height". +// +// Note that these blocks are very flexible (there are 256 of them, +// although at least 17 of them should never be used), but they +// also have a disadvantage that they generate extra invisible +// faces; the generator does not currently detect whether adjacent +// vheight blocks hide each others sides, so those side faces are +// always generated. For a continuous ground terrain, this means +// that you may generate 5x as many quads as needed. See notes +// on "improvements for shipping products" in the introduction. + +enum +{ + STBVOX_VERTEX_HEIGHT_0, + STBVOX_VERTEX_HEIGHT_half, + STBVOX_VERTEX_HEIGHT_1, + STBVOX_VERTEX_HEIGHT_one_and_a_half, +}; +// These are the "vheight" values. Vheight stands for "vertex height". +// The idea is that for a "floor vheight" block, you take a cube and +// reposition the top-most vertices at various heights as specified by +// the vheight values. Similarly, a "ceiling vheight" block takes a +// cube and repositions the bottom-most vertices. +// +// A floor block only adjusts the top four vertices; the bottom four vertices +// remain at the bottom of the block. The height values are 2 bits, +// measured in halves of a block; so you can specify heights of 0/2, +// 1/2, 2/2, or 3/2. 0 is the bottom of the block, 1 is halfway +// up the block, 2 is the top of the block, and 3 is halfway up the +// next block (and actually outside of the block). The value 3 is +// actually legal for floor vheight (but not ceiling), and allows you to: +// +// (A) have smoother terrain by having slopes that cross blocks, +// e.g. (1,1,3,3) is a regular-seeming slope halfway between blocks +// (B) make slopes steeper than 45-degrees, e.g. (0,0,3,3) +// +// (Because only z coordinates have half-block precision, and x&y are +// limited to block corner precision, it's not possible to make these +// things "properly" out of blocks, e.g. a half-slope block on its side +// or a sloped block halfway between blocks that's made out of two blocks.) +// +// If you define STBVOX_CONFIG_OPTIMIZED_VHEIGHT, then the top face +// (or bottom face for a ceiling vheight block) will be drawn as a +// single quad even if the four vertex heights aren't planar, and a +// single normal will be used over the entire quad. If you +// don't define it, then if the top face is non-planar, it will be +// split into two triangles, each with their own normal/lighting. +// (Note that since all output from stb_voxel_render is quad meshes, +// triangles are actually rendered as degenerate quads.) In this case, +// the distinction betwen STBVOX_GEOM_floor_vheight_03 and +// STBVOX_GEOM_floor_vheight_12 comes into play; the former introduces +// an edge from the SW to NE corner (i.e. from <0,0,?> to <1,1,?>), +// while the latter introduces an edge from the NW to SE corner +// (i.e. from <0,1,?> to <1,0,?>.) For a "lazy mesh" look, use +// exclusively _03 or _12. For a "classic mesh" look, alternate +// _03 and _12 in a checkerboard pattern. For a "smoothest surface" +// look, choose the edge based on actual vertex heights. +// +// The four vertex heights can come from several places. The simplest +// encoding is to just use the 'vheight' parameter which stores four +// explicit vertex heights for every block. This allows total independence, +// but at the cost of the largest memory usage, 1 byte per 3D block. +// Encode this with STBVOX_MAKE_VHEIGHT(vh_sw, vh_se, vh_nw, vh_ne). +// These coordinates are absolute, not affected by block rotations. +// +// An alternative if you just want to encode some very specific block +// types, not all the possibilities--say you just want half-height slopes, +// so you want (0,0,1,1) and (1,1,2,2)--then you can use block_vheight +// to specify them. The geometry rotation will cause block_vheight values +// to be rotated (because it's as if you're just defining a type of +// block). This value is also encoded with STBVOX_MAKE_VHEIGHT. +// +// If you want to save memory and you're creating a "continuous ground" +// sort of effect, you can make each vertex of the lattice share the +// vheight value; that is, two adjacent blocks that share a vertex will +// always get the same vheight value for that vertex. Then you need to +// store two bits of vheight for every block, which you do by storing it +// as part another data structure. Store the south-west vertex's vheight +// with the block. You can either use the "geometry" mesh variable (it's +// a parameter to STBVOX_MAKE_GEOMETRY) or you can store it in the +// "lighting" mesh variable if you defined STBVOX_CONFIG_VHEIGHT_IN_LIGHTING, +// using STBVOX_MAKE_LIGHTING_EXT(lighting,vheight). +// +// Note that if you start with a 2D height map and generate vheight data from +// it, you don't necessarily store only one value per (x,y) coordinate, +// as the same value may need to be set up at multiple z heights. For +// example, if height(8,8) = 13.5, then you want the block at (8,8,13) +// to store STBVOX_VERTEX_HEIGHT_half, and this will be used by blocks +// at (7,7,13), (8,7,13), (7,8,13), and (8,8,13). However, if you're +// allowing steep slopes, it might be the case that you have a block +// at (7,7,12) which is supposed to stick up to 13.5; that means +// you also need to store STBVOX_VERTEX_HEIGHT_one_and_a_half at (8,8,12). + +enum +{ + STBVOX_TEXLERP_FACE_0, + STBVOX_TEXLERP_FACE_half, + STBVOX_TEXLERP_FACE_1, + STBVOX_TEXLERP_FACE_use_vert, +}; + +enum +{ + STBVOX_TEXLERP_BASE_0, // 0.0 + STBVOX_TEXLERP_BASE_2_7, // 2/7 + STBVOX_TEXLERP_BASE_5_7, // 4/7 + STBVOX_TEXLERP_BASE_1 // 1.0 +}; + +enum +{ + STBVOX_TEXLERP3_0_8, + STBVOX_TEXLERP3_1_8, + STBVOX_TEXLERP3_2_8, + STBVOX_TEXLERP3_3_8, + STBVOX_TEXLERP3_4_8, + STBVOX_TEXLERP3_5_8, + STBVOX_TEXLERP3_6_8, + STBVOX_TEXLERP3_7_8, +}; + +#define STBVOX_FACE_NONE 7 + +#define STBVOX_BLOCKTYPE_EMPTY 0 + +#ifdef STBVOX_BLOCKTYPE_SHORT +#define STBVOX_BLOCKTYPE_HOLE 65535 +#else +#define STBVOX_BLOCKTYPE_HOLE 255 +#endif + +#define STBVOX_MAKE_GEOMETRY(geom, rotate, vheight) ((geom) + (rotate)*16 + (vheight)*64) +#define STBVOX_MAKE_VHEIGHT(v_sw, v_se, v_nw, v_ne) ((v_sw) + (v_se)*4 + (v_nw)*16 + (v_ne)*64) +#define STBVOX_MAKE_MATROT(block, overlay, color) ((block) + (overlay)*4 + (color)*64) +#define STBVOX_MAKE_TEX2_REPLACE(tex2, tex2_replace_face) ((tex2) + ((tex2_replace_face) & 3)*64) +#define STBVOX_MAKE_TEXLERP(ns2, ew2, ud2, vert) ((ew2) + (ns2)*4 + (ud2)*16 + (vert)*64) +#define STBVOX_MAKE_TEXLERP_SIMPLE(baselerp,vert,face) ((vert)*32 + (face)*4 + (baselerp)) +#define STBVOX_MAKE_TEXLERP1(vert,e2,n2,w2,s2,u4,d2) STBVOX_MAKE_TEXLERP(s2, w2, d2, vert) +#define STBVOX_MAKE_TEXLERP2(vert,e2,n2,w2,s2,u4,d2) ((u2)*16 + (n2)*4 + (s2)) +#define STBVOX_MAKE_FACE_MASK(e,n,w,s,u,d) ((e)+(n)*2+(w)*4+(s)*8+(u)*16+(d)*32) +#define STBVOX_MAKE_SIDE_TEXROT(e,n,w,s) ((e)+(n)*4+(w)*16+(s)*64) +#define STBVOX_MAKE_COLOR(color,t1,t2) ((color)+(t1)*64+(t2)*128) +#define STBVOX_MAKE_TEXLERP_VERT3(e,n,w,s,u) ((e)+(n)*8+(w)*64+(s)*512+(u)*4096) +#define STBVOX_MAKE_TEXLERP_FACE3(e,n,w,s,u,d) ((e)+(n)*8+(w)*64+(s)*512+(u)*4096+(d)*16384) +#define STBVOX_MAKE_PACKED_COMPACT(rot, vheight, texlerp, def) ((rot)+4*(vheight)+16*(use)+32*(texlerp)) + +#define STBVOX_MAKE_LIGHTING_EXT(lighting, rot) (((lighting)&~3)+(rot)) +#define STBVOX_MAKE_LIGHTING(lighting) (lighting) + +#ifndef STBVOX_MAX_MESHES +#define STBVOX_MAX_MESHES 2 // opaque & transparent +#endif + +#define STBVOX_MAX_MESH_SLOTS 3 // one vertex & two faces, or two vertex and one face + + +// don't mess with this directly, it's just here so you can +// declare stbvox_mesh_maker on the stack or as a global +struct stbvox_mesh_maker +{ + stbvox_input_description input; + int cur_x, cur_y, cur_z; // last unprocessed voxel if it splits into multiple buffers + int x0,y0,z0,x1,y1,z1; + int x_stride_in_bytes; + int y_stride_in_bytes; + int config_dirty; + int default_mesh; + unsigned int tags; + + int cube_vertex_offset[6][4]; // this allows access per-vertex data stored block-centered (like texlerp, ambient) + int vertex_gather_offset[6][4]; + + int pos_x,pos_y,pos_z; + int full; + + // computed from user input + char *output_cur [STBVOX_MAX_MESHES][STBVOX_MAX_MESH_SLOTS]; + char *output_end [STBVOX_MAX_MESHES][STBVOX_MAX_MESH_SLOTS]; + char *output_buffer[STBVOX_MAX_MESHES][STBVOX_MAX_MESH_SLOTS]; + int output_len [STBVOX_MAX_MESHES][STBVOX_MAX_MESH_SLOTS]; + + // computed from config + int output_size [STBVOX_MAX_MESHES][STBVOX_MAX_MESH_SLOTS]; // per quad + int output_step [STBVOX_MAX_MESHES][STBVOX_MAX_MESH_SLOTS]; // per vertex or per face, depending + int num_mesh_slots; + + float default_tex_scale[128][2]; +}; + +#endif // INCLUDE_STB_VOXEL_RENDER_H + + +#ifdef STB_VOXEL_RENDER_IMPLEMENTATION + +#include <stdlib.h> +#include <assert.h> +#include <string.h> // memset + +// have to use our own names to avoid the _MSC_VER path having conflicting type names +#ifndef _MSC_VER + #include <stdint.h> + typedef uint16_t stbvox_uint16; + typedef uint32_t stbvox_uint32; +#else + typedef unsigned short stbvox_uint16; + typedef unsigned int stbvox_uint32; +#endif + +#ifdef _MSC_VER + #define STBVOX_NOTUSED(v) (void)(v) +#else + #define STBVOX_NOTUSED(v) (void)sizeof(v) +#endif + + + +#ifndef STBVOX_CONFIG_MODE +#error "Must defined STBVOX_CONFIG_MODE to select the mode" +#endif + +#if defined(STBVOX_CONFIG_ROTATION_IN_LIGHTING) && defined(STBVOX_CONFIG_VHEIGHT_IN_LIGHTING) +#error "Can't store both rotation and vheight in lighting" +#endif + + +// The following are candidate voxel modes. Only modes 0, 1, and 20, and 21 are +// currently implemented. Reducing the storage-per-quad further +// shouldn't improve performance, although obviously it allow you +// to create larger worlds without streaming. +// +// +// ----------- Two textures ----------- -- One texture -- ---- Color only ---- +// Mode: 0 1 2 3 4 5 6 10 11 12 20 21 22 23 24 +// ============================================================================================================ +// uses Tex Buffer n Y Y Y Y Y Y Y Y Y n Y Y Y Y +// bytes per quad 32 20 14 12 10 6 6 8 8 4 32 20 10 6 4 +// non-blocks all all some some some slabs stairs some some none all all slabs slabs none +// tex1 256 256 256 256 256 256 256 256 256 256 n n n n n +// tex2 256 256 256 256 256 256 128 n n n n n n n n +// colors 64 64 64 64 64 64 64 8 n n 2^24 2^24 2^24 2^24 256 +// vertex ao Y Y Y Y Y n n Y Y n Y Y Y n n +// vertex texlerp Y Y Y n n n n - - - - - - - - +// x&y extents 127 127 128 64 64 128 64 64 128 128 127 127 128 128 128 +// z extents 255 255 128 64? 64? 64 64 32 64 128 255 255 128 64 128 + +// not sure why I only wrote down the above "result data" and didn't preserve +// the vertex formats, but here I've tried to reconstruct the designs... +// mode # 3 is wrong, one byte too large, but they may have been an error originally + +// Mode: 0 1 2 3 4 5 6 10 11 12 20 21 22 23 24 +// ============================================================================================================= +// bytes per quad 32 20 14 12 10 6 6 8 8 4 20 10 6 4 +// +// vertex x bits 7 7 0 6 0 0 0 0 0 0 7 0 0 0 +// vertex y bits 7 7 0 0 0 0 0 0 0 0 7 0 0 0 +// vertex z bits 9 9 7 4 2 0 0 2 2 0 9 2 0 0 +// vertex ao bits 6 6 6 6 6 0 0 6 6 0 6 6 0 0 +// vertex txl bits 3 3 3 0 0 0 0 0 0 0 (3) 0 0 0 +// +// face tex1 bits (8) 8 8 8 8 8 8 8 8 8 +// face tex2 bits (8) 8 8 8 8 8 7 - - - +// face color bits (8) 8 8 8 8 8 8 3 0 0 24 24 24 8 +// face normal bits (8) 8 8 8 6 4 7 4 4 3 8 3 4 3 +// face x bits 7 0 6 7 6 6 7 7 0 7 7 7 +// face y bits 7 6 6 7 6 6 7 7 0 7 7 7 +// face z bits 2 2 6 6 6 5 6 7 0 7 6 7 + + +#if STBVOX_CONFIG_MODE==0 || STBVOX_CONFIG_MODE==1 + + #define STBVOX_ICONFIG_VERTEX_32 + #define STBVOX_ICONFIG_FACE1_1 + +#elif STBVOX_CONFIG_MODE==20 || STBVOX_CONFIG_MODE==21 + + #define STBVOX_ICONFIG_VERTEX_32 + #define STBVOX_ICONFIG_FACE1_1 + #define STBVOX_ICONFIG_UNTEXTURED + +#else +#error "Selected value of STBVOX_CONFIG_MODE is not supported" +#endif + +#if STBVOX_CONFIG_MODE==0 || STBVOX_CONFIG_MODE==20 +#define STBVOX_ICONFIG_FACE_ATTRIBUTE +#endif + +#ifndef STBVOX_CONFIG_HLSL +// the fallback if all others are exhausted is GLSL +#define STBVOX_ICONFIG_GLSL +#endif + +#ifdef STBVOX_CONFIG_OPENGL_MODELVIEW +#define STBVOX_ICONFIG_OPENGL_3_1_COMPATIBILITY +#endif + +#if defined(STBVOX_ICONFIG_VERTEX_32) + typedef stbvox_uint32 stbvox_mesh_vertex; + #define stbvox_vertex_encode(x,y,z,ao,texlerp) \ + ((stbvox_uint32) ((x)+((y)<<7)+((z)<<14)+((ao)<<23)+((texlerp)<<29))) +#elif defined(STBVOX_ICONFIG_VERTEX_16_1) // mode=2 + typedef stbvox_uint16 stbvox_mesh_vertex; + #define