int main()
{
// glfw: initialize and configure
// ------------------------------
glfwInit();
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_SAMPLES, 4);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
//glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE); // uncomment this statement to fix compilation on OS X
// glfw window creation
// --------------------
GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL", NULL, NULL);
glfwMakeContextCurrent(window);
if (window == NULL)
{
std::cout << "Failed to create GLFW window" << std::endl;
glfwTerminate();
return -1;
}
glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
glfwSetCursorPosCallback(window, mouse_callback);
glfwSetScrollCallback(window, scroll_callback);
// tell GLFW to capture our mouse
glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
// glad: load all OpenGL function pointers
// ---------------------------------------
if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress))
{
std::cout << "Failed to initialize GLAD" << std::endl;
return -1;
}
// configure global opengl state
// -----------------------------
glEnable(GL_DEPTH_TEST);
// set depth function to less than AND equal for skybox depth trick.
glDepthFunc(GL_LEQUAL);
// enable seamless cubemap sampling for lower mip levels in the pre-filter map.
glEnable(GL_TEXTURE_CUBE_MAP_SEAMLESS);
// build and compile shaders
// -------------------------
Shader pbrShader("2.2.2.pbr.vs", "2.2.2.pbr.fs");
Shader equirectangularToCubemapShader("2.2.2.cubemap.vs", "2.2.2.equirectangular_to_cubemap.fs");
Shader irradianceShader("2.2.2.cubemap.vs", "2.2.2.irradiance_convolution.fs");
Shader prefilterShader("2.2.2.cubemap.vs", "2.2.2.prefilter.fs");
Shader brdfShader("2.2.2.brdf.vs", "2.2.2.brdf.fs");
Shader backgroundShader("2.2.2.background.vs", "2.2.2.background.fs");
pbrShader.use();
pbrShader.setInt("irradianceMap", 0);
pbrShader.setInt("prefilterMap", 1);
pbrShader.setInt("brdfLUT", 2);
pbrShader.setInt("albedoMap", 3);
pbrShader.setInt("normalMap", 4);
pbrShader.setInt("metallicMap", 5);
pbrShader.setInt("roughnessMap", 6);
pbrShader.setInt("aoMap", 7);
backgroundShader.use();
backgroundShader.setInt("environmentMap", 0);
// load PBR material textures
// --------------------------
// rusted iron
unsigned int ironAlbedoMap = loadTexture(FileSystem::getPath("resources/textures/pbr/rusted_iron/albedo.png").c_str());
unsigned int ironNormalMap = loadTexture(FileSystem::getPath("resources/textures/pbr/rusted_iron/normal.png").c_str());
unsigned int ironMetallicMap = loadTexture(FileSystem::getPath("resources/textures/pbr/rusted_iron/metallic.png").c_str());
unsigned int ironRoughnessMap = loadTexture(FileSystem::getPath("resources/textures/pbr/rusted_iron/roughness.png").c_str());
unsigned int ironAOMap = loadTexture(FileSystem::getPath("resources/textures/pbr/rusted_iron/ao.png").c_str());
// gold
unsigned int goldAlbedoMap = loadTexture(FileSystem::getPath("resources/textures/pbr/gold/albedo.png").c_str());
unsigned int goldNormalMap = loadTexture(FileSystem::getPath("resources/textures/pbr/gold/normal.png").c_str());
unsigned int goldMetallicMap = loadTexture(FileSystem::getPath("resources/textures/pbr/gold/metallic.png").c_str());
unsigned int goldRoughnessMap = loadTexture(FileSystem::getPath("resources/textures/pbr/gold/roughness.png").c_str());
unsigned int goldAOMap = loadTexture(FileSystem::getPath("resources/textures/pbr/gold/ao.png").c_str());
// grass
unsigned int grassAlbedoMap = loadTexture(FileSystem::getPath("resources/textures/pbr/grass/albedo.png").c_str());
