/*******************************************************************************************
*
* raylib [models] example - PBR material
*
* NOTE: This example requires raylib OpenGL 3.3 for shaders support and only #version 330
* is currently supported. OpenGL ES 2.0 platforms are not supported at the moment.
*
* This example has been created using raylib 1.8 (www.raylib.com)
* raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
*
* Copyright (c) 2017 Ramon Santamaria (@raysan5)
*
********************************************************************************************/
#include "raylib.h"
#include "raymath.h"
#include "rlgl.h"
#include <stdio.h>
#define RLIGHTS_IMPLEMENTATION
#include "rlights.h"
#if defined(PLATFORM_DESKTOP)
#define GLSL_VERSION 330
#else // PLATFORM_RPI, PLATFORM_ANDROID, PLATFORM_WEB
#define GLSL_VERSION 100
#endif
#define CUBEMAP_SIZE 1024 // Cubemap texture size
#define IRRADIANCE_SIZE 32 // Irradiance texture size
#define PREFILTERED_SIZE 256 // Prefiltered HDR environment texture size
#define BRDF_SIZE 512 // BRDF LUT texture size
#define LIGHT_DISTANCE 1000.0f
#define LIGHT_HEIGHT 1.0f
// PBR texture maps generation
static TextureCubemap GenTextureCubemap(Shader shader, Texture2D panorama, int size, int format); // Generate cubemap (6 faces) from equirectangular (panorama) texture
static TextureCubemap GenTextureIrradiance(Shader shader, TextureCubemap cubemap, int size); // Generate irradiance cubemap using cubemap texture
static TextureCubemap GenTexturePrefilter(Shader shader, TextureCubemap cubemap, int size); // Generate prefilter cubemap using cubemap texture
static Texture2D GenTextureBRDF(Shader shader, int size); // Generate a generic BRDF texture
// PBR material loading
static Material LoadMaterialPBR(Color albedo, float metalness, float roughness);
int main(void)
{
// Initialization
//--------------------------------------------------------------------------------------
const int screenWidth = 800;
const int screenHeight = 450;
SetConfigFlags(FLAG_MSAA_4X_HINT); // Enable Multi Sampling Anti Aliasing 4x (if available)
InitWindow(screenWidth, screenHeight, "raylib [models] example - pbr material");
// Define the camera to look into our 3d world
Camera camera = { 0 };
camera.position = (Vector3){ 4.0f, 4.0f, 4.0f }; // Camera position
camera.target = (Vector3){ 0.0f, 0.5f, 0.0f }; // Camera looking at point
camera.up = (Vector3){ 0.0f, 1.0f, 0.0f }; // Camera up vector (rotation towards target)
camera.fovy = 45.0f; // Camera field-of-view Y
camera.projection = CAMERA_PERSPECTIVE; // Camera mode type
// Load model and PBR material
Model model = LoadModel("resources/pbr/trooper.obj");
// Mesh tangents are generated... and uploaded to GPU
// NOTE: New VBO for tangents is generated at default location and also binded to mesh VAO
//MeshTangents(&model.meshes[0]);
model.materials[0] = LoadMaterialPBR((Color){ 255, 255, 255, 255 }, 1.0f, 1.0f);
// Create lights
// NOTE: Lights are added to an internal lights pool automatically
CreateLight(LIGHT_POINT, (Vector3){ LIGHT_DISTANCE, LIGHT_HEIGHT, 0.0f }, (Vector3){ 0.0f, 0.0f, 0.0f }, (Color){ 255, 0, 0, 255 }, model.materials[0].shader);
CreateLight(LIGHT_POINT, (Vector3){ 0.0f, LIGHT_HEIGHT, LIGHT_DISTANCE }, (Vector3){ 0.0f, 0.0f, 0.0f }, (Color){ 0, 255, 0, 255 }, model.materials[0].shader);
CreateLight(LIGHT_POINT, (Vector3){ -LIGHT_DISTANCE, LIGHT_HEIGHT, 0.0f }, (Vector3){ 0.0f, 0.0f, 0.0f }, (Color){ 0, 0, 255, 255 }, model.materials[0].shader);
CreateLight(LIGHT_DIRECTIONAL, (Vector3){ 0.0f, LIGHT_HEIGHT*2.0f, -LIGHT_DISTANCE }, (Vector3){ 0.0f, 0.0f, 0.0f }, (Color){ 255, 0, 255, 255 }, model.materials[0].shader);