stbvox_vertex_encode(x,y,z,ao,texlerp) \ + ((stbvox_uint16) ((z)+((ao)<<7)+((texlerp)<<13) +#elif defined(STBVOX_ICONFIG_VERTEX_16_2) // mode=3 + typedef stbvox_uint16 stbvox_mesh_vertex; + #define stbvox_vertex_encode(x,y,z,ao,texlerp) \ + ((stbvox_uint16) ((x)+((z)<<6))+((ao)<<10)) +#elif defined(STBVOX_ICONFIG_VERTEX_8) + typedef stbvox_uint8 stbvox_mesh_vertex; + #define stbvox_vertex_encode(x,y,z,ao,texlerp) \ + ((stbvox_uint8) ((z)+((ao)<<6)) +#else + #error "internal error, no vertex type" +#endif + +#ifdef STBVOX_ICONFIG_FACE1_1 + typedef struct + { + unsigned char tex1,tex2,color,face_info; + } stbvox_mesh_face; +#else + #error "internal error, no face type" +#endif + + +// 20-byte quad format: +// +// per vertex: +// +// x:7 +// y:7 +// z:9 +// ao:6 +// tex_lerp:3 +// +// per face: +// +// tex1:8 +// tex2:8 +// face:8 +// color:8 + + +// Faces: +// +// Faces use the bottom 3 bits to choose the texgen +// mode, and all the bits to choose the normal. +// Thus the bottom 3 bits have to be: +// e, n, w, s, u, d, u, d +// +// These use compact names so tables are readable + +enum +{ + STBVF_e, + STBVF_n, + STBVF_w, + STBVF_s, + STBVF_u, + STBVF_d, + STBVF_eu, + STBVF_ed, + + STBVF_eu_wall, + STBVF_nu_wall, + STBVF_wu_wall, + STBVF_su_wall, + STBVF_ne_u, + STBVF_ne_d, + STBVF_nu, + STBVF_nd, + + STBVF_ed_wall, + STBVF_nd_wall, + STBVF_wd_wall, + STBVF_sd_wall, + STBVF_nw_u, + STBVF_nw_d, + STBVF_wu, + STBVF_wd, + + STBVF_ne_u_cross, + STBVF_nw_u_cross, + STBVF_sw_u_cross, + STBVF_se_u_cross, + STBVF_sw_u, + STBVF_sw_d, + STBVF_su, + STBVF_sd, + + // @TODO we need more than 5 bits to encode the normal to fit the following + // so for now we use the right projection but the wrong normal + STBVF_se_u = STBVF_su, + STBVF_se_d = STBVF_sd, + + STBVF_count, +}; + +///////////////////////////////////////////////////////////////////////////// +// +// tables -- i'd prefer if these were at the end of the file, but: C++ +// + +static float stbvox_default_texgen[2][32][3] = +{ + { { 0, 1,0 }, { 0, 0, 1 }, { 0,-1,0 }, { 0, 0,-1 }, + { -1, 0,0 }, { 0, 0, 1 }, { 1, 0,0 }, { 0, 0,-1 }, + { 0,-1,0 }, { 0, 0, 1 }, { 0, 1,0 }, { 0, 0,-1 }, + { 1, 0,0 }, { 0, 0, 1 }, { -1, 0,0 }, { 0, 0,-1 }, + + { 1, 0,0 }, { 0, 1, 0 }, { -1, 0,0 }, { 0,-1, 0 }, + { -1, 0,0 }, { 0,-1, 0 }, { 1, 0,0 }, { 0, 1, 0 }, + { 1, 0,0 }, { 0, 1, 0 }, { -1, 0,0 }, { 0,-1, 0 }, + { -1, 0,0 }, { 0,-1, 0 }, { 1, 0,0 }, { 0, 1, 0 }, + }, + { { 0, 0,-1 }, { 0, 1,0 }, { 0, 0, 1 }, { 0,-1,0 }, + { 0, 0,-1 }, { -1, 0,0 }, { 0, 0, 1 }, { 1, 0,0 }, + { 0, 0,-1 }, { 0,-1,0 }, { 0, 0, 1 }, { 0, 1,0 }, + { 0, 0,-1 }, { 1, 0,0 }, { 0, 0, 1 }, { -1, 0,0 }, + + { 0,-1, 0 }, { 1, 0,0 }, { 0, 1, 0 }, { -1, 0,0 }, + { 0, 1, 0 }, { -1, 0,0 }, { 0,-1, 0 }, { 1, 0,0 }, + { 0,-1, 0 }, { 1, 0,0 }, { 0, 1, 0 }, { -1, 0,0 }, + { 0, 1, 0 }, { -1, 0,0 }, { 0,-1, 0 }, { 1, 0,0 }, + }, +}; + +#define STBVOX_RSQRT2 0.7071067811865f +#define STBVOX_RSQRT3 0.5773502691896f + +static float stbvox_default_normals[32][3] = +{ + { 1,0,0 }, // east + { 0,1,0 }, // north + { -1,0,0 }, // west + { 0,-1,0 }, // south + { 0,0,1 }, // up + { 0,0,-1 }, // down + { STBVOX_RSQRT2,0, STBVOX_RSQRT2 }, // east & up + { STBVOX_RSQRT2,0, -STBVOX_RSQRT2 }, // east & down + + { STBVOX_RSQRT2,0, STBVOX_RSQRT2 }, // east & up + { 0, STBVOX_RSQRT2, STBVOX_RSQRT2 }, // north & up + { -STBVOX_RSQRT2,0, STBVOX_RSQRT2 }, // west & up + { 0,-STBVOX_RSQRT2, STBVOX_RSQRT2 }, // south & up + { STBVOX_RSQRT3, STBVOX_RSQRT3, STBVOX_RSQRT3 }, // ne & up + { STBVOX_RSQRT3, STBVOX_RSQRT3,-STBVOX_RSQRT3 }, // ne & down + { 0, STBVOX_RSQRT2, STBVOX_RSQRT2 }, // north & up + { 0, STBVOX_RSQRT2, -STBVOX_RSQRT2 }, // north & down + + { STBVOX_RSQRT2,0, -STBVOX_RSQRT2 }, // east & down + { 0, STBVOX_RSQRT2, -STBVOX_RSQRT2 }, // north & down + { -STBVOX_RSQRT2,0, -STBVOX_RSQRT2 }, // west & down + { 0,-STBVOX_RSQRT2, -STBVOX_RSQRT2 }, // south & down + { -STBVOX_RSQRT3, STBVOX_RSQRT3, STBVOX_RSQRT3 }, // NW & up + { -STBVOX_RSQRT3, STBVOX_RSQRT3,-STBVOX_RSQRT3 }, // NW & down + { -STBVOX_RSQRT2,0, STBVOX_RSQRT2 }, // west & up + { -STBVOX_RSQRT2,0, -STBVOX_RSQRT2 }, // west & down + + { STBVOX_RSQRT3, STBVOX_RSQRT3,STBVOX_RSQRT3 }, // NE & up crossed + { -STBVOX_RSQRT3, STBVOX_RSQRT3,STBVOX_RSQRT3 }, // NW & up crossed + { -STBVOX_RSQRT3,-STBVOX_RSQRT3,STBVOX_RSQRT3 }, // SW & up crossed + { STBVOX_RSQRT3,-STBVOX_RSQRT3,STBVOX_RSQRT3 }, // SE & up crossed + { -STBVOX_RSQRT3,-STBVOX_RSQRT3, STBVOX_RSQRT3 }, // SW & up + { -STBVOX_RSQRT3,-STBVOX_RSQRT3,-STBVOX_RSQRT3 }, // SW & up + { 0,-STBVOX_RSQRT2, STBVOX_RSQRT2 }, // south & up + { 0,-STBVOX_RSQRT2, -STBVOX_RSQRT2 }, // south & down +}; + +static float stbvox_default_texscale[128][4] = +{ + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, + {1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0},{1,1,0,0}, +}; + +static unsigned char stbvox_default_palette_compact[64][3] = +{ + { 255,255,255 }, { 238,238,238 }, { 221,221,221 }, { 204,204,204 }, + { 187,187,187 }, { 170,170,170 }, { 153,153,153 }, { 136,136,136 }, + { 119,119,119 }, { 102,102,102 }, { 85, 85, 85 }, { 68, 68, 68 }, + { 51, 51, 51 }, { 34, 34, 34 }, { 17, 17, 17 }, { 0, 0, 0 }, + { 255,240,240 }, { 255,220,220 }, { 255,160,160 }, { 255, 32, 32 }, + { 200,120,160 }, { 200, 60,150 }, { 220,100,130 }, { 255, 0,128 }, + { 240,240,255 }, { 220,220,255 }, { 160,160,255 }, { 32, 32,255 }, + { 120,160,200 }, { 60,150,200 }, { 100,130,220 }, { 0,128,255 }, + { 240,255,240 }, { 220,255,220 }, { 160,255,160 }, { 32,255, 32 }, + { 160,200,120 }, { 150,200, 60 }, { 130,220,100 }, { 128,255, 0 }, + { 255,255,240 }, { 255,255,220 }, { 220,220,180 }, { 255,255, 32 }, + { 200,160,120 }, { 200,150, 60 }, { 220,130,100 }, { 255,128, 0 }, + { 255,240,255 }, { 255,220,255 }, { 220,180,220 }, { 255, 32,255 }, + { 160,120,200 }, { 150, 60,200 }, { 130,100,220 }, { 128, 0,255 }, + { 240,255,255 }, { 220,255,255 }, { 180,220,220 }, { 32,255,255 }, + { 120,200,160 }, { 60,200,150 }, { 100,220,130 }, { 0,255,128 }, +}; + +static float stbvox_default_ambient[4][4] = +{ + { 0,0,1 ,0 }, // reversed lighting direction + { 0.5,0.5,0.5,0 }, // directional color + { 0.5,0.5,0.5,0 }, // constant color + { 0.5,0.5,0.5,1.0f/1000.0f/1000.0f }, // fog data for simple_fog +}; + +static float stbvox_default_palette[64][4]; + +static void stbvox_build_default_palette(void) +{ + int i; + for (i=0; i < 64; ++i) { + stbvox_default_palette[i][0] = stbvox_default_palette_compact[i][0] / 255.0f; + stbvox_default_palette[i][1] = stbvox_default_palette_compact[i][1] / 255.0f; + stbvox_default_palette[i][2] = stbvox_default_palette_compact[i][2] / 255.0f; + stbvox_default_palette[i][3] = 1.0f; + } +} + +////////////////////////////////////////////////////////////////////////////// +// +// Shaders +// + +#if defined(STBVOX_ICONFIG_OPENGL_3_1_COMPATIBILITY) + #define STBVOX_SHADER_VERSION "#version 150 compatibility\n" +#elif defined(STBVOX_ICONFIG_OPENGL_3_0) + #define STBVOX_SHADER_VERSION "#version 130\n" +#elif defined(STBVOX_ICONFIG_GLSL) + #define STBVOX_SHADER_VERSION "#version 150\n" +#else + #define STBVOX_SHADER_VERSION "" +#endif + +static const char *stbvox_vertex_program = +{ + STBVOX_SHADER_VERSION + + #ifdef STBVOX_ICONFIG_FACE_ATTRIBUTE // NOT TAG_face_sampled + "in uvec4 attr_face;\n" + #else + "uniform usamplerBuffer facearray;\n" + #endif + + #ifdef STBVOX_ICONFIG_FACE_ARRAY_2 + "uniform usamplerBuffer facearray2;\n" + #endif + + // vertex input data + "in uint attr_vertex;\n" + + // per-buffer data + "uniform vec3 transform[3];\n" + + // per-frame data + "uniform vec4 camera_pos;\n" // 4th value is used for arbitrary hacking + + // to simplify things, we avoid using more than 256 uniform vectors + // in fragment shader to avoid possible 1024 component limit, so + // we access this table in the fragment shader. + "uniform vec3 normal_table[32];\n" + + #ifndef STBVOX_CONFIG_OPENGL_MODELVIEW + "uniform mat4x4 model_view;\n" + #endif + + // fragment output data + "flat out uvec4 facedata;\n" + " out vec3 voxelspace_pos;\n" + " out vec3 vnormal;\n" + " out float texlerp;\n" + " out float amb_occ;\n" + + // @TODO handle the HLSL way to do this + "void main()\n" + "{\n" + #ifdef STBVOX_ICONFIG_FACE_ATTRIBUTE + " facedata = attr_face;\n" + #else + " int faceID = gl_VertexID >> 2;\n" + " facedata = texelFetch(facearray, faceID);\n" + #endif + + // extract data for vertex + " vec3 offset;\n" + " offset.x = float( (attr_vertex ) & 127u );\n" // a[0..6] + " offset.y = float( (attr_vertex >> 7u) & 127u );\n" // a[7..13] + " offset.z = float( (attr_vertex >> 14u) & 511u );\n" // a[14..22] + " amb_occ = float( (attr_vertex >> 23u) & 63u ) / 63.0;\n" // a[23..28] + " texlerp = float( (attr_vertex >> 29u) ) / 7.0;\n" // a[29..31] + + " vnormal = normal_table[(facedata.w>>2u) & 31u];\n" + " voxelspace_pos = offset * transform[0];\n" // mesh-to-object scale + " vec3 position = voxelspace_pos + transform[1];\n" // mesh-to-object translate + + #ifdef STBVOX_DEBUG_TEST_NORMALS + " if ((facedata.w & 28u) == 16u || (facedata.w & 28u) == 24u)\n" + " position += vnormal.xyz * camera_pos.w;\n" + #endif + + #ifndef STBVOX_CONFIG_OPENGL_MODELVIEW + " gl_Position = model_view * vec4(position,1.0);\n" + #else + " gl_Position = gl_ModelViewProjectionMatrix * vec4(position,1.0);\n" + #endif + + "}\n" +}; + + +static const char *stbvox_fragment_program = +{ + STBVOX_SHADER_VERSION + + // rlerp is lerp but with t on the left, like god intended + #if defined(STBVOX_ICONFIG_GLSL) + "#define rlerp(t,x,y) mix(x,y,t)\n" + #elif defined(STBVOX_CONFIG_HLSL) + "#define rlerp(t,x,y) lerp(x,y,t)\n" + #else + #error "need definition of rlerp()" + #endif + + + // vertex-shader output data + "flat in uvec4 facedata;\n" + " in vec3 voxelspace_pos;\n" + " in vec3 vnormal;\n" + " in float texlerp;\n" + " in float amb_occ;\n" + + // per-buffer data + "uniform vec3 transform[3];\n" + + // per-frame data + "uniform vec4 camera_pos;\n" // 4th value is used for arbitrary hacking + + // probably constant data + "uniform vec4 ambient[4];\n" + + #ifndef STBVOX_ICONFIG_UNTEXTURED + // generally constant data + "uniform sampler2DArray tex_array[2];\n" + + #ifdef STBVOX_CONFIG_PREFER_TEXBUFFER + "uniform samplerBuffer color_table;\n" + "uniform samplerBuffer texscale;\n" + "uniform samplerBuffer texgen;\n" + #else + "uniform vec4 color_table[64];\n" + "uniform vec4 texscale[64];\n" // instead of 128, to avoid running out of uniforms + "uniform vec3 texgen[64];\n" + #endif + #endif + + "out vec4 outcolor;\n" + + #if defined(STBVOX_CONFIG_LIGHTING) || defined(STBVOX_CONFIG_LIGHTING_SIMPLE) + "vec3 compute_lighting(vec3 pos, vec3 norm, vec3 albedo, vec3 ambient);\n" + #endif + #if defined(STBVOX_CONFIG_FOG) || defined(STBVOX_CONFIG_FOG_SMOOTHSTEP) + "vec3 compute_fog(vec3 color, vec3 relative_pos, float fragment_alpha);\n" + #endif + + "void main()\n" + "{\n" + " vec3 albedo;\n" + " float fragment_alpha;\n" + + #ifndef STBVOX_ICONFIG_UNTEXTURED + // unpack the values + " uint tex1_id = facedata.x;\n" + " uint tex2_id = facedata.y;\n" + " uint texprojid = facedata.w & 31u;\n" + " uint color_id = facedata.z;\n" + + #ifndef STBVOX_CONFIG_PREFER_TEXBUFFER + // load from uniforms / texture buffers + " vec3 texgen_s = texgen[texprojid];\n" + " vec3 texgen_t = texgen[texprojid+32u];\n" + " float tex1_scale = texscale[tex1_id & 63u].x;\n" + " vec4 color = color_table[color_id & 63u];\n" + #ifndef STBVOX_CONFIG_DISABLE_TEX2 + " vec4 tex2_props = texscale[tex2_id & 63u];\n" + #endif + #else + " vec3 texgen_s = texelFetch(texgen, int(texprojid)).xyz;\n" + " vec3 texgen_t = texelFetch(texgen, int(texprojid+32u)).xyz;\n" + " float tex1_scale = texelFetch(texscale, int(tex1_id & 127u)).x;\n" + " vec4 color = texelFetch(color_table, int(color_id & 63u));\n" + #ifndef STBVOX_CONFIG_DISABLE_TEX2 + " vec4 tex2_props = texelFetch(texscale, int(tex1_id & 127u));\n" + #endif + #endif + + #ifndef STBVOX_CONFIG_DISABLE_TEX2 + " float tex2_scale = tex2_props.y;\n" + " bool texblend_mode = tex2_props.z != 0.0;\n" + #endif + " vec2 texcoord;\n" + " vec3 texturespace_pos = voxelspace_pos + transform[2].xyz;\n" + " texcoord.s = dot(texturespace_pos, texgen_s);\n" + " texcoord.t = dot(texturespace_pos, texgen_t);\n" + + " vec2 texcoord_1 = tex1_scale * texcoord;\n" + #ifndef STBVOX_CONFIG_DISABLE_TEX2 + " vec2 texcoord_2 = tex2_scale * texcoord;\n" + #endif + + #ifdef STBVOX_CONFIG_TEX1_EDGE_CLAMP + " texcoord_1 = texcoord_1 - floor(texcoord_1);\n" + " vec4 tex1 = textureGrad(tex_array[0], vec3(texcoord_1, float(tex1_id)), dFdx(tex1_scale*texcoord), dFdy(tex1_scale*texcoord));\n" + #else + " vec4 tex1 = texture(tex_array[0], vec3(texcoord_1, float(tex1_id)));\n" + #endif + + #ifndef STBVOX_CONFIG_DISABLE_TEX2 + #ifdef STBVOX_CONFIG_TEX2_EDGE_CLAMP + " texcoord_2 = texcoord_2 - floor(texcoord_2);\n" + " vec4 tex2 = textureGrad(tex_array[0], vec3(texcoord_2, float(tex2_id)), dFdx(tex2_scale*texcoord), dFdy(tex2_scale*texcoord));\n" + #else + " vec4 tex2 = texture(tex_array[1], vec3(texcoord_2, float(tex2_id)));\n" + #endif + #endif + + " bool emissive = (color.a > 1.0);\n" + " color.a = min(color.a, 1.0);\n" + + // recolor textures + " if ((color_id & 64u) != 0u) tex1.rgba *= color.rgba;\n" + " fragment_alpha = tex1.a;\n" + #ifndef STBVOX_CONFIG_DISABLE_TEX2 + " if ((color_id & 128u) != 0u) tex2.rgba *= color.rgba;\n" + + #ifdef STBVOX_CONFIG_PREMULTIPLIED_ALPHA + " tex2.rgba *= texlerp;\n" + #else + " tex2.a *= texlerp;\n" + #endif + + " if (texblend_mode)\n" + " albedo = tex1.xyz * rlerp(tex2.a, vec3(1.0,1.0,1.0), 2.0*tex2.xyz);\n" + " else {\n" + #ifdef STBVOX_CONFIG_PREMULTIPLIED_ALPHA + " albedo = (1.0-tex2.a)*tex1.xyz + tex2.xyz;\n" + #else + " albedo = rlerp(tex2.a, tex1.xyz, tex2.xyz);\n" + #endif + " fragment_alpha = tex1.a*(1-tex2.a)+tex2.a;\n" + " }\n" + #else + " albedo = tex1.xyz;\n" + #endif + + #else // UNTEXTURED + " vec4 color;" + " color.xyz = vec3(facedata.xyz) / 255.0;\n" + " bool emissive = false;\n" + " albedo = color.xyz;\n" + " fragment_alpha = 1.0;\n" + #endif + + #ifdef STBVOX_ICONFIG_VARYING_VERTEX_NORMALS + // currently, there are no modes that trigger this path; idea is that there + // could be a couple of bits per vertex to perturb the normal to e.g. get curved look + " vec3 normal = normalize(vnormal);\n" + #else + " vec3 normal = vnormal;\n" + #endif + + " vec3 ambient_color = dot(normal, ambient[0].xyz) * ambient[1].xyz + ambient[2].xyz;\n" + + " ambient_color = clamp(ambient_color, 0.0, 1.0);" + " ambient_color *= amb_occ;\n" + + " vec3 lit_color;\n" + " if (!emissive)\n" + #if defined(STBVOX_ICONFIG_LIGHTING) || defined(STBVOX_CONFIG_LIGHTING_SIMPLE) + " lit_color = compute_lighting(voxelspace_pos + transform[1], normal, albedo, ambient_color);\n" + #else + " lit_color = albedo * ambient_color ;\n" + #endif + " else\n" + " lit_color = albedo;\n" + + #if defined(STBVOX_ICONFIG_FOG) || defined(STBVOX_CONFIG_FOG_SMOOTHSTEP) + " vec3 dist = voxelspace_pos + (transform[1] - camera_pos.xyz);\n" + " lit_color = compute_fog(lit_color, dist, fragment_alpha);\n" + #endif + + #ifdef STBVOX_CONFIG_UNPREMULTIPLY + " vec4 final_color = vec4(lit_color/fragment_alpha, fragment_alpha);\n" + #else + " vec4 final_color = vec4(lit_color, fragment_alpha);\n" + #endif + " outcolor = final_color;\n" + "}\n" + + #ifdef STBVOX_CONFIG_LIGHTING_SIMPLE + "\n" + "uniform vec3 light_source[2];\n" + "vec3 compute_lighting(vec3 pos, vec3 norm, vec3 albedo, vec3 ambient)\n" + "{\n" + " vec3 light_dir = light_source[0] - pos;\n" + " float lambert = dot(light_dir, norm) / dot(light_dir, light_dir);\n" + " vec3 diffuse = clamp(light_source[1] * clamp(lambert, 0.0, 1.0), 0.0, 1.0);\n" + " return (diffuse + ambient) * albedo;\n" + "}\n" + #endif + + #ifdef STBVOX_CONFIG_FOG_SMOOTHSTEP + "\n" + "vec3 compute_fog(vec3 color, vec3 relative_pos, float fragment_alpha)\n" + "{\n" + " float f = dot(relative_pos,relative_pos)*ambient[3].w;\n" + //" f = rlerp(f, -2,1);\n" + " f = clamp(f, 0.0, 1.0);\n" + " f = 3.0*f*f - 2.0*f*f*f;\n" // smoothstep + //" f = f*f;\n" // fade in more smoothly + #ifdef STBVOX_CONFIG_PREMULTIPLIED_ALPHA + " return rlerp(f, color.xyz, ambient[3].xyz*fragment_alpha);\n" + #else + " return rlerp(f, color.xyz, ambient[3].xyz);\n" + #endif + "}\n" + #endif +}; + + +// still requires full alpha lookups, including tex2 if texblend is enabled +static const char *stbvox_fragment_program_alpha_only = +{ + STBVOX_SHADER_VERSION + + // vertex-shader output data + "flat in uvec4 facedata;\n" + " in vec3 voxelspace_pos;\n" + " in float texlerp;\n" + + // per-buffer data + "uniform vec3 transform[3];\n" + + #ifndef STBVOX_ICONFIG_UNTEXTURED + // generally constant data + "uniform sampler2DArray tex_array[2];\n" + + #ifdef STBVOX_CONFIG_PREFER_TEXBUFFER + "uniform samplerBuffer texscale;\n" + "uniform samplerBuffer texgen;\n" + #else + "uniform vec4 texscale[64];\n" // instead of 128, to avoid running out of uniforms + "uniform vec3 texgen[64];\n" + #endif + #endif + + "out vec4 outcolor;\n" + + "void main()\n" + "{\n" + " vec3 albedo;\n" + " float fragment_alpha;\n" + + #ifndef STBVOX_ICONFIG_UNTEXTURED + // unpack the values + " uint tex1_id = facedata.x;\n" + " uint tex2_id = facedata.y;\n" + " uint texprojid = facedata.w & 31u;\n" + " uint color_id = facedata.z;\n" + + #ifndef STBVOX_CONFIG_PREFER_TEXBUFFER + // load from uniforms / texture buffers + " vec3 texgen_s = texgen[texprojid];\n" + " vec3 texgen_t = texgen[texprojid+32u];\n" + " float tex1_scale = texscale[tex1_id & 63u].x;\n" + " vec4 color = color_table[color_id & 63u];\n" + " vec4 tex2_props = texscale[tex2_id & 63u];\n" + #else + " vec3 texgen_s = texelFetch(texgen, int(texprojid)).xyz;\n" + " vec3 texgen_t = texelFetch(texgen, int(texprojid+32u)).xyz;\n" + " float tex1_scale = texelFetch(texscale, int(tex1_id & 127u)).x;\n" + " vec4 color = texelFetch(color_table, int(color_id & 63u));\n" + " vec4 tex2_props = texelFetch(texscale, int(tex2_id & 127u));\n" + #endif + + #ifndef STBVOX_CONFIG_DISABLE_TEX2 + " float tex2_scale = tex2_props.y;\n" + " bool texblend_mode = tex2_props.z &((facedata.w & 128u) != 0u);\n" + #endif + + " color.a = min(color.a, 1.0);\n" + + " vec2 texcoord;\n" + " vec3 texturespace_pos = voxelspace_pos + transform[2].xyz;\n" + " texcoord.s = dot(texturespace_pos, texgen_s);\n" + " texcoord.t = dot(texturespace_pos, texgen_t);\n" + + " vec2 texcoord_1 = tex1_scale * texcoord;\n" + " vec2 texcoord_2 = tex2_scale * texcoord;\n" + + #ifdef STBVOX_CONFIG_TEX1_EDGE_CLAMP + " texcoord_1 = texcoord_1 - floor(texcoord_1);\n" + " vec4 tex1 = textureGrad(tex_array[0], vec3(texcoord_1, float(tex1_id)), dFdx(tex1_scale*texcoord), dFdy(tex1_scale*texcoord));\n" + #else + " vec4 tex1 = texture(tex_array[0], vec3(texcoord_1, float(tex1_id)));\n" + #endif + + " if ((color_id & 64u) != 0u) tex1.a *= color.a;\n" + " fragment_alpha = tex1.a;\n" + + #ifndef STBVOX_CONFIG_DISABLE_TEX2 + " if (!texblend_mode) {\n" + #ifdef STBVOX_CONFIG_TEX2_EDGE_CLAMP + " texcoord_2 = texcoord_2 - floor(texcoord_2);\n" + " vec4 tex2 = textureGrad(tex_array[0], vec3(texcoord_2, float(tex2_id)), dFdx(tex2_scale*texcoord), dFdy(tex2_scale*texcoord));\n" + #else + " vec4 tex2 = texture(tex_array[1], vec3(texcoord_2, float(tex2_id)));\n" + #endif + + " tex2.a *= texlerp;\n" + " if ((color_id & 128u) != 0u) tex2.rgba *= color.a;\n" + " fragment_alpha = tex1.a*(1-tex2.a)+tex2.a;\n" + "}\n" + "\n" + #endif + + #else // UNTEXTURED + " fragment_alpha = 1.0;\n" + #endif + + " outcolor = vec4(0.0, 0.0, 0.0, fragment_alpha);\n" + "}\n" +}; + + +STBVXDEC char *stbvox_get_vertex_shader(void) +{ + return (char *) stbvox_vertex_program; +} + +STBVXDEC char *stbvox_get_fragment_shader(void) +{ + return (char *) stbvox_fragment_program; +} + +STBVXDEC char *stbvox_get_fragment_shader_alpha_only(void) +{ + return (char *) stbvox_fragment_program_alpha_only; +} + +static float stbvox_dummy_transform[3][3]; + +#ifdef STBVOX_CONFIG_PREFER_TEXBUFFER +#define STBVOX_TEXBUF 1 +#else +#define STBVOX_TEXBUF 0 +#endif + +static stbvox_uniform_info stbvox_uniforms[] = +{ + { STBVOX_UNIFORM_TYPE_sampler , 4, 1, (char*) "facearray" , 0 }, + { STBVOX_UNIFORM_TYPE_vec3 , 12, 3, (char*) "transform" , stbvox_dummy_transform[0] }, + { STBVOX_UNIFORM_TYPE_sampler , 4, 2, (char*) "tex_array" , 0 }, + { STBVOX_UNIFORM_TYPE_vec4 , 16, 128, (char*) "texscale" , stbvox_default_texscale[0] , STBVOX_TEXBUF }, + { STBVOX_UNIFORM_TYPE_vec4 , 16, 64, (char*) "color_table" , stbvox_default_palette[0] , STBVOX_TEXBUF }, + { STBVOX_UNIFORM_TYPE_vec3 , 12, 32, (char*) "normal_table" , stbvox_default_normals[0] }, + { STBVOX_UNIFORM_TYPE_vec3 , 12, 64, (char*) "texgen" , stbvox_default_texgen[0][0], STBVOX_TEXBUF }, + { STBVOX_UNIFORM_TYPE_vec4 , 16, 4, (char*) "ambient" , stbvox_default_ambient[0] }, + { STBVOX_UNIFORM_TYPE_vec4 , 16, 1, (char*) "camera_pos" , stbvox_dummy_transform[0] }, +}; + +STBVXDEC int stbvox_get_uniform_info(stbvox_uniform_info *info, int uniform) +{ + if (uniform < 0 || uniform >= STBVOX_UNIFORM_count) + return 0; + + *info = stbvox_uniforms[uniform]; + return 1; +} + +#define STBVOX_GET_GEO(geom_data) ((geom_data) & 15) + +typedef struct +{ + unsigned char block:2; + unsigned char overlay:2; + unsigned char facerot:2; + unsigned char ecolor:2; +} stbvox_rotate; + +typedef struct +{ + unsigned char x,y,z; +} stbvox_pos; + +static unsigned char stbvox_rotate_face[6][4] = +{ + { 0,1,2,3 }, + { 1,2,3,0 }, + { 2,3,0,1 }, + { 3,0,1,2 }, + { 4,4,4,4 }, + { 5,5,5,5 }, +}; + +#define STBVOX_ROTATE(x,r) stbvox_rotate_face[x][r] // (((x)+(r))&3) + +stbvox_mesh_face stbvox_compute_mesh_face_value(stbvox_mesh_maker *mm, stbvox_rotate rot, int face, int v_off, int normal) +{ + stbvox_mesh_face face_data = { 0 }; + stbvox_block_type bt = mm->input.blocktype[v_off]; + unsigned char bt_face = STBVOX_ROTATE(face, rot.block); + int facerot = rot.facerot; + + #ifdef STBVOX_ICONFIG_UNTEXTURED + if (mm->input.rgb) { + face_data.tex1 = mm->input.rgb[v_off].r; + face_data.tex2 = mm->input.rgb[v_off].g; + face_data.color = mm->input.rgb[v_off].b; + face_data.face_info = (normal<<2); + return face_data; + } + #else + unsigned char color_face; + + if (mm->input.color) + face_data.color = mm->input.color[v_off]; + + if (mm->input.block_tex1) + face_data.tex1 = mm->input.block_tex1[bt]; + else if (mm->input.block_tex1_face) + face_data.tex1 = mm->input.block_tex1_face[bt][bt_face]; + else + face_data.tex1 = bt; + + if (mm->input.block_tex2) + face_data.tex2 = mm->input.block_tex2[bt]; + else if (mm->input.block_tex2_face) + face_data.tex2 = mm->input.block_tex2_face[bt][bt_face]; + + if (mm->input.block_color) { + unsigned char mcol = mm->input.block_color[bt]; + if (mcol) + face_data.color = mcol; + } else if (mm->input.block_color_face) { + unsigned char mcol = mm->input.block_color_face[bt][bt_face]; + if (mcol) + face_data.color = mcol; + } + + if (face <= STBVOX_FACE_south) { + if (mm->input.side_texrot) + facerot = mm->input.side_texrot[v_off] >> (2 * face); + else if (mm->input.block_side_texrot) + facerot = mm->input.block_side_texrot[v_off] >> (2 * bt_face); + } + + if (mm->input.overlay) { + int over_face = STBVOX_ROTATE(face, rot.overlay); + unsigned char over = mm->input.overlay[v_off]; + if (over) { + if (mm->input.overlay_tex1) { + unsigned char rep1 = mm->input.overlay_tex1[over][over_face]; + if (rep1) + face_data.tex1 = rep1; + } + if (mm->input.overlay_tex2) { + unsigned char rep2 = mm->input.overlay_tex2[over][over_face]; + if (rep2) + face_data.tex2 = rep2; + } + if (mm->input.overlay_color) { + unsigned char rep3 = mm->input.overlay_color[over][over_face]; + if (rep3) + face_data.color = rep3; + } + + if (mm->input.overlay_side_texrot && face <= STBVOX_FACE_south) + facerot = mm->input.overlay_side_texrot[over] >> (2*over_face); + } + } + + if (mm->input.tex2_for_tex1) + face_data.tex2 = mm->input.tex2_for_tex1[face_data.tex1]; + if (mm->input.tex2) + face_data.tex2 = mm->input.tex2[v_off]; + if (mm->input.tex2_replace) { + if (mm->input.tex2_facemask[v_off] & (1 << face)) + face_data.tex2 = mm->input.tex2_replace[v_off]; + } + + color_face = STBVOX_ROTATE(face, rot.ecolor); + if (mm->input.extended_color) { + unsigned char ec = mm->input.extended_color[v_off]; + if (mm->input.ecolor_facemask[ec] & (1 << color_face)) + face_data.color = mm->input.ecolor_color[ec]; + } + + if (mm->input.color2) { + if (mm->input.color2_facemask[v_off] & (1 << color_face)) + face_data.color = mm->input.color2[v_off]; + if (mm->input.color3 && (mm->input.color3_facemask[v_off] & (1 << color_face))) + face_data.color = mm->input.color3[v_off]; + } + #endif + + face_data.face_info = (normal<<2) + facerot; + return face_data; +} + +// these are the types of faces each block can have +enum +{ + STBVOX_FT_none , + STBVOX_FT_upper , + STBVOX_FT_lower , + STBVOX_FT_solid , + STBVOX_FT_diag_012, + STBVOX_FT_diag_023, + STBVOX_FT_diag_013, + STBVOX_FT_diag_123, + STBVOX_FT_force , // can't be covered up, used for internal faces, also hides nothing + STBVOX_FT_partial , // only covered by solid, never covers anything else + + STBVOX_FT_count +}; + +static unsigned char stbvox_face_lerp[6] = { 0,2,0,2,4,4 }; +static unsigned char stbvox_vert3_lerp[5] = { 