unsigned int grassNormalMap = loadTexture(FileSystem::getPath("resources/textures/pbr/grass/normal.png").c_str());
unsigned int grassMetallicMap = loadTexture(FileSystem::getPath("resources/textures/pbr/grass/metallic.png").c_str());
unsigned int grassRoughnessMap = loadTexture(FileSystem::getPath("resources/textures/pbr/grass/roughness.png").c_str());
unsigned int grassAOMap = loadTexture(FileSystem::getPath("resources/textures/pbr/grass/ao.png").c_str());
// plastic
unsigned int plasticAlbedoMap = loadTexture(FileSystem::getPath("resources/textures/pbr/plastic/albedo.png").c_str());
unsigned int plasticNormalMap = loadTexture(FileSystem::getPath("resources/textures/pbr/plastic/normal.png").c_str());
unsigned int plasticMetallicMap = loadTexture(FileSystem::getPath("resources/textures/pbr/plastic/metallic.png").c_str());
unsigned int plasticRoughnessMap = loadTexture(FileSystem::getPath("resources/textures/pbr/plastic/roughness.png").c_str());
unsigned int plasticAOMap = loadTexture(FileSystem::getPath("resources/textures/pbr/plastic/ao.png").c_str());
// wall
unsigned int wallAlbedoMap = loadTexture(FileSystem::getPath("resources/textures/pbr/wall/albedo.png").c_str());
unsigned int wallNormalMap = loadTexture(FileSystem::getPath("resources/textures/pbr/wall/normal.png").c_str());
unsigned int wallMetallicMap = loadTexture(FileSystem::getPath("resources/textures/pbr/wall/metallic.png").c_str());
unsigned int wallRoughnessMap = loadTexture(FileSystem::getPath("resources/textures/pbr/wall/roughness.png").c_str());
unsigned int wallAOMap = loadTexture(FileSystem::getPath("resources/textures/pbr/wall/ao.png").c_str());
// lights
// ------
glm::vec3 lightPositions[] = {
glm::vec3(-10.0f, 10.0f, 10.0f),
glm::vec3( 10.0f, 10.0f, 10.0f),
glm::vec3(-10.0f, -10.0f, 10.0f),
glm::vec3( 10.0f, -10.0f, 10.0f),
};
glm::vec3 lightColors[] = {
glm::vec3(300.0f, 300.0f, 300.0f),
glm::vec3(300.0f, 300.0f, 300.0f),
glm::vec3(300.0f, 300.0f, 300.0f),
glm::vec3(300.0f, 300.0f, 300.0f)
};
int nrRows = 7;
int nrColumns = 7;
float spacing = 2.5;
// pbr: setup framebuffer
// ----------------------
unsigned int captureFBO;
unsigned int captureRBO;
glGenFramebuffers(1, &captureFBO);
glGenRenderbuffers(1, &captureRBO);
glBindFramebuffer(GL_FRAMEBUFFER, captureFBO);
glBindRenderbuffer(GL_RENDERBUFFER, captureRBO);
glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT24, 512, 512);
glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, captureRBO);
// pbr: load the HDR environment map
// ---------------------------------
stbi_set_flip_vertically_on_load(true);
int width, height, nrComponents;
float *data = stbi_loadf(FileSystem::getPath("resources/textures/hdr/newport_loft.hdr").c_str(), &width, &height, &nrComponents, 0);
unsigned int hdrTexture;
if (data)
{
glGenTextures(1, &hdrTexture);
glBindTexture(GL_TEXTURE_2D, hdrTexture);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB16F, width, height, 0, GL_RGB, GL_FLOAT, data); // note how we specify the texture's data value to be float
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
stbi_image_free(data);
}
else
{
std::cout << "Failed to load HDR image." << std::endl;
}
// pbr: setup cubemap to render to and attach to framebuffer
// ---------------------------------------------------------
unsigned int envCubemap;
glGenTextures(1, &envCubemap);
glBindTexture(GL_TEXTURE_CUBE_MAP, envCubemap);
for (unsigned int i = 0; i < 6; ++i)
{
glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, GL_RGB16F, 512, 512, 0, GL_RGB, GL_FLOAT, nullptr);
}