SetCameraMode(camera, CAMERA_ORBITAL); // Set an orbital camera mode
SetTargetFPS(60); // Set our game to run at 60 frames-per-second
//--------------------------------------------------------------------------------------
// Main game loop
while (!WindowShouldClose()) // Detect window close button or ESC key
{
// Update
//----------------------------------------------------------------------------------
UpdateCamera(&camera); // Update camera
// Send to material PBR shader camera view position
float cameraPos[3] = { camera.position.x, camera.position.y, camera.position.z };
SetShaderValue(model.materials[0].shader, model.materials[0].shader.locs[SHADER_LOC_VECTOR_VIEW], cameraPos, SHADER_UNIFORM_VEC3);
//----------------------------------------------------------------------------------
// Draw
//----------------------------------------------------------------------------------
BeginDrawing();
ClearBackground(RAYWHITE);
BeginMode3D(camera);
DrawModel(model, Vector3Zero(), 1.0f, WHITE);
DrawGrid(10, 1.0f);
EndMode3D();
DrawFPS(10, 10);
EndDrawing();
//----------------------------------------------------------------------------------
}
// De-Initialization
//--------------------------------------------------------------------------------------
UnloadMaterial(model.materials[0]); // Unload material: shader and textures
UnloadModel(model); // Unload model
CloseWindow(); // Close window and OpenGL context
//--------------------------------------------------------------------------------------
return 0;
}
// Load PBR material (Supports: ALBEDO, NORMAL, METALNESS, ROUGHNESS, AO, EMMISIVE, HEIGHT maps)
// NOTE: PBR shader is loaded inside this function
static Material LoadMaterialPBR(Color albedo, float metalness, float roughness)
{
Material mat = LoadMaterialDefault(); // Initialize material to default
// Load PBR shader (requires several maps)
mat.shader = LoadShader(TextFormat("resources/shaders/glsl%i/pbr.vs", GLSL_VERSION),
TextFormat("resources/shaders/glsl%i/pbr.fs", GLSL_VERSION));
// Get required locations points for PBR material
// NOTE: Those location names must be available and used in the shader code
mat.shader.locs[SHADER_LOC_MAP_ALBEDO] = GetShaderLocation(mat.shader, "albedo.sampler");
mat.shader.locs[SHADER_LOC_MAP_METALNESS] = GetShaderLocation(mat.shader, "metalness.sampler");
mat.shader.locs[SHADER_LOC_MAP_NORMAL] = GetShaderLocation(mat.shader, "normals.sampler");
mat.shader.locs[SHADER_LOC_MAP_ROUGHNESS] = GetShaderLocation(mat.shader, "roughness.sampler");
mat.shader.locs[SHADER_LOC_MAP_OCCLUSION] = GetShaderLocation(mat.shader, "occlusion.sampler");
//mat.shader.locs[SHADER_LOC_MAP_EMISSION] = GetShaderLocation(mat.shader, "emission.sampler");
//mat.shader.locs[SHADER_LOC_MAP_HEIGHT] = GetShaderLocation(mat.shader, "height.sampler");
mat.shader.locs[SHADER_LOC_MAP_IRRADIANCE] = GetShaderLocation(mat.shader, "irradianceMap");
mat.shader.locs[SHADER_LOC_MAP_PREFILTER] = GetShaderLocation(mat.shader, "prefilterMap");
mat.shader.locs[SHADER_LOC_MAP_BRDF] = GetShaderLocation(mat.shader, "brdfLUT");
// Set view matrix location
mat.shader.locs[SHADER_LOC_MATRIX_MODEL] = GetShaderLocation(mat.shader, "matModel");
//mat.shader.locs[SHADER_LOC_MATRIX_VIEW] = GetShaderLocation(mat.shader, "view");
mat.shader.locs[SHADER_LOC_VECTOR_VIEW] = GetShaderLocation(mat.shader, "viewPos");
// Set PBR standard maps
mat.maps[MATERIAL_MAP_ALBEDO].texture = LoadTexture("resources/pbr/trooper_albedo.png");
mat.maps[MATERIAL_MAP_NORMAL].texture = LoadTexture("resources/pbr/trooper_normals.png");
mat.maps[MATERIAL_MAP_METALNESS].texture = LoadTexture("resources/pbr/trooper_metalness.png");
