/*
* Copyright (c) 2008-2017, NVIDIA CORPORATION.  All rights reserved.
*
* NVIDIA CORPORATION and its licensors retain all intellectual property
* and proprietary rights in and to this software, related documentation
* and any modifications thereto.  Any use, reproduction, disclosure or
* distribution of this software and related documentation without an express
* license agreement from NVIDIA CORPORATION is strictly prohibited.
*/


#include "PrimitiveRenderMesh.h"
#include "Renderer.h"


///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//											Base Mesh internal class
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

PrimitiveRenderMesh::PrimitiveRenderMesh(const float v[], UINT numVertices)
{
	std::vector<D3D11_INPUT_ELEMENT_DESC> layout;
	layout.push_back({ "POSITION", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 0, D3D11_INPUT_PER_VERTEX_DATA, 0 });
	layout.push_back({ "NORMAL", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 12, D3D11_INPUT_PER_VERTEX_DATA, 0 });

	initialize(v, numVertices, sizeof(float) * 6, layout, nullptr, 0, 0);
}


///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//													Box Mesh
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

const float boxVertices[] =
{
		-1.0f, -1.0f, -1.0f,  0.0f,  0.0f, -1.0f,
		 1.0f, -1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 
		 1.0f,  1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 
		 1.0f,  1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 
		-1.0f,  1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 
		-1.0f, -1.0f, -1.0f,  0.0f,  0.0f, -1.0f, 

		-1.0f, -1.0f,  1.0f,  0.0f,  0.0f, 1.0f,
		 1.0f,  1.0f,  1.0f,  0.0f,  0.0f, 1.0f,
		 1.0f, -1.0f,  1.0f,  0.0f,  0.0f, 1.0f,
		 1.0f,  1.0f,  1.0f,  0.0f,  0.0f, 1.0f,
		-1.0f, -1.0f,  1.0f,  0.0f,  0.0f, 1.0f,
		-1.0f,  1.0f,  1.0f,  0.0f,  0.0f, 1.0f,

		-1.0f,  1.0f,  1.0f, -1.0f,  0.0f,  0.0f,
		-1.0f, -1.0f, -1.0f, -1.0f,  0.0f,  0.0f,
		-1.0f,  1.0f, -1.0f, -1.0f,  0.0f,  0.0f,
		-1.0f, -1.0f, -1.0f, -1.0f,  0.0f,  0.0f,
		-1.0f,  1.0f,  1.0f, -1.0f,  0.0f,  0.0f,
		-1.0f, -1.0f,  1.0f, -1.0f,  0.0f,  0.0f,

		 1.0f,  1.0f,  1.0f,  1.0f,  0.0f,  0.0f,
		 1.0f,  1.0f, -1.0f,  1.0f,  0.0f,  0.0f,
		 1.0f, -1.0f, -1.0f,  1.0f,  0.0f,  0.0f,
		 1.0f, -1.0f, -1.0f,  1.0f,  0.0f,  0.0f,
		 1.0f, -1.0f,  1.0f,  1.0f,  0.0f,  0.0f,
		 1.0f,  1.0f,  1.0f,  1.0f,  0.0f,  0.0f,

		-1.0f, -1.0f, -1.0f,  0.0f, -1.0f,  0.0f,
		 1.0f, -1.0f,  1.0f,  0.0f, -1.0f,  0.0f,
		 1.0f, -1.0f, -1.0f,  0.0f, -1.0f,  0.0f,
		 1.0f, -1.0f,  1.0f,  0.0f, -1.0f,  0.0f,
		-1.0f, -1.0f, -1.0f,  0.0f, -1.0f,  0.0f,
		-1.0f, -1.0f,  1.0f,  0.0f, -1.0f,  0.0f,

		-1.0f,  1.0f, -1.0f,  0.0f,  1.0f,  0.0f,
		 1.0f,  1.0f, -1.0f,  0.0f,  1.0f,  0.0f,
		 1.0f,  1.0f,  1.0f,  0.0f,  1.0f,  0.0f,
		 1.0f,  1.0f,  1.0f,  0.0f,  1.0f,  0.0f,
		-1.0f,  1.0f,  1.0f,  0.0f,  1.0f,  0.0f,
		-1.0f,  1.0f, -1.0f,  0.0f,  1.0f,  0.0f
};

BoxRenderMesh::BoxRenderMesh() : PrimitiveRenderMesh(boxVertices, sizeof(boxVertices) / (6 * sizeof(boxVertices[0]))) {}