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR); // enable pre-filter mipmap sampling (combatting visible dots artifact)
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// pbr: set up projection and view matrices for capturing data onto the 6 cubemap face directions
// ----------------------------------------------------------------------------------------------
glm::mat4 captureProjection = glm::perspective(glm::radians(90.0f), 1.0f, 0.1f, 10.0f);
glm::mat4 captureViews[] =
{
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3( 1.0f, 0.0f, 0.0f), glm::vec3(0.0f, -1.0f, 0.0f)),
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(-1.0f, 0.0f, 0.0f), glm::vec3(0.0f, -1.0f, 0.0f)),
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3( 0.0f, 1.0f, 0.0f), glm::vec3(0.0f, 0.0f, 1.0f)),
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3( 0.0f, -1.0f, 0.0f), glm::vec3(0.0f, 0.0f, -1.0f)),
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3( 0.0f, 0.0f, 1.0f), glm::vec3(0.0f, -1.0f, 0.0f)),
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3( 0.0f, 0.0f, -1.0f), glm::vec3(0.0f, -1.0f, 0.0f))
};
// pbr: convert HDR equirectangular environment map to cubemap equivalent
// ----------------------------------------------------------------------
equirectangularToCubemapShader.use();
equirectangularToCubemapShader.setInt("equirectangularMap", 0);
equirectangularToCubemapShader.setMat4("projection", captureProjection);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, hdrTexture);
glViewport(0, 0, 512, 512); // don't forget to configure the viewport to the capture dimensions.
glBindFramebuffer(GL_FRAMEBUFFER, captureFBO);
for (unsigned int i = 0; i < 6; ++i)
{
equirectangularToCubemapShader.setMat4("view", captureViews[i]);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, envCubemap, 0);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
renderCube();
}
glBindFramebuffer(GL_FRAMEBUFFER, 0);
// then let OpenGL generate mipmaps from first mip face (combatting visible dots artifact)
glBindTexture(GL_TEXTURE_CUBE_MAP, envCubemap);
glGenerateMipmap(GL_TEXTURE_CUBE_MAP);
// pbr: create an irradiance cubemap, and re-scale capture FBO to irradiance scale.
// --------------------------------------------------------------------------------
unsigned int irradianceMap;
glGenTextures(1, &irradianceMap);
glBindTexture(GL_TEXTURE_CUBE_MAP, irradianceMap);
for (unsigned int i = 0; i < 6; ++i)
{
glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, GL_RGB16F, 32, 32, 0, GL_RGB, GL_FLOAT, nullptr);
}
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glBindFramebuffer(GL_FRAMEBUFFER, captureFBO);
glBindRenderbuffer(GL_RENDERBUFFER, captureRBO);
glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT24, 32, 32);
// pbr: solve diffuse integral by convolution to create an irradiance (cube)map.
// -----------------------------------------------------------------------------
irradianceShader.use();
irradianceShader.setInt("environmentMap", 0);
irradianceShader.setMat4("projection", captureProjection);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_CUBE_MAP, envCubemap);
glViewport(0, 0, 32, 32); // don't forget to configure the viewport to the capture dimensions.
glBindFramebuffer(GL_FRAMEBUFFER, captureFBO);
for (unsigned int i = 0; i < 6; ++i)
{
irradianceShader.setMat4("view", captureViews[i]);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, irradianceMap, 0);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
renderCube();
}
glBindFramebuffer(GL_FRAMEBUFFER, 0);
// pbr: create a pre-filter cubemap, and re-scale capture FBO to pre-filter scale.
