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Diffstat (limited to 'materialsystem/stdshaders/ParticleSphere.vsh')
| -rw-r--r-- | materialsystem/stdshaders/ParticleSphere.vsh | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/materialsystem/stdshaders/ParticleSphere.vsh b/materialsystem/stdshaders/ParticleSphere.vsh new file mode 100644 index 0000000..b2d8384 --- /dev/null +++ b/materialsystem/stdshaders/ParticleSphere.vsh @@ -0,0 +1,163 @@ +vs.1.1 + +# DYNAMIC: "DOWATERFOG" "0..1" + +#include "macros.vsh" + +$cQuarter = "c91.x"; + +;------------------------------------------------------------------------------ +; Constants specified by the app +; c0 = (0, 1, 2, 0.5) +; c1 = (1/2.2, 0, 0, 0) +; 2 = camera position *in world space* +; c4-c7 = modelViewProj matrix (transpose) +; c8-c11 = ViewProj matrix (transpose) +; c12-c15 = model->world matrix (transpose) +; c16 = [fogStart, fogEnd, fogRange, undefined] +; c17-c20 = model->view matrix (transpose) +; +; The ParticleSphere lighting equation is: +; A + [N dot ||L - P||] * C * r / |L - P|^2 +; +; where: +; A = ambient light color +; N = particle normal (stored in the texture) +; L = directional light position +; P = point on surface +; C = directional light color +; r = directional light intensity +; +; This shader just does the |L - P| part and the pixel shader does the rest. +; +; Vertex components +; $vPos = Position +; $vSpecular = Directional light color +; $vColor = Ambient color (and alpha) +; $vTexCoord0 = Texture coordinates for normal map +; $vTexCoord0.z = Index into the light list for light info + + + +;------------------------------------------------------------------------------ +; Constant registers +;------------------------------------------------------------------------------ + +;------------------------------------------------------------------------------ +; Vertex blending +;------------------------------------------------------------------------------ + +&AllocateRegister( \$projPos ); + +; Transform position from object to projection space +dp4 $projPos.x, $vPos, $cModelViewProj0 +dp4 $projPos.y, $vPos, $cModelViewProj1 +dp4 $projPos.z, $vPos, $cModelViewProj2 +dp4 $projPos.w, $vPos, $cModelViewProj3 + +mov oPos, $projPos + +;------------------------------------------------------------------------------ +; Fog +;------------------------------------------------------------------------------ + +alloc $worldPos +if( $DOWATERFOG == 1 ) +{ + ; Get the worldpos z component only since that's all we need for height fog + dp4 $worldPos.z, $vPos, $cModel2 +} +&CalcFog( $worldPos, $projPos ); +free $worldPos + +&FreeRegister( \$projPos ); + +;------------------------------------------------------------------------------ +; Setup to index our directional light. +;------------------------------------------------------------------------------ +mov a0.x, $vTexCoord0.z + + +;------------------------------------------------------------------------------ +; Copy texcoords for the normal map texture +;------------------------------------------------------------------------------ + +mov oT0, $vTexCoord0 +mov oT2.xyz, $vColor + +; FIXME : the rest of this needs to use AllocateRegister + +;------------------------------------------------------------------------------ +; Generate a tangent space and rotate L. +; This can be thought of as rotating the normal map to face the viewer. +; +; This is useful when a particle is way off to the side of the screen. +; You should be looking at the half-sphere with a normal pointing from the +; particle to the viewer. Instead, you're looking at the half-sphere with +; a normal along Z. This tangent space builder code fixes the problem. +; +; Note that since the model and view matrices are identity, the coordinate +; system has X=right, Y=up, and Z=behind you (negative Z goes into the screen). +;------------------------------------------------------------------------------ + ; r5 (forward) = normalized P +dp3 r1, $vPos, $vPos +rsq r5, r1 +mul r5, r5, $vPos +mov r5.z, -r5.z ; This basis wants Z positive going into the screen + ; so flip it here. + + ; r1 (up) = r5 x c24 +mul r1, r5.xzyw, $SHADER_SPECIFIC_CONST_0; (This effectively does a cross product with [1,0,0,0] + ; You wind up with [0, r5.z, -r5.y, 1] +dp3 r2, r1, r1 +rsq r2, r2 +mul r1, r1, r2 + + ; r2 (right) = r1 x r5 +mul r2, r1.yzxw, r5.zxyw +mad r2, -r1.zxyw, r5.yzxw, r2 + +sub r3, c[45 + a0.x], $vPos ; r3 = L - P + +; transposed matrix mul +mul r0, r2, r3.xxxx ; x * right +mad r0, r1, r3.yyyy, r0 ; + y * up +mad r0, r5, r3.zzzz, r0 ; + z * forward + + +;------------------------------------------------------------------------------ +; Put ||L - P|| into t1 +;------------------------------------------------------------------------------ +dp3 r2, r0, r0 ; r2 = Length(L - P)^2 +rsq r3, r2 ; r3 = 1 / Length(L - P) +mul r8, r0, r3 ; r8 = Normalize(L - P) +mul r9, r8, $cQuarter ; r9 = Normalize(L - P) * 0.25 +add oT1, r9, c0.w ; oT1 = Normalize(L - P) * 0.25 + 0.5 + + +;------------------------------------------------------------------------------ +; Setup the diffuse light color (C * r / ||L - P||^2) +;------------------------------------------------------------------------------ + +mul r8, c[46 + a0.x], $vSpecular ; r8 = C * r +rcp r7, r2 ; r7 = 1 / Length(L - P)^2 + +; rescale the color if necessary +mul r8, r8, r7 ; r8 = C * r / Length(L - P)^2 + +; We're doing both parts of an if statement here, with each part scaled by 0 or 1. +mul r9, r7, c[46 + a0.x] ; r9 = r / Length(L - P)^2 + +; If the light intensity scales the color > 1 + sge r10, r9.xxxx, $cOne ; r10.x = 1 if the color's max component > 1 + rcp r6, r9.xxxx + mul r6, r6, r10.xxxx ; r6 = 1 / max_component or [0,0,0,0] if max_component < 1 + mul r2, r8, r6 ; rescaled color (all zeros if no component was > 1) +; else + slt r11, r9.xxxx, $cOne ; r11.x = 1 if the color's max component < 1 + mad oD0.xyz, r8, r11, r2 ; if it was rescaled, then r8*r11 = 0 + ; if not, then r8*r11 = the original color + +mov oD0.a, $vColor.a ; Pass in vertex alpha so the pixel shader can use it. + + |