mat.maps[MATERIAL_MAP_ROUGHNESS].texture = LoadTexture("resources/pbr/trooper_roughness.png");
mat.maps[MATERIAL_MAP_OCCLUSION].texture = LoadTexture("resources/pbr/trooper_ao.png");
// Set textures filtering for better quality
SetTextureFilter(mat.maps[MATERIAL_MAP_ALBEDO].texture, TEXTURE_FILTER_BILINEAR);
SetTextureFilter(mat.maps[MATERIAL_MAP_NORMAL].texture, TEXTURE_FILTER_BILINEAR);
SetTextureFilter(mat.maps[MATERIAL_MAP_METALNESS].texture, TEXTURE_FILTER_BILINEAR);
SetTextureFilter(mat.maps[MATERIAL_MAP_ROUGHNESS].texture, TEXTURE_FILTER_BILINEAR);
SetTextureFilter(mat.maps[MATERIAL_MAP_OCCLUSION].texture, TEXTURE_FILTER_BILINEAR);
// Enable sample usage in shader for assigned textures
SetShaderValue(mat.shader, GetShaderLocation(mat.shader, "albedo.useSampler"), (int[1]){ 1 }, SHADER_UNIFORM_INT);
SetShaderValue(mat.shader, GetShaderLocation(mat.shader, "normals.useSampler"), (int[1]){ 1 }, SHADER_UNIFORM_INT);
SetShaderValue(mat.shader, GetShaderLocation(mat.shader, "metalness.useSampler"), (int[1]){ 1 }, SHADER_UNIFORM_INT);
SetShaderValue(mat.shader, GetShaderLocation(mat.shader, "roughness.useSampler"), (int[1]){ 1 }, SHADER_UNIFORM_INT);
SetShaderValue(mat.shader, GetShaderLocation(mat.shader, "occlusion.useSampler"), (int[1]){ 1 }, SHADER_UNIFORM_INT);
int renderModeLoc = GetShaderLocation(mat.shader, "renderMode");
SetShaderValue(mat.shader, renderModeLoc, (int[1]){ 0 }, SHADER_UNIFORM_INT);
// Set up material properties color
mat.maps[MATERIAL_MAP_ALBEDO].color = albedo;
mat.maps[MATERIAL_MAP_NORMAL].color = (Color){ 128, 128, 255, 255 };
mat.maps[MATERIAL_MAP_METALNESS].value = metalness;
mat.maps[MATERIAL_MAP_ROUGHNESS].value = roughness;
mat.maps[MATERIAL_MAP_OCCLUSION].value = 1.0f;
mat.maps[MATERIAL_MAP_EMISSION].value = 0.5f;
mat.maps[MATERIAL_MAP_HEIGHT].value = 0.5f;
// Generate cubemap from panorama texture
//--------------------------------------------------------------------------------------------------------
Texture2D panorama = LoadTexture("resources/dresden_square_2k.hdr");
// Load equirectangular to cubemap shader
Shader shdrCubemap = LoadShader(TextFormat("resources/shaders/glsl%i/pbr.vs", GLSL_VERSION),
TextFormat("resources/shaders/glsl%i/pbr.fs", GLSL_VERSION));
SetShaderValue(shdrCubemap, GetShaderLocation(shdrCubemap, "equirectangularMap"), (int[1]){ 0 }, SHADER_UNIFORM_INT);
TextureCubemap cubemap = GenTextureCubemap(shdrCubemap, panorama, CUBEMAP_SIZE, PIXELFORMAT_UNCOMPRESSED_R32G32B32);
UnloadTexture(panorama);
UnloadShader(shdrCubemap);
//--------------------------------------------------------------------------------------------------------
// Generate irradiance map from cubemap texture
//--------------------------------------------------------------------------------------------------------
// Load irradiance (GI) calculation shader
Shader shdrIrradiance = LoadShader(TextFormat("resources/shaders/glsl%i/skybox.vs", GLSL_VERSION),
TextFormat("resources/shaders/glsl%i/irradiance.fs", GLSL_VERSION));
SetShaderValue(shdrIrradiance, GetShaderLocation(shdrIrradiance, "environmentMap"), (int[1]){ 0 }, SHADER_UNIFORM_INT);
mat.maps[MATERIAL_MAP_IRRADIANCE].texture = GenTextureIrradiance(shdrIrradiance, cubemap, IRRADIANCE_SIZE);
UnloadShader(shdrIrradiance);
//--------------------------------------------------------------------------------------------------------
// Generate prefilter map from cubemap texture
//--------------------------------------------------------------------------------------------------------
// Load reflection prefilter calculation shader
Shader shdrPrefilter = LoadShader(TextFormat("resources/shaders/glsl%i/skybox.vs", GLSL_VERSION),