// --------------------------------------------------------------------------------
unsigned int prefilterMap;
glGenTextures(1, &prefilterMap);
glBindTexture(GL_TEXTURE_CUBE_MAP, prefilterMap);
for (unsigned int i = 0; i < 6; ++i)
{
glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, GL_RGB16F, 128, 128, 0, GL_RGB, GL_FLOAT, nullptr);
}
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR); // be sure to set minifcation filter to mip_linear
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// generate mipmaps for the cubemap so OpenGL automatically allocates the required memory.
glGenerateMipmap(GL_TEXTURE_CUBE_MAP);
// pbr: run a quasi monte-carlo simulation on the environment lighting to create a prefilter (cube)map.
// ----------------------------------------------------------------------------------------------------
prefilterShader.use();
prefilterShader.setInt("environmentMap", 0);
prefilterShader.setMat4("projection", captureProjection);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_CUBE_MAP, envCubemap);
glBindFramebuffer(GL_FRAMEBUFFER, captureFBO);
unsigned int maxMipLevels = 5;
for (unsigned int mip = 0; mip < maxMipLevels; ++mip)
{
// reisze framebuffer according to mip-level size.
unsigned int mipWidth = 128 * std::pow(0.5, mip);
unsigned int mipHeight = 128 * std::pow(0.5, mip);
glBindRenderbuffer(GL_RENDERBUFFER, captureRBO);
glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT24, mipWidth, mipHeight);
glViewport(0, 0, mipWidth, mipHeight);
float roughness = (float)mip / (float)(maxMipLevels - 1);
prefilterShader.setFloat("roughness", roughness);
for (unsigned int i = 0; i < 6; ++i)
{
prefilterShader.setMat4("view", captureViews[i]);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, prefilterMap, mip);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
renderCube();
}
}
glBindFramebuffer(GL_FRAMEBUFFER, 0);
// pbr: generate a 2D LUT from the BRDF equations used.
// ----------------------------------------------------
unsigned int brdfLUTTexture;
glGenTextures(1, &brdfLUTTexture);
// pre-allocate enough memory for the LUT texture.
glBindTexture(GL_TEXTURE_2D, brdfLUTTexture);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RG16F, 512, 512, 0, GL_RG, GL_FLOAT, 0);
// be sure to set wrapping mode to GL_CLAMP_TO_EDGE
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// then re-configure capture framebuffer object and render screen-space quad with BRDF shader.
glBindFramebuffer(GL_FRAMEBUFFER, captureFBO);
glBindRenderbuffer(GL_RENDERBUFFER, captureRBO);
glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT24, 512, 512);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, brdfLUTTexture, 0);
glViewport(0, 0, 512, 512);
brdfShader.use();
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
renderQuad();
glBindFramebuffer(GL_FRAMEBUFFER, 0);
// initialize static shader uniforms before rendering
// --------------------------------------------------
glm::mat4 projection = glm::perspective(camera.Zoom, (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f);
pbrShader.use();
pbrShader.setMat4("projection", projection);
backgroundShader.use();
backgroundShader.setMat4("projection", projection);
// then before rendering, configure the viewport to the original framebuffer's screen dimensions
int scrWidth, scrHeight;
glfwGetFramebufferSize(window, &scrWidth, &scrHeight);
glViewport(0, 0, scrWidth, scrHeight);
// render loop
// -----------
while (!glfwWindowShouldClose(window))
{
// per-frame time logic
// --------------------
float currentFrame = glfwGetTime();
deltaTime = currentFrame - lastFrame;
lastFrame = currentFrame;
// input
// -----
processInput(window);
// render
// ------
glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// render scene, supplying the convoluted irradiance map to the final shader.