///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//													Plane Mesh
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

const float planeSize = 1.0f; // we use scaling instead
const float planeTilesCount = 1000.0f;

const float planeVertices[] =
{
	0,  planeSize,  planeSize, 1.0f, 0.0f, 0.0f,  planeTilesCount,  planeTilesCount,
	0,  planeSize, -planeSize, 1.0f, 0.0f, 0.0f,  planeTilesCount, -planeTilesCount,
	0, -planeSize, -planeSize, 1.0f, 0.0f, 0.0f, -planeTilesCount, -planeTilesCount,
	0, -planeSize, -planeSize, 1.0f, 0.0f, 0.0f, -planeTilesCount, -planeTilesCount,
	0, -planeSize,  planeSize, 1.0f, 0.0f, 0.0f, -planeTilesCount,  planeTilesCount,
	0,  planeSize,  planeSize, 1.0f, 0.0f, 0.0f,  planeTilesCount,  planeTilesCount
};

PlaneRenderMesh::PlaneRenderMesh()
{
	std::vector<D3D11_INPUT_ELEMENT_DESC> layout;
	layout.push_back({ "POSITION", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 0, D3D11_INPUT_PER_VERTEX_DATA, 0 });
	layout.push_back({ "NORMAL", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 12, D3D11_INPUT_PER_VERTEX_DATA, 0 });
	layout.push_back({ "TEXCOORD", 0, DXGI_FORMAT_R32G32_FLOAT, 0, 24, D3D11_INPUT_PER_VERTEX_DATA, 0 });

	initialize(planeVertices, sizeof(planeVertices) / (8 * sizeof(planeVertices[0])), sizeof(float) * 8, layout, nullptr, 0, 0);
}


///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//													Sphere Mesh
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////


const uint32_t g_numSlices = 8;  // along lines of longitude
const uint32_t g_numStacks = 16; // along lines of latitude

const uint32_t g_numSphereVertices = (g_numSlices * 2 + 1)*(g_numStacks + 1);
const uint32_t g_numSphereIndices = g_numSlices * 2 * g_numStacks * 6;

const uint32_t g_numConeVertices = (g_numSlices * 2 + 1) * 2;
const uint32_t g_numConeIndices = g_numSlices * 2 * 6;

PxVec3 g_spherePositions[g_numSphereVertices];
uint16_t g_sphereIndices[g_numSphereIndices];

void generateSphereMesh(uint16_t slices, uint16_t stacks, PxVec3* positions, uint16_t* indices)
{
	const PxF32 thetaStep = PxPi / stacks;
	const PxF32 phiStep = PxTwoPi / (slices * 2);

	PxF32 theta = 0.0f;

	// generate vertices
	for (uint16_t y = 0; y <= stacks; ++y)
	{
		PxF32 phi = 0.0f;

		PxF32 cosTheta = PxCos(theta);
		PxF32 sinTheta = PxSin(theta);

		for (uint16_t x = 0; x <= slices * 2; ++x)
		{
			PxF32 cosPhi = PxCos(phi);
			PxF32 sinPhi = PxSin(phi);

			PxVec3 p(cosPhi*sinTheta, cosTheta, sinPhi*sinTheta);

			// write vertex
			*(positions++) = p;

			phi += phiStep;
		}

		theta += thetaStep;
	}

	const uint16_t numRingQuads = 2 * slices;
	const uint16_t numRingVerts = 2 * slices + 1;

	// add faces
	for (uint16_t y = 0; y < stacks; ++y)
	{
		for (uint16_t i = 0; i < numRingQuads; ++i)
		{
			// add a quad
			*(indices++) = (y + 0)*numRingVerts + i;
			*(indices++) = (y + 1)*numRingVerts + i;
			*(indices++) = (y + 1)*numRingVerts + i + 1;

			*(indices++) = (y + 1)*numRingVerts + i + 1;
			*(indices++) = (y + 0)*numRingVerts + i + 1;
			*(indices++) = (y + 0)*numRingVerts + i;
		}
	}
}


struct SphereVertex
{
	PxVec3 position;
	PxVec3 normal;
};

SphereRenderMesh::SphereRenderMesh()
{
	generateSphereMesh(g_numSlices, g_numStacks, g_spherePositions, g_sphereIndices);

	std::vector<SphereVertex> vertices;
	for (uint32_t i = 0; i < g_numSphereVertices; i++)
	{
		vertices.push_back({ g_spherePositions[i], g_spherePositions[i] });
	}

	std::vector<D3D11_INPUT_ELEMENT_DESC> layout;
	layout.push_back({ "POSITION", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 0, D3D11_INPUT_PER_VERTEX_DATA, 0 });
	layout.push_back({ "NORMAL", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 12, D3D11_INPUT_PER_VERTEX_DATA, 0 });

	initialize(vertices.data(), (uint32_t)vertices.size(), sizeof(SphereVertex), layout, g_sphereIndices, g_numSphereIndices, 0);
}


SphereRenderMesh::~SphereRenderMesh()
{
}