TextFormat("resources/shaders/glsl%i/prefilter.fs", GLSL_VERSION));
SetShaderValue(shdrPrefilter, GetShaderLocation(shdrPrefilter, "environmentMap"), (int[1]){ 0 }, SHADER_UNIFORM_INT);
mat.maps[MATERIAL_MAP_PREFILTER].texture = GenTexturePrefilter(shdrPrefilter, cubemap, PREFILTERED_SIZE);
UnloadTexture(cubemap);
UnloadShader(shdrPrefilter);
//--------------------------------------------------------------------------------------------------------
// Generate BRDF (bidirectional reflectance distribution function) texture (using shader)
//--------------------------------------------------------------------------------------------------------
Shader shdrBRDF = LoadShader(TextFormat("resources/shaders/glsl%i/brdf.vs", GLSL_VERSION),
TextFormat("resources/shaders/glsl%i/brdf.fs", GLSL_VERSION));
mat.maps[MATERIAL_MAP_BRDF].texture = GenTextureBRDF(shdrBRDF, BRDF_SIZE);
UnloadShader(shdrBRDF);
//--------------------------------------------------------------------------------------------------------
return mat;
}
// Texture maps generation (PBR)
//-------------------------------------------------------------------------------------------
// Generate cubemap texture from HDR texture
static TextureCubemap GenTextureCubemap(Shader shader, Texture2D panorama, int size, int format)
{
TextureCubemap cubemap = { 0 };
rlDisableBackfaceCulling(); // Disable backface culling to render inside the cube
// STEP 1: Setup framebuffer
//------------------------------------------------------------------------------------------
unsigned int rbo = rlLoadTextureDepth(size, size, true);
cubemap.id = rlLoadTextureCubemap(NULL, size, format);
unsigned int fbo = rlLoadFramebuffer(size, size);
rlFramebufferAttach(fbo, rbo, RL_ATTACHMENT_DEPTH, RL_ATTACHMENT_RENDERBUFFER, 0);
rlFramebufferAttach(fbo, cubemap.id, RL_ATTACHMENT_COLOR_CHANNEL0, RL_ATTACHMENT_CUBEMAP_POSITIVE_X, 0);
// Check if framebuffer is complete with attachments (valid)
if (rlFramebufferComplete(fbo)) TraceLog(LOG_INFO, "FBO: [ID %i] Framebuffer object created successfully", fbo);
//------------------------------------------------------------------------------------------
// STEP 2: Draw to framebuffer
//------------------------------------------------------------------------------------------
// NOTE: Shader is used to convert HDR equirectangular environment map to cubemap equivalent (6 faces)
rlEnableShader(shader.id);
// Define projection matrix and send it to shader
Matrix matFboProjection = MatrixPerspective(90.0*DEG2RAD, 1.0, RL_CULL_DISTANCE_NEAR, RL_CULL_DISTANCE_FAR);
rlSetUniformMatrix(shader.locs[SHADER_LOC_MATRIX_PROJECTION], matFboProjection);
// Define view matrix for every side of the cubemap
Matrix fboViews[6] = {
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 1.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ -1.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, 1.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, 1.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, -1.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, 1.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, -1.0f }, (Vector3){ 0.0f, -1.0f, 0.0f })
};
rlViewport(0, 0, size, size); // Set viewport to current fbo dimensions
// Activate and enable texture for drawing to cubemap faces
rlActiveTextureSlot(0);
rlEnableTexture(panorama.id);
for (int i = 0; i < 6; i++)
{
// Set the view matrix for the current cube face
rlSetUniformMatrix(shader.locs[SHADER_LOC_MATRIX_VIEW], fboViews[i]);
// Select the current cubemap face attachment for the fbo
// WARNING: This function by default enables->attach->disables fbo!!!