// ------------------------------------------------------------------------------------------
pbrShader.use();
glm::mat4 model;
glm::mat4 view = camera.GetViewMatrix();
pbrShader.setMat4("view", view);
pbrShader.setVec3("camPos", camera.Position);
// bind pre-computed IBL data
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_CUBE_MAP, irradianceMap);
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_CUBE_MAP, prefilterMap);
glActiveTexture(GL_TEXTURE2);
glBindTexture(GL_TEXTURE_2D, brdfLUTTexture);
// rusted iron
glActiveTexture(GL_TEXTURE3);
glBindTexture(GL_TEXTURE_2D, ironAlbedoMap);
glActiveTexture(GL_TEXTURE4);
glBindTexture(GL_TEXTURE_2D, ironNormalMap);
glActiveTexture(GL_TEXTURE5);
glBindTexture(GL_TEXTURE_2D, ironMetallicMap);
glActiveTexture(GL_TEXTURE6);
glBindTexture(GL_TEXTURE_2D, ironRoughnessMap);
glActiveTexture(GL_TEXTURE7);
glBindTexture(GL_TEXTURE_2D, ironAOMap);
model = glm::mat4();
model = glm::translate(model, glm::vec3(-5.0, 0.0, 2.0));
pbrShader.setMat4("model", model);
renderSphere();
// gold
glActiveTexture(GL_TEXTURE3);
glBindTexture(GL_TEXTURE_2D, goldAlbedoMap);
glActiveTexture(GL_TEXTURE4);
glBindTexture(GL_TEXTURE_2D, goldNormalMap);
glActiveTexture(GL_TEXTURE5);
glBindTexture(GL_TEXTURE_2D, goldMetallicMap);
glActiveTexture(GL_TEXTURE6);
glBindTexture(GL_TEXTURE_2D, goldRoughnessMap);
glActiveTexture(GL_TEXTURE7);
glBindTexture(GL_TEXTURE_2D, goldAOMap);
model = glm::mat4();
model = glm::translate(model, glm::vec3(-3.0, 0.0, 2.0));
pbrShader.setMat4("model", model);
renderSphere();
// grass
glActiveTexture(GL_TEXTURE3);
glBindTexture(GL_TEXTURE_2D, grassAlbedoMap);
glActiveTexture(GL_TEXTURE4);
glBindTexture(GL_TEXTURE_2D, grassNormalMap);
glActiveTexture(GL_TEXTURE5);
glBindTexture(GL_TEXTURE_2D, grassMetallicMap);
glActiveTexture(GL_TEXTURE6);
glBindTexture(GL_TEXTURE_2D, grassRoughnessMap);
glActiveTexture(GL_TEXTURE7);
glBindTexture(GL_TEXTURE_2D, grassAOMap);
model = glm::mat4();
model = glm::translate(model, glm::vec3(-1.0, 0.0, 2.0));
pbrShader.setMat4("model", model);
renderSphere();
// plastic
glActiveTexture(GL_TEXTURE3);
glBindTexture(GL_TEXTURE_2D, plasticAlbedoMap);
glActiveTexture(GL_TEXTURE4);
glBindTexture(GL_TEXTURE_2D, plasticNormalMap);
glActiveTexture(GL_TEXTURE5);
glBindTexture(GL_TEXTURE_2D, plasticMetallicMap);
glActiveTexture(GL_TEXTURE6);
glBindTexture(GL_TEXTURE_2D, plasticRoughnessMap);
glActiveTexture(GL_TEXTURE7);
glBindTexture(GL_TEXTURE_2D, plasticAOMap);
model = glm::mat4();
model = glm::translate(model, glm::vec3(1.0, 0.0, 2.0));
pbrShader.setMat4("model", model);
renderSphere();
// wall
glActiveTexture(GL_TEXTURE3);
glBindTexture(GL_TEXTURE_2D, wallAlbedoMap);
glActiveTexture(GL_TEXTURE4);
glBindTexture(GL_TEXTURE_2D, wallNormalMap);
glActiveTexture(GL_TEXTURE5);
glBindTexture(GL_TEXTURE_2D, wallMetallicMap);
glActiveTexture(GL_TEXTURE6);
glBindTexture(GL_TEXTURE_2D, wallRoughnessMap);
glActiveTexture(GL_TEXTURE7);
glBindTexture(GL_TEXTURE_2D, wallAOMap);
model = glm::mat4();
model = glm::translate(model, glm::vec3(3.0, 0.0, 2.0));
pbrShader.setMat4("model", model);
renderSphere();
// render light source (simply re-render sphere at light positions)
// this looks a bit off as we use the same shader, but it'll make their positions obvious and
// keeps the codeprint small.