0,3,6,9,12 }; +static unsigned char stbvox_vert_lerp_for_face_lerp[4] = { 0, 4, 7, 7 }; +static unsigned char stbvox_face3_lerp[6] = { 0,3,6,9,12,14 }; +static unsigned char stbvox_vert_lerp_for_simple[4] = { 0,2,5,7 }; +static unsigned char stbvox_face3_updown[8] = { 0,2,5,7,0,2,5,7 }; // ignore top bit + +// vertex offsets for face vertices +static unsigned char stbvox_vertex_vector[6][4][3] = +{ + { { 1,0,1 }, { 1,1,1 }, { 1,1,0 }, { 1,0,0 } }, // east + { { 1,1,1 }, { 0,1,1 }, { 0,1,0 }, { 1,1,0 } }, // north + { { 0,1,1 }, { 0,0,1 }, { 0,0,0 }, { 0,1,0 } }, // west + { { 0,0,1 }, { 1,0,1 }, { 1,0,0 }, { 0,0,0 } }, // south + { { 0,1,1 }, { 1,1,1 }, { 1,0,1 }, { 0,0,1 } }, // up + { { 0,0,0 }, { 1,0,0 }, { 1,1,0 }, { 0,1,0 } }, // down +}; + +// stbvox_vertex_vector, but read coordinates as binary numbers, zyx +static unsigned char stbvox_vertex_selector[6][4] = +{ + { 5,7,3,1 }, + { 7,6,2,3 }, + { 6,4,0,2 }, + { 4,5,1,0 }, + { 6,7,5,4 }, + { 0,1,3,2 }, +}; + +static stbvox_mesh_vertex stbvox_vmesh_delta_normal[6][4] = +{ + { stbvox_vertex_encode(1,0,1,0,0) , + stbvox_vertex_encode(1,1,1,0,0) , + stbvox_vertex_encode(1,1,0,0,0) , + stbvox_vertex_encode(1,0,0,0,0) }, + { stbvox_vertex_encode(1,1,1,0,0) , + stbvox_vertex_encode(0,1,1,0,0) , + stbvox_vertex_encode(0,1,0,0,0) , + stbvox_vertex_encode(1,1,0,0,0) }, + { stbvox_vertex_encode(0,1,1,0,0) , + stbvox_vertex_encode(0,0,1,0,0) , + stbvox_vertex_encode(0,0,0,0,0) , + stbvox_vertex_encode(0,1,0,0,0) }, + { stbvox_vertex_encode(0,0,1,0,0) , + stbvox_vertex_encode(1,0,1,0,0) , + stbvox_vertex_encode(1,0,0,0,0) , + stbvox_vertex_encode(0,0,0,0,0) }, + { stbvox_vertex_encode(0,1,1,0,0) , + stbvox_vertex_encode(1,1,1,0,0) , + stbvox_vertex_encode(1,0,1,0,0) , + stbvox_vertex_encode(0,0,1,0,0) }, + { stbvox_vertex_encode(0,0,0,0,0) , + stbvox_vertex_encode(1,0,0,0,0) , + stbvox_vertex_encode(1,1,0,0,0) , + stbvox_vertex_encode(0,1,0,0,0) } +}; + +static stbvox_mesh_vertex stbvox_vmesh_pre_vheight[6][4] = +{ + { stbvox_vertex_encode(1,0,0,0,0) , + stbvox_vertex_encode(1,1,0,0,0) , + stbvox_vertex_encode(1,1,0,0,0) , + stbvox_vertex_encode(1,0,0,0,0) }, + { stbvox_vertex_encode(1,1,0,0,0) , + stbvox_vertex_encode(0,1,0,0,0) , + stbvox_vertex_encode(0,1,0,0,0) , + stbvox_vertex_encode(1,1,0,0,0) }, + { stbvox_vertex_encode(0,1,0,0,0) , + stbvox_vertex_encode(0,0,0,0,0) , + stbvox_vertex_encode(0,0,0,0,0) , + stbvox_vertex_encode(0,1,0,0,0) }, + { stbvox_vertex_encode(0,0,0,0,0) , + stbvox_vertex_encode(1,0,0,0,0) , + stbvox_vertex_encode(1,0,0,0,0) , + stbvox_vertex_encode(0,0,0,0,0) }, + { stbvox_vertex_encode(0,1,0,0,0) , + stbvox_vertex_encode(1,1,0,0,0) , + stbvox_vertex_encode(1,0,0,0,0) , + stbvox_vertex_encode(0,0,0,0,0) }, + { stbvox_vertex_encode(0,0,0,0,0) , + stbvox_vertex_encode(1,0,0,0,0) , + stbvox_vertex_encode(1,1,0,0,0) , + stbvox_vertex_encode(0,1,0,0,0) } +}; + +static stbvox_mesh_vertex stbvox_vmesh_delta_half_z[6][4] = +{ + { stbvox_vertex_encode(1,0,2,0,0) , + stbvox_vertex_encode(1,1,2,0,0) , + stbvox_vertex_encode(1,1,0,0,0) , + stbvox_vertex_encode(1,0,0,0,0) }, + { stbvox_vertex_encode(1,1,2,0,0) , + stbvox_vertex_encode(0,1,2,0,0) , + stbvox_vertex_encode(0,1,0,0,0) , + stbvox_vertex_encode(1,1,0,0,0) }, + { stbvox_vertex_encode(0,1,2,0,0) , + stbvox_vertex_encode(0,0,2,0,0) , + stbvox_vertex_encode(0,0,0,0,0) , + stbvox_vertex_encode(0,1,0,0,0) }, + { stbvox_vertex_encode(0,0,2,0,0) , + stbvox_vertex_encode(1,0,2,0,0) , + stbvox_vertex_encode(1,0,0,0,0) , + stbvox_vertex_encode(0,0,0,0,0) }, + { stbvox_vertex_encode(0,1,2,0,0) , + stbvox_vertex_encode(1,1,2,0,0) , + stbvox_vertex_encode(1,0,2,0,0) , + stbvox_vertex_encode(0,0,2,0,0) }, + { stbvox_vertex_encode(0,0,0,0,0) , + stbvox_vertex_encode(1,0,0,0,0) , + stbvox_vertex_encode(1,1,0,0,0) , + stbvox_vertex_encode(0,1,0,0,0) } +}; + +static stbvox_mesh_vertex stbvox_vmesh_crossed_pair[6][4] = +{ + { stbvox_vertex_encode(1,0,2,0,0) , + stbvox_vertex_encode(0,1,2,0,0) , + stbvox_vertex_encode(0,1,0,0,0) , + stbvox_vertex_encode(1,0,0,0,0) }, + { stbvox_vertex_encode(1,1,2,0,0) , + stbvox_vertex_encode(0,0,2,0,0) , + stbvox_vertex_encode(0,0,0,0,0) , + stbvox_vertex_encode(1,1,0,0,0) }, + { stbvox_vertex_encode(0,1,2,0,0) , + stbvox_vertex_encode(1,0,2,0,0) , + stbvox_vertex_encode(1,0,0,0,0) , + stbvox_vertex_encode(0,1,0,0,0) }, + { stbvox_vertex_encode(0,0,2,0,0) , + stbvox_vertex_encode(1,1,2,0,0) , + stbvox_vertex_encode(1,1,0,0,0) , + stbvox_vertex_encode(0,0,0,0,0) }, + // not used, so we leave it non-degenerate to make sure it doesn't get gen'd accidentally + { stbvox_vertex_encode(0,1,2,0,0) , + stbvox_vertex_encode(1,1,2,0,0) , + stbvox_vertex_encode(1,0,2,0,0) , + stbvox_vertex_encode(0,0,2,0,0) }, + { stbvox_vertex_encode(0,0,0,0,0) , + stbvox_vertex_encode(1,0,0,0,0) , + stbvox_vertex_encode(1,1,0,0,0) , + stbvox_vertex_encode(0,1,0,0,0) } +}; + +#define STBVOX_MAX_GEOM 16 +#define STBVOX_NUM_ROTATION 4 + +// this is used to determine if a face is ever generated at all +static unsigned char stbvox_hasface[STBVOX_MAX_GEOM][STBVOX_NUM_ROTATION] = +{ + { 0,0,0,0 }, // empty + { 0,0,0,0 }, // knockout + { 63,63,63,63 }, // solid + { 63,63,63,63 }, // transp + { 63,63,63,63 }, // slab + { 63,63,63,63 }, // slab + { 1|2|4|48, 8|1|2|48, 4|8|1|48, 2|4|8|48, }, // floor slopes + { 1|2|4|48, 8|1|2|48, 4|8|1|48, 2|4|8|48, }, // ceil slopes + { 47,47,47,47 }, // wall-projected diagonal with down face + { 31,31,31,31 }, // wall-projected diagonal with up face + { 63,63,63,63 }, // crossed-pair has special handling, but avoid early-out + { 63,63,63,63 }, // force + { 63,63,63,63 }, // vheight + { 63,63,63,63 }, // vheight + { 63,63,63,63 }, // vheight + { 63,63,63,63 }, // vheight +}; + +// this determines which face type above is visible on each side of the geometry +static unsigned char stbvox_facetype[STBVOX_GEOM_count][6] = +{ + { 0, }, // STBVOX_GEOM_empty + { STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid }, // knockout + { STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid, STBVOX_FT_solid }, // solid + { STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force }, // transp + + { STBVOX_FT_upper, STBVOX_FT_upper, STBVOX_FT_upper, STBVOX_FT_upper, STBVOX_FT_solid, STBVOX_FT_force }, + { STBVOX_FT_lower, STBVOX_FT_lower, STBVOX_FT_lower, STBVOX_FT_lower, STBVOX_FT_force, STBVOX_FT_solid }, + { STBVOX_FT_diag_123, STBVOX_FT_solid, STBVOX_FT_diag_023, STBVOX_FT_none, STBVOX_FT_force, STBVOX_FT_solid }, + { STBVOX_FT_diag_012, STBVOX_FT_solid, STBVOX_FT_diag_013, STBVOX_FT_none, STBVOX_FT_solid, STBVOX_FT_force }, + + { STBVOX_FT_diag_123, STBVOX_FT_solid, STBVOX_FT_diag_023, STBVOX_FT_force, STBVOX_FT_none, STBVOX_FT_solid }, + { STBVOX_FT_diag_012, STBVOX_FT_solid, STBVOX_FT_diag_013, STBVOX_FT_force, STBVOX_FT_solid, STBVOX_FT_none }, + { STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, 0,0 }, // crossed pair + { STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force, STBVOX_FT_force }, // GEOM_force + + { STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial, STBVOX_FT_force, STBVOX_FT_solid }, // floor vheight, all neighbors forced + { STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial, STBVOX_FT_force, STBVOX_FT_solid }, // floor vheight, all neighbors forced + { STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial, STBVOX_FT_solid, STBVOX_FT_force }, // ceil vheight, all neighbors forced + { STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial,STBVOX_FT_partial, STBVOX_FT_solid, STBVOX_FT_force }, // ceil vheight, all neighbors forced +}; + +// This table indicates what normal to use for the "up" face of a sloped geom +// @TODO this could be done with math given the current arrangement of the enum, but let's not require it +static unsigned char stbvox_floor_slope_for_rot[4] = +{ + STBVF_su, + STBVF_wu, // @TODO: why is this reversed from what it should be? this is a north-is-up face, so slope should be south&up + STBVF_nu, + STBVF_eu, +}; + +static unsigned char stbvox_ceil_slope_for_rot[4] = +{ + STBVF_sd, + STBVF_ed, + STBVF_nd, + STBVF_wd, +}; + +// this table indicates whether, for each pair of types above, a face is visible. +// each value indicates whether a given type is visible for all neighbor types +static unsigned short stbvox_face_visible[STBVOX_FT_count] = +{ + // we encode the table by listing which cases cause *obscuration*, and bitwise inverting that + // table is pre-shifted by 5 to save a shift when it's accessed + (unsigned short) ((~0x07ff )<<5), // none is completely obscured by everything + (unsigned short) ((~((1<<STBVOX_FT_solid) | (1<<STBVOX_FT_upper) ))<<5), // upper + (unsigned short) ((~((1<<STBVOX_FT_solid) | (1<<STBVOX_FT_lower) ))<<5), // lower + (unsigned short) ((~((1<<STBVOX_FT_solid) ))<<5), // solid is only completely obscured only by solid + (unsigned short) ((~((1<<STBVOX_FT_solid) | (1<<STBVOX_FT_diag_013)))<<5), // diag012 matches diag013 + (unsigned short) ((~((1<<STBVOX_FT_solid) | (1<<STBVOX_FT_diag_123)))<<5), // diag023 matches diag123 + (unsigned short) ((~((1<<STBVOX_FT_solid) | (1<<STBVOX_FT_diag_012)))<<5), // diag013 matches diag012 + (unsigned short) ((~((1<<STBVOX_FT_solid) | (1<<STBVOX_FT_diag_023)))<<5), // diag123 matches diag023 + (unsigned short) ((~0 )<<5), // force is always rendered regardless, always forces neighbor + (unsigned short) ((~((1<<STBVOX_FT_solid) ))<<5), // partial is only completely obscured only by solid +}; + +// the vertex heights of the block types, in binary vertex order (zyx): +// lower: SW, SE, NW, NE; upper: SW, SE, NW, NE +static stbvox_mesh_vertex stbvox_geometry_vheight[8][8] = +{ + #define STBVOX_HEIGHTS(a,b,c,d,e,f,g,h) \ + { stbvox_vertex_encode(0,0,a,0,0), \ + stbvox_vertex_encode(0,0,b,0,0), \ + stbvox_vertex_encode(0,0,c,0,0), \ + stbvox_vertex_encode(0,0,d,0,0), \ + stbvox_vertex_encode(0,0,e,0,0), \ + stbvox_vertex_encode(0,0,f,0,0), \ + stbvox_vertex_encode(0,0,g,0,0), \ + stbvox_vertex_encode(0,0,h,0,0) } + + STBVOX_HEIGHTS(0,0,0,0, 2,2,2,2), + STBVOX_HEIGHTS(0,0,0,0, 2,2,2,2), + STBVOX_HEIGHTS(0,0,0,0, 2,2,2,2), + STBVOX_HEIGHTS(0,0,0,0, 2,2,2,2), + STBVOX_HEIGHTS(1,1,1,1, 2,2,2,2), + STBVOX_HEIGHTS(0,0,0,0, 1,1,1,1), + STBVOX_HEIGHTS(0,0,0,0, 0,0,2,2), + STBVOX_HEIGHTS(2,2,0,0, 2,2,2,2), +}; + +// rotate vertices defined as [z][y][x] coords +static unsigned char stbvox_rotate_vertex[8][4] = +{ + { 0,1,3,2 }, // zyx=000 + { 1,3,2,0 }, // zyx=001 + { 2,0,1,3 }, // zyx=010 + { 3,2,0,1 }, // zyx=011 + { 4,5,7,6 }, // zyx=100 + { 5,7,6,4 }, // zyx=101 + { 6,4,5,7 }, // zyx=110 + { 7,6,4,5 }, // zyx=111 +}; + +#ifdef STBVOX_CONFIG_OPTIMIZED_VHEIGHT +// optimized vheight generates a single normal over the entire face, even if it's not planar +static unsigned char stbvox_optimized_face_up_normal[4][4][4][4] = +{ + { + { + { STBVF_u , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, }, + { STBVF_nw_u, STBVF_nu , STBVF_nu , STBVF_ne_u, }, + { STBVF_nw_u, STBVF_nu , STBVF_nu , STBVF_nu , }, + { STBVF_nw_u, STBVF_nw_u, STBVF_nu , STBVF_nu , }, + },{ + { STBVF_su , STBVF_eu , STBVF_eu , STBVF_ne_u, }, + { STBVF_u , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, }, + { STBVF_nw_u, STBVF_nu , STBVF_nu , STBVF_ne_u, }, + { STBVF_nw_u, STBVF_nu , STBVF_nu , STBVF_nu , }, + },{ + { STBVF_eu , STBVF_eu , STBVF_eu , STBVF_eu , }, + { STBVF_su , STBVF_eu , STBVF_eu , STBVF_ne_u, }, + { STBVF_u , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, }, + { STBVF_nw_u, STBVF_nu , STBVF_nu , STBVF_ne_u, }, + },{ + { STBVF_eu , STBVF_eu , STBVF_eu , STBVF_eu , }, + { STBVF_eu , STBVF_eu , STBVF_eu , STBVF_eu , }, + { STBVF_su , STBVF_eu , STBVF_eu , STBVF_ne_u, }, + { STBVF_u , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, }, + }, + },{ + { + { STBVF_sw_u, STBVF_u , STBVF_ne_u, STBVF_ne_u, }, + { STBVF_wu , STBVF_nw_u, STBVF_nu , STBVF_nu , }, + { STBVF_wu , STBVF_nw_u, STBVF_nu , STBVF_nu , }, + { STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, STBVF_nu , }, + },{ + { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , }, + { STBVF_sw_u, STBVF_u , STBVF_ne_u, STBVF_ne_u, }, + { STBVF_wu , STBVF_nw_u, STBVF_nu , STBVF_nu , }, + { STBVF_wu , STBVF_nw_u, STBVF_nu , STBVF_nu , }, + },{ + { STBVF_su , STBVF_eu , STBVF_eu , STBVF_eu , }, + { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , }, + { STBVF_sw_u, STBVF_u , STBVF_ne_u, STBVF_ne_u, }, + { STBVF_wu , STBVF_nw_u, STBVF_nu , STBVF_nu , }, + },{ + { STBVF_su , STBVF_eu , STBVF_eu , STBVF_eu , }, + { STBVF_su , STBVF_eu , STBVF_eu , STBVF_eu , }, + { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , }, + { STBVF_sw_u, STBVF_u , STBVF_ne_u, STBVF_ne_u, }, + }, + },{ + { + { STBVF_sw_u, STBVF_sw_u, STBVF_u , STBVF_ne_u, }, + { STBVF_wu , STBVF_wu , STBVF_nw_u, STBVF_nu , }, + { STBVF_wu , STBVF_wu , STBVF_nw_u, STBVF_nu , }, + { STBVF_wu , STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, }, + },{ + { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , }, + { STBVF_sw_u, STBVF_sw_u, STBVF_u , STBVF_ne_u, }, + { STBVF_wu , STBVF_wu , STBVF_nw_u, STBVF_nu , }, + { STBVF_wu , STBVF_wu , STBVF_nw_u, STBVF_nu , }, + },{ + { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , }, + { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , }, + { STBVF_sw_u, STBVF_sw_u, STBVF_u , STBVF_ne_u, }, + { STBVF_wu , STBVF_wu , STBVF_nw_u, STBVF_nu , }, + },{ + { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , }, + { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , }, + { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , }, + { STBVF_sw_u, STBVF_sw_u, STBVF_u , STBVF_ne_u, }, + }, + },{ + { + { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_u , }, + { STBVF_sw_u, STBVF_wu , STBVF_wu , STBVF_nw_u, }, + { STBVF_wu , STBVF_wu , STBVF_wu , STBVF_nw_u, }, + { STBVF_wu , STBVF_wu , STBVF_nw_u, STBVF_nw_u, }, + },{ + { STBVF_sw_u, STBVF_su , STBVF_su , STBVF_su , }, + { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_u , }, + { STBVF_sw_u, STBVF_wu , STBVF_wu , STBVF_nw_u, }, + { STBVF_wu , STBVF_wu , STBVF_wu , STBVF_nw_u, }, + },{ + { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , }, + { STBVF_sw_u, STBVF_su , STBVF_su , STBVF_su , }, + { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_u , }, + { STBVF_sw_u, STBVF_wu , STBVF_wu , STBVF_nw_u, }, + },{ + { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , }, + { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , }, + { STBVF_sw_u, STBVF_su , STBVF_su , STBVF_su , }, + { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_u , }, + }, + }, +}; +#else +// which normal to use for a given vheight that's planar +// @TODO: this table was constructed by hand and may have bugs +// nw se sw +static unsigned char stbvox_planar_face_up_normal[4][4][4] = +{ + { // sw,se,nw,ne; ne = se+nw-sw + { STBVF_u , 0 , 0 , 0 }, // 0,0,0,0; 1,0,0,-1; 2,0,0,-2; 3,0,0,-3; + { STBVF_u , STBVF_u , 0 , 0 }, // 0,1,0,1; 1,1,0, 0; 2,1,0,-1; 3,1,0,-2; + { STBVF_wu , STBVF_nw_u, STBVF_nu , 0 }, // 0,2,0,2; 1,2,0, 1; 2,2,0, 0; 3,2,0,-1; + { STBVF_wu , STBVF_nw_u, STBVF_nw_u, STBVF_nu }, // 0,3,0,3; 1,3,0, 2; 2,3,0, 1; 3,3,0, 0; + },{ + { STBVF_u , STBVF_u , 0 , 0 }, // 0,0,1,1; 1,0,1, 0; 2,0,1,-1; 3,0,1,-2; + { STBVF_sw_u, STBVF_u , STBVF_ne_u, 0 }, // 0,1,1,2; 1,1,1, 1; 2,1,1, 0; 3,1,1,-1; + { STBVF_sw_u, STBVF_u , STBVF_u , STBVF_ne_u }, // 0,2,1,3; 1,2,1, 2; 2,2,1, 1; 3,2,1, 0; + { 0 , STBVF_wu , STBVF_nw_u, STBVF_nu }, // 0,3,1,4; 1,3,1, 3; 2,3,1, 2; 3,3,1, 1; + },{ + { STBVF_su , STBVF_se_u, STBVF_eu , 0 }, // 0,0,2,2; 1,0,2, 1; 2,0,2, 0; 3,0,2,-1; + { STBVF_sw_u, STBVF_u , STBVF_u , STBVF_ne_u }, // 0,1,2,3; 1,1,2, 2; 2,1,2, 1; 3,1,2, 0; + { 0 , STBVF_sw_u, STBVF_u , STBVF_ne_u }, // 0,2,2,4; 1,2,2, 3; 2,2,2, 2; 3,2,2, 1; + { 0 , 0 , STBVF_u , STBVF_u }, // 0,3,2,5; 1,3,2, 4; 2,3,2, 3; 3,3,2, 2; + },{ + { STBVF_su , STBVF_se_u, STBVF_se_u, STBVF_eu }, // 0,0,3,3; 1,0,3, 2; 2,0,3, 1; 3,0,3, 0; + { 0 , STBVF_su , STBVF_se_u, STBVF_eu }, // 0,1,3,4; 1,1,3, 3; 2,1,3, 2; 3,1,3, 1; + { 0 , 0 , STBVF_u , STBVF_u }, // 0,2,3,5; 1,2,3, 4; 2,2,3, 3; 3,2,3, 2; + { 0 , 0 , 0 , STBVF_u }, // 0,3,3,6; 1,3,3, 5; 2,3,3, 4; 3,3,3, 3; + } +}; + +// these tables were constructed automatically using a variant of the code +// below; however, they seem wrong, so who knows +static unsigned char stbvox_face_up_normal_012[4][4][4] = +{ + { + { STBVF_u , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, }, + { STBVF_wu , STBVF_nu , STBVF_ne_u, STBVF_ne_u, }, + { STBVF_wu , STBVF_nw_u, STBVF_nu , STBVF_ne_u, }, + { STBVF_wu , STBVF_nw_u, STBVF_nw_u, STBVF_nu , }, + },{ + { STBVF_su , STBVF_eu , STBVF_ne_u, STBVF_ne_u, }, + { STBVF_sw_u, STBVF_u , STBVF_ne_u, STBVF_ne_u, }, + { STBVF_sw_u, STBVF_wu , STBVF_nu , STBVF_ne_u, }, + { STBVF_sw_u, STBVF_wu , STBVF_nw_u, STBVF_nu , }, + },{ + { STBVF_su , STBVF_eu , STBVF_eu , STBVF_ne_u, }, + { STBVF_sw_u, STBVF_su , STBVF_eu , STBVF_ne_u, }, + { STBVF_sw_u, STBVF_sw_u, STBVF_u , STBVF_ne_u, }, + { STBVF_sw_u, STBVF_sw_u, STBVF_wu , STBVF_nu , }, + },{ + { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , }, + { STBVF_sw_u, STBVF_su , STBVF_eu , STBVF_eu , }, + { STBVF_sw_u, STBVF_sw_u, STBVF_su , STBVF_eu , }, + { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_u , }, + } +}; + +static unsigned char stbvox_face_up_normal_013[4][4][4] = +{ + { + { STBVF_u , STBVF_eu , STBVF_eu , STBVF_eu , }, + { STBVF_nw_u, STBVF_nu , STBVF_ne_u, STBVF_ne_u, }, + { STBVF_nw_u, STBVF_nw_u, STBVF_nu , STBVF_ne_u, }, + { STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, STBVF_nu , }, + },{ + { STBVF_su , STBVF_eu , STBVF_eu , STBVF_eu , }, + { STBVF_wu , STBVF_u , STBVF_eu , STBVF_eu , }, + { STBVF_nw_u, STBVF_nw_u, STBVF_nu , STBVF_ne_u, }, + { STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, STBVF_nu , }, + },{ + { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , }, + { STBVF_sw_u, STBVF_su , STBVF_eu , STBVF_eu , }, + { STBVF_wu , STBVF_wu , STBVF_u , STBVF_eu , }, + { STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, STBVF_nu , }, + },{ + { STBVF_su , STBVF_su , STBVF_su , STBVF_eu , }, + { STBVF_sw_u, STBVF_su , STBVF_su , STBVF_su , }, + { STBVF_sw_u, STBVF_sw_u, STBVF_su , STBVF_eu , }, + { STBVF_wu , STBVF_wu , STBVF_wu , STBVF_u , }, + } +}; + +static unsigned char stbvox_face_up_normal_023[4][4][4] = +{ + { + { STBVF_u , STBVF_nu , STBVF_nu , STBVF_nu , }, + { STBVF_eu , STBVF_eu , STBVF_ne_u, STBVF_ne_u, }, + { STBVF_su , STBVF_eu , STBVF_eu , STBVF_ne_u, }, + { STBVF_eu , STBVF_eu , STBVF_eu , STBVF_eu , }, + },{ + { STBVF_wu , STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, }, + { STBVF_su , STBVF_u , STBVF_nu , STBVF_nu , }, + { STBVF_su , STBVF_eu , STBVF_eu , STBVF_ne_u, }, + { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , }, + },{ + { STBVF_wu , STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, }, + { STBVF_sw_u, STBVF_wu , STBVF_nw_u, STBVF_nw_u, }, + { STBVF_su , STBVF_su , STBVF_u , STBVF_nu , }, + { STBVF_su , STBVF_su , STBVF_eu , STBVF_eu , }, + },{ + { STBVF_wu , STBVF_nw_u, STBVF_nw_u, STBVF_nw_u, }, + { STBVF_sw_u, STBVF_wu , STBVF_nw_u, STBVF_nw_u, }, + { STBVF_sw_u, STBVF_sw_u, STBVF_wu , STBVF_nw_u, }, + { STBVF_su , STBVF_su , STBVF_su , STBVF_u , }, + } +}; + +static unsigned char stbvox_face_up_normal_123[4][4][4] = +{ + { + { STBVF_u , STBVF_nu , STBVF_nu , STBVF_nu , }, + { STBVF_eu , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, }, + { STBVF_eu , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, }, + { STBVF_eu , STBVF_ne_u, STBVF_ne_u, STBVF_ne_u, }, + },{ + { STBVF_sw_u, STBVF_wu , STBVF_nw_u, STBVF_nw_u, }, + { STBVF_su , STBVF_u , STBVF_nu , STBVF_nu , }, + { STBVF_eu , STBVF_eu , STBVF_ne_u, STBVF_ne_u, }, + { STBVF_eu , STBVF_eu , STBVF_ne_u, STBVF_ne_u, }, + },{ + { STBVF_sw_u, STBVF_sw_u, STBVF_wu , STBVF_nw_u, }, + { STBVF_sw_u, STBVF_sw_u, STBVF_wu , STBVF_nw_u, }, + { STBVF_su , STBVF_su , STBVF_u , STBVF_nu , }, + { STBVF_su , STBVF_eu , STBVF_eu , STBVF_ne_u, }, + },{ + { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_wu , }, + { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_wu , }, + { STBVF_sw_u, STBVF_sw_u, STBVF_sw_u, STBVF_wu , }, + { STBVF_su , STBVF_su , STBVF_su , STBVF_u , }, + } +}; +#endif + +void stbvox_get_quad_vertex_pointer(stbvox_mesh_maker *mm, int mesh, stbvox_mesh_vertex **vertices, stbvox_mesh_face face) +{ + char *p = mm->output_cur[mesh][0]; + int step = mm->output_step[mesh][0]; + + // allocate a new quad from the mesh + vertices[0] = (stbvox_mesh_vertex *) p; p += step; + vertices[1] = (stbvox_mesh_vertex *) p; p += step; + vertices[2] = (stbvox_mesh_vertex *) p; p += step; + vertices[3] = (stbvox_mesh_vertex *) p; p += step; + mm->output_cur[mesh][0] = p; + + // output the face + #ifdef STBVOX_ICONFIG_FACE_ATTRIBUTE + // write face as interleaved vertex data + *(stbvox_mesh_face *) (vertices[0]+1) = face; + *(stbvox_mesh_face *) (vertices[1]+1) = face; + *(stbvox_mesh_face *) (vertices[2]+1) = face; + *(stbvox_mesh_face *) (vertices[3]+1) = face; + #else + *(stbvox_mesh_face *) mm->output_cur[mesh][1] = face; + mm->output_cur[mesh][1] += 4; + #endif +} + +void stbvox_make_mesh_for_face(stbvox_mesh_maker *mm, stbvox_rotate rot, int face, int v_off, stbvox_pos pos, stbvox_mesh_vertex vertbase, stbvox_mesh_vertex *face_coord, unsigned char mesh, int normal) +{ + stbvox_mesh_face face_data = stbvox_compute_mesh_face_value(mm,rot,face,v_off, normal); + + // still need to compute ao & texlerp for each vertex + + // first compute texlerp into p1 + stbvox_mesh_vertex p1[4] = { 0 }; + + #if defined(STBVOX_CONFIG_DOWN_TEXLERP_PACKED) && defined(STBVOX_CONFIG_UP_TEXLERP_PACKED) + #define STBVOX_USE_PACKED(f) ((f) == STBVOX_FACE_up || (f) == STBVOX_FACE_down) + #elif defined(STBVOX_CONFIG_UP_TEXLERP_PACKED) + #define STBVOX_USE_PACKED(f) ((f) == STBVOX_FACE_up ) + #elif defined(STBVOX_CONFIG_DOWN_TEXLERP_PACKED) + #define STBVOX_USE_PACKED(f) ( (f) == STBVOX_FACE_down) + #endif + + #if defined(STBVOX_CONFIG_DOWN_TEXLERP_PACKED) || defined(STBVOX_CONFIG_UP_TEXLERP_PACKED) + if (STBVOX_USE_PACKED(face)) { + if (!mm->input.packed_compact || 0==(mm->input.packed_compact[v_off]&16)) + goto set_default; + p1[0] = (mm->input.packed_compact[v_off + mm->cube_vertex_offset[face][0]] >> 5); + p1[1] = (mm->input.packed_compact[v_off + mm->cube_vertex_offset[face][1]] >> 5); + p1[2] = (mm->input.packed_compact[v_off + mm->cube_vertex_offset[face][2]] >> 5); + p1[3] = (mm->input.packed_compact[v_off + mm->cube_vertex_offset[face][3]] >> 5); + p1[0] = stbvox_vertex_encode(0,0,0,0,p1[0]); + p1[1] = stbvox_vertex_encode(0,0,0,0,p1[1]); + p1[2] = stbvox_vertex_encode(0,0,0,0,p1[2]); + p1[3] = stbvox_vertex_encode(0,0,0,0,p1[3]); + goto skip; + } + #endif + + if (mm->input.block_texlerp) { + stbvox_block_type bt = mm->input.blocktype[v_off]; + unsigned char val = mm->input.block_texlerp[bt]; + p1[0] = p1[1] = p1[2] = p1[3] = stbvox_vertex_encode(0,0,0,0,val); + } else if (mm->input.block_texlerp_face) { + stbvox_block_type bt = mm->input.blocktype[v_off]; + unsigned char bt_face = STBVOX_ROTATE(face, rot.block); + unsigned char val = mm->input.block_texlerp_face[bt][bt_face]; + p1[0] = p1[1] = p1[2] = p1[3] = stbvox_vertex_encode(0,0,0,0,val); + } else if (mm->input.texlerp_face3) { + unsigned char val = (mm->input.texlerp_face3[v_off] >> stbvox_face3_lerp[face]) & 7; + if (face >= STBVOX_FACE_up) + val = stbvox_face3_updown[val]; + p1[0] = p1[1] = p1[2] = p1[3] = stbvox_vertex_encode(0,0,0,0,val); + } else if (mm->input.texlerp_simple) { + unsigned char val = mm->input.texlerp_simple[v_off]; + unsigned char lerp_face = (val >> 2) & 7; + if (lerp_face == face) { + p1[0] = (mm->input.texlerp_simple[v_off + mm->cube_vertex_offset[face][0]] >> 5) & 7; + p1[1] = (mm->input.texlerp_simple[v_off + mm->cube_vertex_offset[face][1]] >> 5) & 7; + p1[2] = (mm->input.texlerp_simple[v_off + mm->cube_vertex_offset[face][2]] >> 5) & 7; + p1[3] = (mm->input.texlerp_simple[v_off + mm->cube_vertex_offset[face][3]] >> 5) & 7; + p1[0] = stbvox_vertex_encode(0,0,0,0,p1[0]); + p1[1] = stbvox_vertex_encode(0,0,0,0,p1[1]); + p1[2] = stbvox_vertex_encode(0,0,0,0,p1[2]); + p1[3] = stbvox_vertex_encode(0,0,0,0,p1[3]); + } else { + unsigned char base = stbvox_vert_lerp_for_simple[val&3]; + p1[0] = p1[1] = p1[2] = p1[3] = stbvox_vertex_encode(0,0,0,0,base); + } + } else if (mm->input.texlerp) { + unsigned char facelerp = (mm->input.texlerp[v_off] >> stbvox_face_lerp[face]) & 3; + if (facelerp == STBVOX_TEXLERP_FACE_use_vert) { + if (mm->input.texlerp_vert3 && face != STBVOX_FACE_down) { + unsigned char shift = stbvox_vert3_lerp[face]; + p1[0] = (mm->input.texlerp_vert3[mm->cube_vertex_offset[face][0]] >> shift) & 7; + p1[1] = (mm->input.texlerp_vert3[mm->cube_vertex_offset[face][1]] >> shift) & 7; + p1[2] = (mm->input.texlerp_vert3[mm->cube_vertex_offset[face][2]] >> shift) & 7; + p1[3] = (mm->input.texlerp_vert3[mm->cube_vertex_offset[face][3]] >> shift) & 7; + } else { + p1[0] = stbvox_vert_lerp_for_simple[mm->input.texlerp[mm->cube_vertex_offset[face][0]]>>6]; + p1[1] = stbvox_vert_lerp_for_simple[mm->input.texlerp[mm->cube_vertex_offset[face][1]]>>6]; + p1[2] = stbvox_vert_lerp_for_simple[mm->input.texlerp[mm->cube_vertex_offset[face][2]]>>6]; + p1[3] = stbvox_vert_lerp_for_simple[mm->input.texlerp[mm->cube_vertex_offset[face][3]]>>6]; + } + p1[0] = stbvox_vertex_encode(0,0,0,0,p1[0]); + p1[1] = stbvox_vertex_encode(0,0,0,0,p1[1]); + p1[2] = stbvox_vertex_encode(0,0,0,0,p1[2]); + p1[3] = stbvox_vertex_encode(0,0,0,0,p1[3]); + } else { + p1[0] = p1[1] = p1[2] = p1[3] = stbvox_vertex_encode(0,0,0,0,stbvox_vert_lerp_for_face_lerp[facelerp]); + } + } else { + #if defined(STBVOX_CONFIG_UP_TEXLERP_PACKED) || defined(STBVOX_CONFIG_DOWN_TEXLERP_PACKED) + set_default: + #endif + p1[0] = p1[1] = p1[2] = p1[3] = stbvox_vertex_encode(0,0,0,0,7); // @TODO make this configurable + } + + #if defined(STBVOX_CONFIG_UP_TEXLERP_PACKED) || defined(STBVOX_CONFIG_DOWN_TEXLERP_PACKED) + skip: + #endif + + // now compute lighting and store to vertices + { + stbvox_mesh_vertex *mv[4]; + stbvox_get_quad_vertex_pointer(mm, mesh, mv, face_data); + + if (mm->input.lighting) { + // @TODO: lighting at block centers, but not gathered, instead constant-per-face + if (mm->input.lighting_at_vertices) { + int i; + for (i=0; i < 4; ++i) { + *mv[i] = vertbase + face_coord[i] + + stbvox_vertex_encode(0,0,0,mm->input.lighting[v_off + mm->cube_vertex_offset[face][i]] & 63,0) + + p1[i]; + } + } else { + unsigned char *amb = &mm->input.lighting[v_off]; + int i,j; + #if defined(STBVOX_CONFIG_ROTATION_IN_LIGHTING) || defined(STBVOX_CONFIG_VHEIGHT_IN_LIGHTING) + #define STBVOX_GET_LIGHTING(light) ((light) & ~3) + #define STBVOX_LIGHTING_ROUNDOFF 8 + #else + #define STBVOX_GET_LIGHTING(light) (light) + #define STBVOX_LIGHTING_ROUNDOFF 2 + #endif + + for (i=0; i < 4; ++i) { + // for each vertex, gather from the four neighbor blocks it's facing + unsigned char *vamb = &amb[mm->cube_vertex_offset[face][i]]; + int total=0; + for (j=0; j < 4; ++j) + total += STBVOX_GET_LIGHTING(vamb[mm->vertex_gather_offset[face][j]]); + *mv[i] = vertbase + face_coord[i] + + stbvox_vertex_encode(0,0,0,(total+STBVOX_LIGHTING_ROUNDOFF)>>4,0) + + p1[i]; + // >> 4 is because: + // >> 2 to divide by 4 to get average over 4 samples + // >> 2 because input is 8 bits, output is 6 bits + } + + // @TODO: note that gathering baked *lighting* + // is different from gathering baked ao; baked ao can count + // solid blocks as 0 ao, but baked lighting wants average + // of non-blocked--not take average & treat blocked as 0. And + // we can't bake the right value into the solid blocks + // because they can have different lighting values on + // different sides. So we need to actually gather and + // then divide by 0..4 (which we can do with a table-driven + // multiply, or have an 'if' for the 3 case) + + } + } else { + vertbase += stbvox_vertex_encode(0,0,0,63,0); + *mv[0] = vertbase + face_coord[0] + p1[0]; + *mv[1] = vertbase + face_coord[1] + p1[1]; + *mv[2] = vertbase + face_coord[2] + p1[2]; + *mv[3] = vertbase + face_coord[3] + p1[3]; + } + } +} + +// get opposite-facing normal & texgen for opposite face, used to map up-facing vheight data to down-facing data +static unsigned char stbvox_reverse_face[STBVF_count] = +{ + STBVF_w, STBVF_s, STBVF_e, STBVF_n, STBVF_d , STBVF_u , STBVF_wd, STBVF_wu, + 0, 0, 0, 0, STBVF_sw_d, STBVF_sw_u, STBVF_sd, STBVF_su, + 0, 0, 0, 0, STBVF_se_d, STBVF_se_u, STBVF_ed, STBVF_eu, + 0, 0, 0, 0, STBVF_ne_d, STBVF_ne_d, STBVF_nd, STBVF_nu +}; + +#ifndef STBVOX_CONFIG_OPTIMIZED_VHEIGHT +// render non-planar quads by splitting into two triangles, rendering each as a degenerate quad +static void stbvox_make_12_split_mesh_for_face(stbvox_mesh_maker *mm, stbvox_rotate rot, int face, int v_off, stbvox_pos pos, stbvox_mesh_vertex vertbase, stbvox_mesh_vertex *face_coord, unsigned char mesh, unsigned char *ht) +{ + stbvox_mesh_vertex v[4]; + + unsigned char normal1 = stbvox_face_up_normal_012[ht[2]][ht[1]][ht[0]]; + unsigned char normal2 = stbvox_face_up_normal_123[ht[3]][ht[2]][ht[1]]; + + if (face == STBVOX_FACE_down) { + normal1 = stbvox_reverse_face[normal1]; + normal2 = stbvox_reverse_face[normal2]; + } + + // the floor side face_coord is stored in order NW,NE,SE,SW, but ht[] is stored SW,SE,NW,NE + v[0] = face_coord[2]; + v[1] = face_coord[3]; + v[2] = face_coord[0]; + v[3] = face_coord[2]; + stbvox_make_mesh_for_face(mm, rot, face, v_off, pos, vertbase, v, mesh, normal1); + v[1] = face_coord[0]; + v[2] = face_coord[1]; + stbvox_make_mesh_for_face(mm, rot, face, v_off, pos, vertbase, v, mesh, normal2); +} + +static void stbvox_make_03_split_mesh_for_face(stbvox_mesh_maker *mm, stbvox_rotate rot, int face, int v_off, stbvox_pos pos, stbvox_mesh_vertex vertbase, stbvox_mesh_vertex *face_coord, unsigned char mesh, unsigned char *ht) +{ + stbvox_mesh_vertex v[4]; + + unsigned char normal1 = stbvox_face_up_normal_013[ht[3]][ht[1]][ht[0]]; + unsigned char normal2 = stbvox_face_up_normal_023[ht[3]][ht[2]][ht[0]]; + + if (face == STBVOX_FACE_down) { + normal1 = stbvox_reverse_face[normal1]; + normal2 = stbvox_reverse_face[normal2]; + } + + v[0] = face_coord[1]; + v[1] = face_coord[2]; + v[2] = face_coord[3]; + v[3] = face_coord[1]; + stbvox_make_mesh_for_face(mm, rot, face, v_off, pos, vertbase, v, mesh, normal1); + v[1] = face_coord[3]; + v[2] = face_coord[0]; + stbvox_make_mesh_for_face(mm, rot, face, v_off, pos, vertbase, v, mesh, normal2); // this one is correct! +} +#endif + +#ifndef STBVOX_CONFIG_PRECISION_Z +#define STBVOX_CONFIG_PRECISION_Z 1 +#endif + +// simple case for mesh generation: we have only solid and empty blocks +static void stbvox_make_mesh_for_block(stbvox_mesh_maker *mm, stbvox_pos pos, int v_off, stbvox_mesh_vertex *vmesh) +{ + int ns_off = mm->y_stride_in_bytes; + int ew_off = mm->x_stride_in_bytes; + + unsigned char *blockptr = &mm->input.blocktype[v_off]; + stbvox_mesh_vertex basevert = stbvox_vertex_encode(pos.x, pos.y, pos.z << STBVOX_CONFIG_PRECISION_Z , 0,0); + + stbvox_rotate rot = { 0,0,0,0 }; + unsigned char simple_rot = 0; + + unsigned char mesh = mm->default_mesh; + + if (mm->input.selector) + mesh = mm->input.selector[v_off]; + else if (mm->input.block_selector) + mesh = mm->input.block_selector[mm->input.blocktype[v_off]]; + + // check if we're going off the end + if (mm->output_cur[mesh][0] + mm->output_size[mesh][0]*6 > mm->output_end[mesh][0]) { + mm->full = 1; + return; + } + + #ifdef STBVOX_CONFIG_ROTATION_IN_LIGHTING + simple_rot = mm->input.lighting[v_off] & 3; + #endif + + if (mm->input.packed_compact) + simple_rot = mm->input.packed_compact[v_off] & 3; + + if (blockptr[ 1]==0) { + rot.facerot = simple_rot; + stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_up , v_off, pos, basevert, vmesh+4*STBVOX_FACE_up, mesh, STBVOX_FACE_up); + } + if (blockptr[-1]==0) { + rot.facerot = (-simple_rot) & 3; + stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_down, v_off, pos, basevert, vmesh+4*STBVOX_FACE_down, mesh, STBVOX_FACE_down); + } + + if (mm->input.rotate) { + unsigned char val = mm->input.rotate[v_off]; + rot.block = (val >> 0) & 3; + rot.overlay = (val >> 2) & 3; + //rot.tex2 = (val >> 4) & 3; + rot.ecolor = (val >> 6) & 3; + } else { + rot.block = rot.overlay = rot.ecolor = simple_rot; + } + rot.facerot = 0; + + if (blockptr[ ns_off]==0) + stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_north, v_off, pos, basevert, vmesh+4*STBVOX_FACE_north, mesh, STBVOX_FACE_north); + if (blockptr[-ns_off]==0) + stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_south, v_off, pos, basevert, vmesh+4*STBVOX_FACE_south, mesh, STBVOX_FACE_south); + if (blockptr[ ew_off]==0) + stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_east , v_off, pos, basevert, vmesh+4*STBVOX_FACE_east, mesh, STBVOX_FACE_east); + if (blockptr[-ew_off]==0) + stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_west , v_off, pos, basevert, vmesh+4*STBVOX_FACE_west, mesh, STBVOX_FACE_west); +} + +// complex case for mesh generation: we have lots of different +// block types, and we don't want to generate faces of blocks +// if they're hidden by neighbors. +// +// we use lots of tables to determine this: we have a table +// which tells us what face type is generated for each type of +// geometry, and then a table that tells us whether that type +// is hidden by a neighbor. +static void stbvox_make_mesh_for_block_with_geo(stbvox_mesh_maker *mm, stbvox_pos pos, int v_off) +{ + int ns_off = mm->y_stride_in_bytes; + int ew_off = mm->x_stride_in_bytes; + int visible_faces, visible_base; + unsigned char mesh; + + // first gather the geometry info for this block and all neighbors + + unsigned char bt, nbt[6]; + unsigned char geo, ngeo[6]; + unsigned char rot, nrot[6]; + + bt = mm->input.blocktype[v_off]; + nbt[0] = mm->input.blocktype[v_off + ew_off]; + nbt[1] = mm->input.blocktype[v_off + ns_off]; + nbt[2] = mm->input.blocktype[v_off - ew_off]; + nbt[3] = mm->input.blocktype[v_off - ns_off]; + nbt[4] = mm->input.blocktype[v_off + 1]; + nbt[5] = mm->input.blocktype[v_off - 1]; + if (mm->input.geometry) { + int i; + geo = mm->input.geometry[v_off]; + ngeo[0] = mm->input.geometry[v_off + ew_off]; + ngeo[1] = mm->input.geometry[v_off + ns_off]; + ngeo[2] = mm->input.geometry[v_off - ew_off]; + ngeo[3] = mm->input.geometry[v_off - ns_off]; + ngeo[4] = mm->input.geometry[v_off + 1]; + ngeo[5] = mm->input.geometry[v_off - 1]; + + rot = (geo >> 4) & 3; + geo &= 15; + for (i=0; i < 6; ++i) { + nrot[i] = (ngeo[i] >> 4) & 3; + ngeo[i] &= 15; + } + } else { + int i; + assert(mm->input.block_geometry); + geo = mm->input.block_geometry[bt]; + for (i=0; i < 6; ++i) + ngeo[i] = mm->input.block_geometry[nbt[i]]; + if (mm->input.selector) { + #ifndef STBVOX_CONFIG_ROTATION_IN_LIGHTING + if (mm->input.packed_compact == NULL) { + rot = (mm->input.selector[v_off ] >> 4) & 3; + nrot[0] = (mm->input.selector[v_off + ew_off] >> 4) & 3; + nrot[1] = (mm->input.selector[v_off + ns_off] >> 4) & 3; + nrot[2] = (mm->input.selector[v_off - ew_off] >> 4) & 3; + nrot[3] = (mm->input.selector[v_off - ns_off] >> 4) & 3; + nrot[4] = (mm->input.selector[v_off + 1] >> 4) & 3; + nrot[5] = (mm->input.selector[v_off - 1] >> 4) & 3; + } + #endif + } else { + #ifndef STBVOX_CONFIG_ROTATION_IN_LIGHTING + if (mm->input.packed_compact == NULL) { + rot = (geo>>4)&3; + geo &= 15; + for (i=0; i < 6; ++i) { + nrot[i] = (ngeo[i]>>4)&3; + ngeo[i] &= 15; + } + } + #endif + } + } + + #ifndef STBVOX_CONFIG_ROTATION_IN_LIGHTING + if (mm->input.packed_compact) { + rot = mm->input.packed_compact[rot] & 3; + nrot[0] = mm->input.packed_compact[v_off + ew_off] & 3; + nrot[1] = mm->input.packed_compact[v_off + ns_off] & 3; + nrot[2] = mm->input.packed_compact[v_off - ew_off] & 3; + nrot[3] = mm->input.packed_compact[v_off - ns_off] & 3; + nrot[4] = mm->input.packed_compact[v_off + 1] & 3; + nrot[5] = mm->input.packed_compact[v_off - 1] & 3; + } + #else + rot = mm->input.lighting[v_off] & 3; + nrot[0] = (mm->input.lighting[v_off + ew_off]) & 3; + nrot[1] = (mm->input.lighting[v_off + ns_off]) & 3; + nrot[2] = (mm->input.lighting[v_off - ew_off]) & 3; + nrot[3] = (mm->input.lighting[v_off - ns_off]) & 3; + nrot[4] = (mm->input.lighting[v_off + 1]) & 3; + nrot[5] = (mm->input.lighting[v_off - 1]) & 3; + #endif + + if (geo == STBVOX_GEOM_transp) { + // transparency has a special rule: if the blocktype is the same, + // and the faces are compatible, then can hide them; otherwise, + // force them on + // Note that this means we don't support any transparentshapes other + // than solid blocks, since detecting them is too complicated. If + // you wanted to do something like minecraft water, you probably + // should just do that with a separate renderer anyway. (We don't + // support transparency sorting so you need to use alpha test + // anyway) + int i; + for (i=0; i < 6; ++i) + if (nbt[i] != bt) { + nbt[i] = 0; + ngeo[i] = STBVOX_GEOM_empty; + } else + ngeo[i] = STBVOX_GEOM_solid; + geo = STBVOX_GEOM_solid; + } + + // now compute the face visibility + visible_base = stbvox_hasface[geo][rot]; + // @TODO: assert(visible_base != 0); // we should have early-outted earlier in this case + visible_faces = 0; + + // now, for every face that might be visible, check if neighbor hides it + if (visible_base & (1 << STBVOX_FACE_east)) { + int type = stbvox_facetype[ geo ][(STBVOX_FACE_east+ rot )&3]; + int ntype = stbvox_facetype[ngeo[0]][(STBVOX_FACE_west+nrot[0])&3]; + visible_faces |= ((stbvox_face_visible[type]) >> (ntype + 5 - STBVOX_FACE_east)) & (1 << STBVOX_FACE_east); + } + if (visible_base & (1 << STBVOX_FACE_north)) { + int type = stbvox_facetype[ geo ][(STBVOX_FACE_north+ rot )&3]; + int ntype = stbvox_facetype[ngeo[1]][(STBVOX_FACE_south+nrot[1])&3]; + visible_faces |= ((stbvox_face_visible[type]) >> (ntype + 5 - STBVOX_FACE_north)) & (1 << STBVOX_FACE_north); + } + if (visible_base & (1 << STBVOX_FACE_west)) { + int type = stbvox_facetype[ geo ][(STBVOX_FACE_west+ rot )&3]; + int ntype = stbvox_facetype[ngeo[2]][(STBVOX_FACE_east+nrot[2])&3]; + visible_faces |= ((stbvox_face_visible[type]) >> (ntype + 5 - STBVOX_FACE_west)) & (1 << STBVOX_FACE_west); + } + if (visible_base & (1 << STBVOX_FACE_south)) { + int type = stbvox_facetype[ geo ][(STBVOX_FACE_south+ rot )&3]; + int ntype = stbvox_facetype[ngeo[3]][(STBVOX_FACE_north+nrot[3])&3]; + visible_faces |= ((stbvox_face_visible[type]) >> (ntype + 5 - STBVOX_FACE_south)) & (1 << STBVOX_FACE_south); + } + if (visible_base & (1 << STBVOX_FACE_up)) { + int type = stbvox_facetype[ geo ][STBVOX_FACE_up]; + int ntype = stbvox_facetype[ngeo[4]][STBVOX_FACE_down]; + visible_faces |= ((stbvox_face_visible[type]) >> (ntype + 5 - STBVOX_FACE_up)) & (1 << STBVOX_FACE_up); + } + if (visible_base & (1 << STBVOX_FACE_down)) { + int type = stbvox_facetype[ geo ][STBVOX_FACE_down]; + int ntype = stbvox_facetype[ngeo[5]][STBVOX_FACE_up]; + visible_faces |= ((stbvox_face_visible[type]) >> (ntype + 5 - STBVOX_FACE_down)) & (1 << STBVOX_FACE_down); + } + + if (geo == STBVOX_GEOM_force) + geo = STBVOX_GEOM_solid; + + assert((geo == STBVOX_GEOM_crossed_pair) ? (visible_faces == 15) : 1); + + // now we finally know for sure which faces are getting generated + if (visible_faces == 0) + return; + + mesh = mm->default_mesh; + if (mm->input.selector) + mesh = mm->input.selector[v_off]; + else if (mm->input.block_selector) + mesh = mm->input.block_selector[bt]; + + if (geo <= STBVOX_GEOM_ceil_slope_north_is_bottom) { + // this is the simple case, we can just use regular block gen with special vmesh calculated with vheight + stbvox_mesh_vertex basevert; + stbvox_mesh_vertex vmesh[6][4]; + stbvox_rotate rotate = { 0,0,0,0 }; + unsigned char simple_rot = rot; + int i; + // we only need to do this for the displayed faces, but it's easier + // to just do it up front; @OPTIMIZE check if it's faster to do it + // for visible faces only + for (i=0; i < 6*4; ++i) { + int vert = stbvox_vertex_selector[0][i]; + vert = stbvox_rotate_vertex[vert][rot]; + vmesh[0][i] = stbvox_vmesh_pre_vheight[0][i] + + stbvox_geometry_vheight[geo][vert]; + } + + basevert = stbvox_vertex_encode(pos.x, pos.y, pos.z << STBVOX_CONFIG_PRECISION_Z, 0,0); + if (mm->input.selector) { + mesh = mm->input.selector[v_off]; + } else if (mm->input.block_selector) + mesh = mm->input.block_selector[bt]; + + + // check if we're going off the end + if (mm->output_cur[mesh][0] + mm->output_size[mesh][0]*6 > mm->output_end[mesh][0]) { + mm->full = 1; + return; + } + + if (geo >= STBVOX_GEOM_floor_slope_north_is_top) { + if (visible_faces & (1 << STBVOX_FACE_up)) { + int normal = geo == STBVOX_GEOM_floor_slope_north_is_top ? stbvox_floor_slope_for_rot[simple_rot] : STBVOX_FACE_up; + rotate.facerot = simple_rot; + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_up , v_off, pos, basevert, vmesh[STBVOX_FACE_up], mesh, normal); + } + if (visible_faces & (1 << STBVOX_FACE_down)) { + int normal = geo == STBVOX_GEOM_ceil_slope_north_is_bottom ? stbvox_ceil_slope_for_rot[simple_rot] : STBVOX_FACE_down; + rotate.facerot = (-rotate.facerot) & 3; + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_down, v_off, pos, basevert, vmesh[STBVOX_FACE_down], mesh, normal); + } + } else { + if (visible_faces & (1 << STBVOX_FACE_up)) { + rotate.facerot = simple_rot; + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_up , v_off, pos, basevert, vmesh[STBVOX_FACE_up], mesh, STBVOX_FACE_up); + } + if (visible_faces & (1 << STBVOX_FACE_down)) { + rotate.facerot = (-rotate.facerot) & 3; + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_down, v_off, pos, basevert, vmesh[STBVOX_FACE_down], mesh, STBVOX_FACE_down); + } + } + + if (mm->input.rotate) { + unsigned char val = mm->input.rotate[v_off]; + rotate.block = (val >> 0) & 3; + rotate.overlay = (val >> 2) & 3; + //rotate.tex2 = (val >> 4) & 3; + rotate.ecolor = (val >> 6) & 3; + } else { + rotate.block = rotate.overlay = rotate.ecolor = simple_rot; + } + + rotate.facerot = 0; + + if (visible_faces & (1 << STBVOX_FACE_north)) + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_north, v_off, pos, basevert, vmesh[STBVOX_FACE_north], mesh, STBVOX_FACE_north); + if (visible_faces & (1 << STBVOX_FACE_south)) + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_south, v_off, pos, basevert, vmesh[STBVOX_FACE_south], mesh, STBVOX_FACE_south); + if (visible_faces & (1 << STBVOX_FACE_east)) + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_east , v_off, pos, basevert, vmesh[STBVOX_FACE_east ], mesh, STBVOX_FACE_east); + if (visible_faces & (1 << STBVOX_FACE_west)) + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_west , v_off, pos, basevert, vmesh[STBVOX_FACE_west ], mesh, STBVOX_FACE_west); + } + if (geo >= STBVOX_GEOM_floor_vheight_03) { + // this case can also be generated with regular block gen with special vmesh, + // except: + // if we want to generate middle diagonal for 'weird' blocks + // it's more complicated to detect neighbor matchups + stbvox_mesh_vertex vmesh[6][4]; + stbvox_mesh_vertex cube[8]; + stbvox_mesh_vertex basevert; + stbvox_rotate rotate = { 0,0,0,0 }; + unsigned char simple_rot = rot; + unsigned char ht[4]; + int extreme; + + // extract the heights + #ifdef STBVOX_CONFIG_VHEIGHT_IN_LIGHTING + ht[0] = mm->input.lighting[v_off ] & 3; + ht[1] = mm->input.lighting[v_off+ew_off ] & 3; + ht[2] = mm->input.lighting[v_off +ns_off] & 3; + ht[3] = mm->input.lighting[v_off+ew_off+ns_off] & 3; + #else + if (mm->input.vheight) { + unsigned char v = mm->input.vheight[v_off]; + ht[0] = (v >> 0) & 3; + ht[1] = (v >> 2) & 3; + ht[2] = (v >> 4) & 3; + ht[3] = (v >> 6) & 3; + } else if (mm->input.block_vheight) { + unsigned char v = mm->input.block_vheight[bt]; + unsigned char raw[4]; + int i; + + raw[0] = (v >> 0) & 3; + raw[1] = (v >> 2) & 3; + raw[2] = (v >> 4) & 3; + raw[3] = (v >> 6) & 3; + + for (i=0; i < 4; ++i) + ht[i] = raw[stbvox_rotate_vertex[i][rot]]; + } else if (mm->input.packed_compact) { + ht[0] = (mm->input.packed_compact[v_off ] >> 2) & 3; + ht[1] = (mm->input.packed_compact[v_off+ew_off ] >> 2) & 3; + ht[2] = (mm->input.packed_compact[v_off +ns_off] >> 2) & 3; + ht[3] = (mm->input.packed_compact[v_off+ew_off+ns_off] >> 2) & 3; + } else if (mm->input.geometry) { + ht[0] = mm->input.geometry[v_off ] >> 6; + ht[1] = mm->input.geometry[v_off+ew_off ] >> 6; + ht[2] = mm->input.geometry[v_off +ns_off] >> 6; + ht[3] = mm->input.geometry[v_off+ew_off+ns_off] >> 6; + } else { + assert(0); + } + #endif + + // flag whether any sides go off the top of the block, which means + // our visible_faces test was wrong + extreme = (ht[0] == 3 || ht[1] == 3 || ht[2] == 3 || ht[3] == 3); + + if (geo >= STBVOX_GEOM_ceil_vheight_03) { + cube[0] = stbvox_vertex_encode(0,0,ht[0],0,0); + cube[1] = stbvox_vertex_encode(0,0,ht[1],0,0); + cube[2] = stbvox_vertex_encode(0,0,ht[2],0,0); + cube[3] = stbvox_vertex_encode(0,0,ht[3],0,0); + cube[4] = stbvox_vertex_encode(0,0,2,0,0); + cube[5] = stbvox_vertex_encode(0,0,2,0,0); + cube[6] = stbvox_vertex_encode(0,0,2,0,0); + cube[7] = stbvox_vertex_encode(0,0,2,0,0); + } else { + cube[0] = stbvox_vertex_encode(0,0,0,0,0); + cube[1] = stbvox_vertex_encode(0,0,0,0,0); + cube[2] = stbvox_vertex_encode(0,0,0,0,0); + cube[3] = stbvox_vertex_encode(0,0,0,0,0); + cube[4] = stbvox_vertex_encode(0,0,ht[0],0,0); + cube[5] = stbvox_vertex_encode(0,0,ht[1],0,0); + cube[6] = stbvox_vertex_encode(0,0,ht[2],0,0); + cube[7] = stbvox_vertex_encode(0,0,ht[3],0,0); + } + if (!mm->input.vheight && mm->input.block_vheight) { + // @TODO: support block vheight here, I've forgotten what needs to be done specially + } + + // build vertex mesh + { + int i; + for (i=0; i < 6*4; ++i) { + int vert = stbvox_vertex_selector[0][i]; + vmesh[0][i] = stbvox_vmesh_pre_vheight[0][i] + + cube[vert]; + } + } + + basevert = stbvox_vertex_encode(pos.x, pos.y, pos.z << STBVOX_CONFIG_PRECISION_Z, 0,0); + // check if we're going off the end + if (mm->output_cur[mesh][0] + mm->output_size[mesh][0]*6 > mm->output_end[mesh][0]) { + mm->full = 1; + return; + } + + // @TODO generate split faces + if (visible_faces & (1 << STBVOX_FACE_up)) { + if (geo >= STBVOX_GEOM_ceil_vheight_03) + // flat + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_up , v_off, pos, basevert, vmesh[STBVOX_FACE_up], mesh, STBVOX_FACE_up); + else { + #ifndef STBVOX_CONFIG_OPTIMIZED_VHEIGHT + // check if it's non-planar + if (cube[5] + cube[6] != cube[4] + cube[7]) { + // not planar, split along diagonal and make degenerate quads + if (geo == STBVOX_GEOM_floor_vheight_03) + stbvox_make_03_split_mesh_for_face(mm, rotate, STBVOX_FACE_up, v_off, pos, basevert, vmesh[STBVOX_FACE_up], mesh, ht); + else + stbvox_make_12_split_mesh_for_face(mm, rotate, STBVOX_FACE_up, v_off, pos, basevert, vmesh[STBVOX_FACE_up], mesh, ht); + } else + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_up , v_off, pos, basevert, vmesh[STBVOX_FACE_up], mesh, stbvox_planar_face_up_normal[ht[2]][ht[1]][ht[0]]); + #else + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_up , v_off, pos, basevert, vmesh[STBVOX_FACE_up], mesh, stbvox_optimized_face_up_normal[ht[3]][ht[2]][ht[1]][ht[0]]); + #endif + } + } + if (visible_faces & (1 << STBVOX_FACE_down)) { + if (geo < STBVOX_GEOM_ceil_vheight_03) + // flat + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_down, v_off, pos, basevert, vmesh[STBVOX_FACE_down], mesh, STBVOX_FACE_down); + else { + #ifndef STBVOX_CONFIG_OPTIMIZED_VHEIGHT + // check if it's non-planar + if (cube[1] + cube[2] != cube[0] + cube[3]) { + // not planar, split along diagonal and make degenerate quads + if (geo == STBVOX_GEOM_ceil_vheight_03) + stbvox_make_03_split_mesh_for_face(mm, rotate, STBVOX_FACE_down, v_off, pos, basevert, vmesh[STBVOX_FACE_down], mesh, ht); + else + stbvox_make_12_split_mesh_for_face(mm, rotate, STBVOX_FACE_down, v_off, pos, basevert, vmesh[STBVOX_FACE_down], mesh, ht); + } else + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_down, v_off, pos, basevert, vmesh[STBVOX_FACE_down], mesh, stbvox_reverse_face[stbvox_planar_face_up_normal[ht[2]][ht[1]][ht[0]]]); + #else + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_down, v_off, pos, basevert, vmesh[STBVOX_FACE_down], mesh, stbvox_reverse_face[stbvox_optimized_face_up_normal[ht[3]][ht[2]][ht[1]][ht[0]]]); + #endif + } + } + + if (mm->input.rotate) { + unsigned char val = mm->input.rotate[v_off]; + rotate.block = (val >> 0) & 3; + rotate.overlay = (val >> 2) & 3; + //rotate.tex2 = (val >> 4) & 3; + rotate.ecolor = (val >> 6) & 3; + } else if (mm->input.selector) { + rotate.block = rotate.overlay = rotate.ecolor = simple_rot; + } + + if ((visible_faces & (1 << STBVOX_FACE_north)) || (extreme && (ht[2] == 3 || ht[3] == 3))) + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_north, v_off, pos, basevert, vmesh[STBVOX_FACE_north], mesh, STBVOX_FACE_north); + if ((visible_faces & (1 << STBVOX_FACE_south)) || (extreme && (ht[0] == 3 || ht[1] == 3))) + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_south, v_off, pos, basevert, vmesh[STBVOX_FACE_south], mesh, STBVOX_FACE_south); + if ((visible_faces & (1 << STBVOX_FACE_east)) || (extreme && (ht[1] == 3 || ht[3] == 3))) + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_east , v_off, pos, basevert, vmesh[STBVOX_FACE_east ], mesh, STBVOX_FACE_east); + if ((visible_faces & (1 << STBVOX_FACE_west)) || (extreme && (ht[0] == 3 || ht[2] == 3))) + stbvox_make_mesh_for_face(mm, rotate, STBVOX_FACE_west , v_off, pos, basevert, vmesh[STBVOX_FACE_west ], mesh, STBVOX_FACE_west); + } + + if (geo == STBVOX_GEOM_crossed_pair) { + // this can be generated with a special vmesh + stbvox_mesh_vertex basevert = stbvox_vertex_encode(pos.x, pos.y, pos.z << STBVOX_CONFIG_PRECISION_Z , 0,0); + unsigned char simple_rot=0; + stbvox_rotate rot = { 0,0,0,0 }; + unsigned char mesh = mm->default_mesh; + if (mm->input.selector) { + mesh = mm->input.selector[v_off]; + simple_rot = mesh >> 4; + mesh &= 15; + } + if (mm->input.block_selector) { + mesh = mm->input.block_selector[bt]; + } + + // check if we're going off the end + if (mm->output_cur[mesh][0] + mm->output_size[mesh][0]*4 > mm->output_end[mesh][0]) { + mm->full = 1; + return; + } + + if (mm->input.rotate) { + unsigned char val = mm->input.rotate[v_off]; + rot.block = (val >> 0) & 3; + rot.overlay = (val >> 2) & 3; + //rot.tex2 = (val >> 4) & 3; + rot.ecolor = (val >> 6) & 3; + } else if (mm->input.selector) { + rot.block = rot.overlay = rot.ecolor = simple_rot; + } + rot.facerot = 0; + + stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_north, v_off, pos, basevert, stbvox_vmesh_crossed_pair[STBVOX_FACE_north], mesh, STBVF_ne_u_cross); + stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_south, v_off, pos, basevert, stbvox_vmesh_crossed_pair[STBVOX_FACE_south], mesh, STBVF_sw_u_cross); + stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_east , v_off, pos, basevert, stbvox_vmesh_crossed_pair[STBVOX_FACE_east ], mesh, STBVF_se_u_cross); + stbvox_make_mesh_for_face(mm, rot, STBVOX_FACE_west , v_off, pos, basevert, stbvox_vmesh_crossed_pair[STBVOX_FACE_west ], mesh, STBVF_nw_u_cross); + } + + + // @TODO + // STBVOX_GEOM_floor_slope_north_is_top_as_wall, + // STBVOX_GEOM_ceil_slope_north_is_bottom_as_wall, +} + +static void stbvox_make_mesh_for_column(stbvox_mesh_maker *mm, int x, int y, int z0) +{ + stbvox_pos pos; + int v_off = x * mm->x_stride_in_bytes + y * mm->y_stride_in_bytes; + int ns_off = mm->y_stride_in_bytes; + int ew_off = mm->x_stride_in_bytes; + pos.x = x; + pos.y = y; + pos.z = 0; + if (mm->input.geometry) { + unsigned char *bt = mm->input.blocktype + v_off; + unsigned char *geo = mm->input.geometry + v_off; + int z; + for (z=z0; z < mm->z1; ++z) { + if (bt[z] && ( !bt[z+ns_off] || !STBVOX_GET_GEO(geo[z+ns_off]) || !bt[z-ns_off] || !STBVOX_GET_GEO(geo[z-ns_off]) + || !bt[z+ew_off] || !STBVOX_GET_GEO(geo[z+ew_off]) || !bt[z-ew_off] || !STBVOX_GET_GEO(geo[z-ew_off]) + || !bt[z-1] || !STBVOX_GET_GEO(geo[z-1]) || !bt[z+1] || !STBVOX_GET_GEO(geo[z+1]))) + { // TODO check up and down + pos.z = z; + stbvox_make_mesh_for_block_with_geo(mm, pos, v_off+z); + if (mm->full) { + mm->cur_z = z; + return; + } + } + } + } else if (mm->input.block_geometry) { + int z; + unsigned char *bt = mm->input.blocktype + v_off; + unsigned char *geo = mm->input.block_geometry; + for (z=z0; z < mm->z1; ++z) { + if (bt[z] && ( geo[bt[z+ns_off]] != STBVOX_GEOM_solid + || geo[bt[z-ns_off]] != STBVOX_GEOM_solid + || geo[bt[z+ew_off]] != STBVOX_GEOM_solid + || geo[bt[z-ew_off]] != STBVOX_GEOM_solid + || geo[bt[z-1]] != STBVOX_GEOM_solid + || geo[bt[z+1]] != STBVOX_GEOM_solid)) + { + pos.z = z; + stbvox_make_mesh_for_block_with_geo(mm, pos, v_off+z); + if (mm->full) { + mm->cur_z = z; + return; + } + } + } + } else { + unsigned char *bt = mm->input.blocktype + v_off; + int z; + #if STBVOX_CONFIG_PRECISION_Z == 1 + stbvox_mesh_vertex *vmesh = stbvox_vmesh_delta_half_z[0]; + #else + stbvox_mesh_vertex *vmesh = stbvox_vmesh_delta_normal[0]; + #endif + for (z=z0; z < mm->z1; ++z) { + // if it's solid and at least one neighbor isn't solid + if (bt[z] && (!bt[z+ns_off] || !bt[z-ns_off] || !bt[z+ew_off] || !bt[z-ew_off] || !bt[z-1] || !bt[z+1])) { + pos.z = z; + stbvox_make_mesh_for_block(mm, pos, v_off+z, vmesh); + if (mm->full) { + mm->cur_z = z; + return; + } + } + } + } +} + +static void stbvox_bring_up_to_date(stbvox_mesh_maker *mm) +{ + if (mm->config_dirty) { + int i; + #ifdef STBVOX_ICONFIG_FACE_ATTRIBUTE + mm->num_mesh_slots = 1; + for (i=0; i < STBVOX_MAX_MESHES; ++i) { + mm->output_size[i][0] = 32; + mm->output_step[i][0] = 8; + } + #else + mm->num_mesh_slots = 2; + for (i=0; i < STBVOX_MAX_MESHES; ++i) { + mm->output_size[i][0] = 16; + mm->output_step[i][0] = 4; + mm->output_size[i][1] = 4; + mm->output_step[i][1] = 4; + } + #endif + + mm->config_dirty = 0; + } +} + +int stbvox_make_mesh(stbvox_mesh_maker *mm) +{ + int x,y; + stbvox_bring_up_to_date(mm); + mm->full = 0; + if (mm->cur_x > mm->x0 || mm->cur_y > mm->y0 || mm->cur_z > mm->z0) { + stbvox_make_mesh_for_column(mm, mm->cur_x, mm->cur_y, mm->cur_z); + if (mm->full) + return 0; + ++mm->cur_y; + while (mm->cur_y < mm->y1 && !mm->full) { + stbvox_make_mesh_for_column(mm, mm->cur_x, mm->cur_y, mm->z0); + if (mm->full) + return 0; + ++mm->cur_y; + } + ++mm->cur_x; + } + for (x=mm->cur_x; x < mm->x1; ++x) { + for (y=mm->y0; y < mm->y1; ++y) { + stbvox_make_mesh_for_column(mm, x, y, mm->z0); + if (mm->full) { + mm->cur_x = x; + mm->cur_y = y; + return 0; + } + } + } + return 1; +} + +void stbvox_init_mesh_maker(stbvox_mesh_maker *mm) +{ + memset(mm, 0, sizeof(*mm)); + stbvox_build_default_palette(); + + mm->config_dirty = 1; + mm->default_mesh = 0; +} + +int stbvox_get_buffer_count(stbvox_mesh_maker *mm) +{ + stbvox_bring_up_to_date(mm); + return mm->num_mesh_slots; +} + +int stbvox_get_buffer_size_per_quad(stbvox_mesh_maker *mm, int n) +{ + return mm->output_size[0][n]; +} + +void stbvox_reset_buffers(stbvox_mesh_maker *mm) +{ + int i; + for (i=0; i < STBVOX_MAX_MESHES*STBVOX_MAX_MESH_SLOTS; ++i) { + mm->output_cur[0][i] = 0; + mm->output_buffer[0][i] = 0; + } +} + +void stbvox_set_buffer(stbvox_mesh_maker *mm, int mesh, int slot, void *buffer, size_t len) +{ + int i; + stbvox_bring_up_to_date(mm); + mm->output_buffer[mesh][slot] = (char *) buffer; + mm->output_cur [mesh][slot] = (char *) buffer; + mm->output_len [mesh][slot] = len; + mm->output_end [mesh][slot] = (char *) buffer + len; + for (i=0; i < STBVOX_MAX_MESH_SLOTS; ++i) { + if (mm->output_buffer[mesh][i]) { + assert(mm->output_len[mesh][i] / mm->output_size[mesh][i] == mm->output_len[mesh][slot] / mm->output_size[mesh][slot]); + } + } +} + +void stbvox_set_default_mesh(stbvox_mesh_maker *mm, int mesh) +{ + mm->default_mesh = mesh; +} + +int stbvox_get_quad_count(stbvox_mesh_maker *mm, int mesh) +{ + return (mm->output_cur[mesh][0] - mm->output_buffer[mesh][0]) / mm->output_size[mesh][0]; +} + +stbvox_input_description *stbvox_get_input_description(stbvox_mesh_maker *mm) +{ + return &mm->input; +} + +void stbvox_set_input_range(stbvox_mesh_maker *mm, int x0, int y0, int z0, int x1, int y1, int z1) +{ + mm->x0 = x0; + mm->y0 = y0; + mm->z0 = z0; + + mm->x1 = x1; + mm->y1 = y1; + mm->z1 = z1; + + mm->cur_x = x0; + mm->cur_y = y0; + mm->cur_z = z0; + + // @TODO validate that this range is representable in this mode +} + +void stbvox_get_transform(stbvox_mesh_maker *mm, float transform[3][3]) +{ + // scale + transform[0][0] = 1.0; + transform[0][1] = 1.0; + #if STBVOX_CONFIG_PRECISION_Z==1 + transform[0][2] = 0.5f; + #else + transform[0][2] = 1.0f; + #endif + // translation + transform[1][0] = (float) (mm->pos_x); + transform[1][1] = (float) (mm->pos_y); + transform[1][2] = (float) (mm->pos_z); + // texture coordinate projection translation + transform[2][0] = (float) (mm->pos_x & 255); // @TODO depends on max texture scale + transform[2][1] = (float) (mm->pos_y & 255); + transform[2][2] = (float) (mm->pos_z & 255); +} + +void stbvox_get_bounds(stbvox_mesh_maker *mm, float bounds[2][3]) +{ + bounds[0][0] = (float) (mm->pos_x + mm->x0); + bounds[0][1] = (float) (mm->pos_y + mm->y0); + bounds[0][2] = (float) (mm->pos_z + mm->z0); + bounds[1][0] = (float) (mm->pos_x + mm->x1); + bounds[1][1] = (float) (mm->pos_y + mm->y1); + bounds[1][2] = (float) (mm->pos_z + mm->z1); +} + +void stbvox_set_mesh_coordinates(stbvox_mesh_maker *mm, int x, int y, int z) +{ + mm->pos_x = x; + mm->pos_y = y; + mm->pos_z = z; +} + +void stbvox_set_input_stride(stbvox_mesh_maker *mm, int x_stride_in_bytes, int y_stride_in_bytes) +{ + int f,v; + mm->x_stride_in_bytes = x_stride_in_bytes; + mm->y_stride_in_bytes = y_stride_in_bytes; + for (f=0; f < 6; ++f) { + for (v=0; v < 4; ++v) { + mm->cube_vertex_offset[f][v] = stbvox_vertex_vector[f][v][0] * mm->x_stride_in_bytes + + stbvox_vertex_vector[f][v][1] * mm->y_stride_in_bytes + + stbvox_vertex_vector[f][v][2] ; + mm->vertex_gather_offset[f][v] = (stbvox_vertex_vector[f][v][0]-1) * mm->x_stride_in_bytes + + (stbvox_vertex_vector[f][v][1]-1) * mm->y_stride_in_bytes + + (stbvox_vertex_vector[f][v][2]-1) ; + } + } +} + +///////////////////////////////////////////////////////////////////////////// +// +// offline computation of tables +// + +#if 0 +// compute optimized vheight table +static char *normal_names[32] = +{ + 0,0,0,0,"u ",0, "eu ",0, + 0,0,0,0,"ne_u",0, "nu ",0, + 0,0,0,0,"nw_u",0, "wu ",0, + 0,0,0,0,"sw_u",0, "su ",0, +}; + +static char *find_best_normal(float x, float y, float z) +{ + int best_slot = 4; + float best_dot = 0; + int i; + for (i=0; i < 32; ++i) { + if (normal_names[i]) { + float dot = x * stbvox_default_normals[i][0] + y * stbvox_default_normals[i][1] + z * stbvox_default_normals[i][2]; + if (dot > best_dot) { + best_dot = dot; + best_slot = i; + } + } + } + return normal_names[best_slot]; +} + +int main(int argc, char **argv) +{ + int sw,se,nw,ne; + for (ne=0; ne < 4; ++ne) { + for (nw=0; nw < 4; ++nw) { + for (se=0; se < 4; ++se) { + printf(" { "); + for (sw=0; sw < 4; ++sw) { + float x = (float) (nw + sw - ne - se); + float y = (float) (sw + se - nw - ne); + float z = 2; + printf("STBVF_%s, ", find_best_normal(x,y,z)); + } + printf("},\n"); + } + } + } + return 0; +} +#endif + +// @TODO +// +// - test API for texture rotation on side faces +// - API for texture rotation on top & bottom +// - better culling of vheight faces with vheight neighbors +// - better culling of non-vheight faces with vheight neighbors +// - gather vertex lighting from slopes correctly +// - better support texture edge_clamp: currently if you fall +// exactly on 1.0 you get wrapped incorrectly; this is rare, but +// can avoid: compute texcoords in vertex shader, offset towards +// center before modding, need 2 bits per vertex to know offset direction) +// - other mesh modes (10,6,4-byte quads) +// +// +// With TexBuffer for the fixed vertex data, we can actually do +// minecrafty non-blocks like stairs -- we still probably only +// want 256 or so, so we can't do the equivalent of all the vheight +// combos, but that's ok. The 256 includes baked rotations, but only +// some of them need it, and lots of block types share some faces. +// +// mode 5 (6 bytes): mode 6 (6 bytes) +// x:7 x:6 +// y:7 y:6 +// z:6 z:6 +// tex1:8 tex1:8 +// tex2:8 tex2:7 +// color:8 color:8 +// face:4 face:7 +// +// +// side faces (all x4) top&bottom faces (2x) internal faces (1x) +// 1 regular 1 regular +// 2 slabs 2 +// 8 stairs 4 stairs 16 +// 4 diag side 8 +// 4 upper diag side 8 +// 4 lower diag side 8 +// 4 crossed pairs +// +// 23*4 + 5*4 + 46 +// == 92 + 20 + 46 = 158 +// +// Must drop 30 of them to fit in 7 bits: +// ceiling half diagonals: 16+8 = 24 +// Need to get rid of 6 more. +// ceiling diagonals: 8+4 = 12 +// This brings it to 122, so can add a crossed-pair variant. +// (diagonal and non-diagonal, or randomly offset) +// Or carpet, which would be 5 more. +// +// +// Mode 4 (10 bytes): +// v: z:2,light:6 +// f: x:6,y:6,z:7, t1:8,t2:8,c:8,f:5 +// +// Mode ? (10 bytes) +// v: xyz:5 (27 values), light:3 +// f: x:7,y:7,z:6, t1:8,t2:8,c:8,f:4 +// (v: x:2,y:2,z:2,light:2) + +#endif // STB_VOXEL_RENDER_IMPLEMENTATION + +/* +------------------------------------------------------------------------------ +This software is available under 2 licenses -- choose whichever you prefer. +------------------------------------------------------------------------------ +ALTERNATIVE A - MIT License +Copyright (c) 2017 Sean Barrett +Permission is hereby granted, free of charge, to any person obtaining a copy of +this software and associated documentation files (the "Software"), to deal in +the Software without restriction, including without limitation the rights to +use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies +of the Software, and to permit persons to whom the Software is furnished to do +so, subject to the following conditions: +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +SOFTWARE. +------------------------------------------------------------------------------ +ALTERNATIVE B - Public Domain (www.unlicense.org) +This is free and unencumbered software released into the public domain. +Anyone is free to copy, modify, publish, use, compile, sell, or distribute this +software, either in source code form or as a compiled binary, for any purpose, +commercial or non-commercial, and by any means. +In jurisdictions that recognize copyright laws, the author or authors of this +software dedicate any and all copyright interest in the software to the public +domain. We make this dedication for the benefit of the public at large and to +the detriment of our heirs and successors. We intend this dedication to be an +overt act of relinquishment in perpetuity of all present and future rights to +this software under copyright law. +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN +ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION +WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. +------------------------------------------------------------------------------ +*/ |