rlFramebufferAttach(fbo, cubemap.id, RL_ATTACHMENT_COLOR_CHANNEL0, RL_ATTACHMENT_CUBEMAP_POSITIVE_X + i, 0);
rlEnableFramebuffer(fbo);
// Load and draw a cube, it uses the current enabled texture
rlClearScreenBuffers();
rlLoadDrawCube();
// ALTERNATIVE: Try to use internal batch system to draw the cube instead of rlLoadDrawCube
// for some reason this method does not work, maybe due to cube triangles definition? normals pointing out?
// TODO: Investigate this issue...
//rlSetTexture(panorama.id); // WARNING: It must be called after enabling current framebuffer if using internal batch system!
//rlClearScreenBuffers();
//DrawCubeV(Vector3Zero(), Vector3One(), WHITE);
//rlDrawRenderBatchActive();
}
//------------------------------------------------------------------------------------------
// STEP 3: Unload framebuffer and reset state
//------------------------------------------------------------------------------------------
rlDisableShader(); // Unbind shader
rlDisableTexture(); // Unbind texture
rlDisableFramebuffer(); // Unbind framebuffer
rlUnloadFramebuffer(fbo); // Unload framebuffer (and automatically attached depth texture/renderbuffer)
// Reset viewport dimensions to default
rlViewport(0, 0, rlGetFramebufferWidth(), rlGetFramebufferHeight());
rlEnableBackfaceCulling();
//------------------------------------------------------------------------------------------
cubemap.width = size;
cubemap.height = size;
cubemap.mipmaps = 1;
cubemap.format = PIXELFORMAT_UNCOMPRESSED_R32G32B32;
return cubemap;
}
// Generate irradiance texture using cubemap data
static TextureCubemap GenTextureIrradiance(Shader shader, TextureCubemap cubemap, int size)
{
TextureCubemap irradiance = { 0 };
rlDisableBackfaceCulling(); // Disable backface culling to render inside the cube
// STEP 1: Setup framebuffer
//------------------------------------------------------------------------------------------
unsigned int rbo = rlLoadTextureDepth(size, size, true);
irradiance.id = rlLoadTextureCubemap(NULL, size, PIXELFORMAT_UNCOMPRESSED_R32G32B32);
unsigned int fbo = rlLoadFramebuffer(size, size);
rlFramebufferAttach(fbo, rbo, RL_ATTACHMENT_DEPTH, RL_ATTACHMENT_RENDERBUFFER, 0);
rlFramebufferAttach(fbo, cubemap.id, RL_ATTACHMENT_COLOR_CHANNEL0, RL_ATTACHMENT_CUBEMAP_POSITIVE_X, 0);
//------------------------------------------------------------------------------------------
// STEP 2: Draw to framebuffer
//------------------------------------------------------------------------------------------
// NOTE: Shader is used to solve diffuse integral by convolution to create an irradiance cubemap
rlEnableShader(shader.id);
// Define projection matrix and send it to shader
Matrix matFboProjection = MatrixPerspective(90.0*DEG2RAD, 1.0, RL_CULL_DISTANCE_NEAR, RL_CULL_DISTANCE_FAR);
rlSetUniformMatrix(shader.locs[SHADER_LOC_MATRIX_PROJECTION], matFboProjection);
// Define view matrix for every side of the cubemap
Matrix fboViews[6] = {
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 1.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ -1.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, 1.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, 1.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, -1.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, 1.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, -1.0f }, (Vector3){ 0.0f, -1.0f, 0.0f })
};
rlActiveTextureSlot(0);