for (unsigned int i = 0; i < sizeof(lightPositions) / sizeof(lightPositions[0]); ++i)
{
glm::vec3 newPos = lightPositions[i] + glm::vec3(sin(glfwGetTime() * 5.0) * 5.0, 0.0, 0.0);
newPos = lightPositions[i];
pbrShader.setVec3("lightPositions[" + std::to_string(i) + "]", newPos);
pbrShader.setVec3("lightColors[" + std::to_string(i) + "]", lightColors[i]);
model = glm::mat4();
model = glm::translate(model, newPos);
model = glm::scale(model, glm::vec3(0.5f));
pbrShader.setMat4("model", model);
renderSphere();
}
// render skybox (render as last to prevent overdraw)
backgroundShader.use();
backgroundShader.setMat4("view", view);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_CUBE_MAP, envCubemap);
//glBindTexture(GL_TEXTURE_CUBE_MAP, irradianceMap); // display irradiance map
//glBindTexture(GL_TEXTURE_CUBE_MAP, prefilterMap); // display prefilter map
renderCube();
// render BRDF map to screen
//brdfShader.Use();
//renderQuad();
// glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.)
// -------------------------------------------------------------------------------
glfwSwapBuffers(window);
glfwPollEvents();
}
// glfw: terminate, clearing all previously allocated GLFW resources.
// ------------------------------------------------------------------
glfwTerminate();
return 0;
}
int main()
{
// glfw: initialize and configure
// ------------------------------
glfwInit();
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_SAMPLES, 4);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
// glfw window creation
// --------------------
GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL", NULL, NULL);
glfwMakeContextCurrent(window);
if (window == NULL)
{
std::cout << "Failed to create GLFW window" << std::endl;
glfwTerminate();
return -1;
}
glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
glfwSetCursorPosCallback(window, mouse_callback);
glfwSetScrollCallback(window, scroll_callback);
// tell GLFW to capture our mouse
glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
// glad: load all OpenGL function pointers
// ---------------------------------------
if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress))
{
std::cout << "Failed to initialize GLAD" << std::endl;
return -1;
}
// configure global opengl state
// -----------------------------
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LEQUAL); // set depth function to less than AND equal for skybox depth trick.
// build and compile shaders
// -------------------------
Shader pbrShader("2.1.2.pbr.vs", "2.1.2.pbr.fs");
Shader equirectangularToCubemapShader("2.1.2.cubemap.vs", "2.1.2.equirectangular_to_cubemap.fs");
Shader irradianceShader("2.1.2.cubemap.vs", "2.1.2.irradiance_convolution.fs");
Shader backgroundShader("2.1.2.background.vs", "2.1.2.background.fs");
pbrShader.use();
pbrShader.setInt("irradianceMap", 0);
pbrShader.setVec3("albedo", 0.5f, 0.0f, 0.0f);
pbrShader.setFloat("ao", 1.0f);
backgroundShader.use();
backgroundShader.setInt("environmentMap", 0);
// lights
// ------
glm::vec3 lightPositions[] = {
glm::vec3(-10.0f, 10.0f, 10.0f),
glm::vec3( 10.0f, 10.0f, 10.0f),
glm::vec3(-10.0f, -10.0f, 10.0f),
glm::vec3( 10.0f, -10.0f, 10.0f),
};
glm::vec3 lightColors[] = {
glm::vec3(300.0f, 300.0f, 300.0f),
glm::vec3(300.0f, 300.0f, 300.0f),
glm::vec3(300.0f, 300.0f, 300.0f),
glm::vec3(300.0f, 300.0f, 300.0f)
};
int nrRows = 7;
int nrColumns = 7;
float spacing = 2.5;
// pbr: setup framebuffer
// ----------------------
unsigned int captureFBO;
unsigned int captureRBO;
glGenFramebuffers(1, &captureFBO);
glGenRenderbuffers(1, &captureRBO);
glBindFramebuffer(GL_FRAMEBUFFER, captureFBO);
glBindRenderbuffer(GL_RENDERBUFFER, captureRBO);
glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT24, 512, 512);
glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, captureRBO);
// pbr: load the HDR environment map
// ---------------------------------
stbi_set_flip_vertically_on_load(true);
int width, height, nrComponents;
float *data = stbi_loadf(FileSystem::getPath("resources/textures/hdr/newport_loft.hdr").c_str(), &width, &height, &nrComponents, 0);
unsigned int hdrTexture;
if (data)
{
glGenTextures(1, &hdrTexture);
glBindTexture(GL_TEXTURE_2D, hdrTexture);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB16F, width, height, 0, GL_RGB, GL_FLOAT, data); // note how we specify the texture's data value to be float
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
stbi_image_free(data);
}
else
{
std::cout << "Failed to load HDR image." << std::endl;
}
// pbr: setup cubemap to render to and attach to framebuffer
// ---------------------------------------------------------
unsigned int envCubemap;
glGenTextures(1, &envCubemap);
glBindTexture(GL_TEXTURE_CUBE_MAP, envCubemap);
for (unsigned int i = 0; i < 6; ++i)
{
glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, GL_RGB16F, 512, 512, 0, GL_RGB, GL_FLOAT, nullptr);
}
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// pbr: set up projection and view matrices for capturing data onto the 6 cubemap face directions
// ----------------------------------------------------------------------------------------------
glm::mat4 captureProjection = glm::perspective(glm::radians(90.0f), 1.0f, 0.1f, 10.0f);
glm::mat4 captureViews[] =
{
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(1.0f, 0.0f, 0.0f), glm::vec3(0.0f, -1.0f, 0.0f)),
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(-1.0f, 0.0f, 0.0f), glm::vec3(0.0f, -1.0f, 0.0f)),
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(0.0f, 1.0f, 0.0f), glm::vec3(0.0f, 0.0f, 1.0f)),
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(0.0f, -1.0f, 0.0f), glm::vec3(0.0f, 0.0f, -1.0f)),
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(0.0f, 0.0f, 1.0f), glm::vec3(0.0f, -1.0f, 0.0f)),
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(0.0f, 0.0f, -1.0f), glm::vec3(0.0f, -1.0f, 0.0f))
};
// pbr: convert HDR equirectangular environment map to cubemap equivalent
// ----------------------------------------------------------------------
equirectangularToCubemapShader.use();
equirectangularToCubemapShader.setInt("equirectangularMap", 0);
equirectangularToCubemapShader.setMat4("projection", captureProjection);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, hdrTexture);
glViewport(0, 0, 512, 512); // don't forget to configure the viewport to the capture dimensions.
glBindFramebuffer(GL_FRAMEBUFFER, captureFBO);
for (unsigned int i = 0; i < 6; ++i)
{
equirectangularToCubemapShader.setMat4("view", captureViews[i]);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, envCubemap, 0);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
renderCube();
}
glBindFramebuffer(GL_FRAMEBUFFER, 0);
// pbr: create an irradiance cubemap, and re-scale capture FBO to irradiance scale.
// --------------------------------------------------------------------------------
unsigned int irradianceMap;
glGenTextures(1, &irradianceMap);
glBindTexture(GL_TEXTURE_CUBE_MAP, irradianceMap);
for (unsigned int i = 0; i < 6; ++i)
{
glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, GL_RGB16F, 32, 32, 0, GL_RGB, GL_FLOAT, nullptr);
}
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glBindFramebuffer(GL_FRAMEBUFFER, captureFBO);
glBindRenderbuffer(GL_RENDERBUFFER, captureRBO);
glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT24, 32, 32);
// pbr: solve diffuse integral by convolution to create an irradiance (cube)map.