rlEnableTextureCubemap(cubemap.id);
rlViewport(0, 0, size, size); // Set viewport to current fbo dimensions
for (int i = 0; i < 6; i++)
{
rlSetUniformMatrix(shader.locs[SHADER_LOC_MATRIX_VIEW], fboViews[i]);
rlFramebufferAttach(fbo, irradiance.id, RL_ATTACHMENT_COLOR_CHANNEL0, RL_ATTACHMENT_CUBEMAP_POSITIVE_X + i, 0);
rlEnableFramebuffer(fbo);
rlClearScreenBuffers();
rlLoadDrawCube();
}
//------------------------------------------------------------------------------------------
// STEP 3: Unload framebuffer and reset state
//------------------------------------------------------------------------------------------
rlDisableShader(); // Unbind shader
rlDisableTexture(); // Unbind texture
rlDisableFramebuffer(); // Unbind framebuffer
rlUnloadFramebuffer(fbo); // Unload framebuffer (and automatically attached depth texture/renderbuffer)
// Reset viewport dimensions to default
rlViewport(0, 0, rlGetFramebufferWidth(), rlGetFramebufferHeight());
rlEnableBackfaceCulling();
//------------------------------------------------------------------------------------------
irradiance.width = size;
irradiance.height = size;
irradiance.mipmaps = 1;
irradiance.format = PIXELFORMAT_UNCOMPRESSED_R32G32B32;
return irradiance;
}
// Generate prefilter texture using cubemap data
static TextureCubemap GenTexturePrefilter(Shader shader, TextureCubemap cubemap, int size)
{
TextureCubemap prefilter = { 0 };
rlDisableBackfaceCulling(); // Disable backface culling to render inside the cube
// STEP 1: Setup framebuffer
//------------------------------------------------------------------------------------------
unsigned int rbo = rlLoadTextureDepth(size, size, true);
prefilter.id = rlLoadTextureCubemap(NULL, size, PIXELFORMAT_UNCOMPRESSED_R32G32B32);
rlTextureParameters(prefilter.id, RL_TEXTURE_MIN_FILTER, RL_TEXTURE_FILTER_MIP_LINEAR);
unsigned int fbo = rlLoadFramebuffer(size, size);
rlFramebufferAttach(fbo, rbo, RL_ATTACHMENT_DEPTH, RL_ATTACHMENT_RENDERBUFFER, 0);
rlFramebufferAttach(fbo, cubemap.id, RL_ATTACHMENT_COLOR_CHANNEL0, RL_ATTACHMENT_CUBEMAP_POSITIVE_X, 0);
//------------------------------------------------------------------------------------------
// Generate mipmaps for the prefiltered HDR texture
//glGenerateMipmap(GL_TEXTURE_CUBE_MAP); // TODO!
// STEP 2: Draw to framebuffer
//------------------------------------------------------------------------------------------
// NOTE: Shader is used to prefilter HDR and store data into mipmap levels
// Define projection matrix and send it to shader
Matrix fboProjection = MatrixPerspective(90.0*DEG2RAD, 1.0, RL_CULL_DISTANCE_NEAR, RL_CULL_DISTANCE_FAR);
rlEnableShader(shader.id);
rlSetUniformMatrix(shader.locs[SHADER_LOC_MATRIX_PROJECTION], fboProjection);
// Define view matrix for every side of the cubemap
Matrix fboViews[6] = {
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 1.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ -1.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, 1.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, 1.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, -1.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, 1.0f }, (Vector3){ 0.0f, -1.0f, 0.0f }),
MatrixLookAt((Vector3){ 0.0f, 0.0f, 0.0f }, (Vector3){ 0.0f, 0.0f, -1.0f }, (Vector3){ 0.0f, -1.0f, 0.0f })
};
rlActiveTextureSlot(0);
rlEnableTextureCubemap(cubemap.id);
// TODO: Locations should be taken out of this function... too shader dependant...
int roughnessLoc = rlGetLocationUniform(shader.id, "roughness");
rlEnableFramebuffer(fbo);
#define MAX_MIPMAP_LEVELS 5 // Max number of prefilter texture mipmaps
for (int mip = 0; mip < MAX_MIPMAP_LEVELS; mip++)
{
// Resize framebuffer according to mip-level size.
unsigned int mipWidth = size*(int)powf(0.5f, (float)mip);
unsigned int mipHeight = size*(int)powf(0.5f, (float)mip);
rlViewport(0, 0, mipWidth, mipHeight);
//glBindRenderbuffer(GL_RENDERBUFFER, rbo);
//glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT24, mipWidth, mipHeight);
float roughness = (float)mip/(float)(MAX_MIPMAP_LEVELS - 1);
rlSetUniform(roughnessLoc, &roughness, SHADER_UNIFORM_FLOAT, 1);
for (int i = 0; i < 6; i++)
{
rlSetUniformMatrix(shader.locs[SHADER_LOC_MATRIX_VIEW], fboViews[i]);
rlFramebufferAttach(fbo, prefilter.id, RL_ATTACHMENT_COLOR_CHANNEL0, RL_ATTACHMENT_CUBEMAP_POSITIVE_X + i, mip);
rlClearScreenBuffers();
rlLoadDrawCube();
}
}
//------------------------------------------------------------------------------------------
// STEP 3: Unload framebuffer and reset state
//------------------------------------------------------------------------------------------
rlDisableShader(); // Unbind shader
rlDisableTexture(); // Unbind texture
rlDisableFramebuffer(); // Unbind framebuffer
rlUnloadFramebuffer(fbo); // Unload framebuffer (and automatically attached depth texture/renderbuffer)
// Reset viewport dimensions to default
rlViewport(0, 0, rlGetFramebufferWidth(), rlGetFramebufferHeight());
rlEnableBackfaceCulling();
//------------------------------------------------------------------------------------------
prefilter.width = size;
prefilter.height = size;
prefilter.mipmaps = MAX_MIPMAP_LEVELS;
prefilter.format = PIXELFORMAT_UNCOMPRESSED_R32G32B32;
return prefilter;
}
// Generate BRDF texture using cubemap data
// TODO: Review implementation: https://github.com/HectorMF/BRDFGenerator
static Texture2D GenTextureBRDF(Shader shader, int size)
{
Texture2D brdf = { 0 };
// STEP 1: Setup framebuffer
//------------------------------------------------------------------------------------------
unsigned int rbo = rlLoadTextureDepth(size, size, true);
brdf.id = rlLoadTexture(NULL, size, size, PIXELFORMAT_UNCOMPRESSED_R32G32B32, 1);
unsigned int fbo = rlLoadFramebuffer(size, size);
rlFramebufferAttach(fbo, rbo, RL_ATTACHMENT_DEPTH, RL_ATTACHMENT_RENDERBUFFER, 0);
rlFramebufferAttach(fbo, brdf.id, RL_ATTACHMENT_COLOR_CHANNEL0, RL_ATTACHMENT_TEXTURE2D, 0);
//------------------------------------------------------------------------------------------
// STEP 2: Draw to framebuffer
//------------------------------------------------------------------------------------------
// NOTE: Render BRDF LUT into a quad using FBO
rlEnableShader(shader.id);
rlViewport(0, 0, size, size);
rlEnableFramebuffer(fbo);
rlClearScreenBuffers();
rlLoadDrawQuad();
//------------------------------------------------------------------------------------------
// STEP 3: Unload framebuffer and reset state
//------------------------------------------------------------------------------------------
rlDisableShader(); // Unbind shader
rlDisableTexture(); // Unbind texture
rlDisableFramebuffer(); // Unbind framebuffer
rlUnloadFramebuffer(fbo); // Unload framebuffer (and automatically attached depth texture/renderbuffer)
// Reset viewport dimensions to default
rlViewport(0, 0, rlGetFramebufferWidth(), rlGetFramebufferHeight());
//------------------------------------------------------------------------------------------
brdf.width = size;
brdf.height = size;
brdf.mipmaps = 1;
brdf.format = PIXELFORMAT_UNCOMPRESSED_R32G32B32;
return brdf;
}