// -----------------------------------------------------------------------------
irradianceShader.use();
irradianceShader.setInt("environmentMap", 0);
irradianceShader.setMat4("projection", captureProjection);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_CUBE_MAP, envCubemap);
glViewport(0, 0, 32, 32); // don't forget to configure the viewport to the capture dimensions.
glBindFramebuffer(GL_FRAMEBUFFER, captureFBO);
for (unsigned int i = 0; i < 6; ++i)
{
irradianceShader.setMat4("view", captureViews[i]);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, irradianceMap, 0);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
renderCube();
}
glBindFramebuffer(GL_FRAMEBUFFER, 0);
// initialize static shader uniforms before rendering
// --------------------------------------------------
glm::mat4 projection = glm::perspective(camera.Zoom, (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f);
pbrShader.use();
pbrShader.setMat4("projection", projection);
backgroundShader.use();
backgroundShader.setMat4("projection", projection);
// then before rendering, configure the viewport to the original framebuffer's screen dimensions
int scrWidth, scrHeight;
glfwGetFramebufferSize(window, &scrWidth, &scrHeight);
glViewport(0, 0, scrWidth, scrHeight);
// render loop
// -----------
while (!glfwWindowShouldClose(window))
{
// per-frame time logic
// --------------------
float currentFrame = glfwGetTime();
deltaTime = currentFrame - lastFrame;
lastFrame = currentFrame;
// input
// -----
processInput(window);
// render
// ------
glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// render scene, supplying the convoluted irradiance map to the final shader.
// ------------------------------------------------------------------------------------------
pbrShader.use();
glm::mat4 view = camera.GetViewMatrix();
pbrShader.setMat4("view", view);
pbrShader.setVec3("camPos", camera.Position);
// bind pre-computed IBL data
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_CUBE_MAP, irradianceMap);
// render rows*column number of spheres with material properties defined by textures (they all have the same material properties)
glm::mat4 model;
for (int row = 0; row < nrRows; ++row)
{
pbrShader.setFloat("metallic", (float)row / (float)nrRows);
for (int col = 0; col < nrColumns; ++col)
{
// we clamp the roughness to 0.025 - 1.0 as perfectly smooth surfaces (roughness of 0.0) tend to look a bit off
// on direct lighting.
pbrShader.setFloat("roughness", glm::clamp((float)col / (float)nrColumns, 0.05f, 1.0f));
model = glm::mat4();
model = glm::translate(model, glm::vec3(
(float)(col - (nrColumns / 2)) * spacing,
(float)(row - (nrRows / 2)) * spacing,
-2.0f
));
pbrShader.setMat4("model", model);
renderSphere();
}
}
// render light source (simply re-render sphere at light positions)
// this looks a bit off as we use the same shader, but it'll make their positions obvious and
// keeps the codeprint small.
for (unsigned int i = 0; i < sizeof(lightPositions) / sizeof(lightPositions[0]); ++i)
{
glm::vec3 newPos = lightPositions[i] + glm::vec3(sin(glfwGetTime() * 5.0) * 5.0, 0.0, 0.0);
newPos = lightPositions[i];
pbrShader.setVec3("lightPositions[" + std::to_string(i) + "]", newPos);
pbrShader.setVec3("lightColors[" + std::to_string(i) + "]", lightColors[i]);
model = glm::mat4();
model = glm::translate(model, newPos);
model = glm::scale(model, glm::vec3(0.5f));
pbrShader.setMat4("model", model);
renderSphere();
}
// render skybox (render as last to prevent overdraw)
backgroundShader.use();
backgroundShader.setMat4("view", view);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_CUBE_MAP, envCubemap);
//glBindTexture(GL_TEXTURE_CUBE_MAP, irradianceMap); // display irradiance map
renderCube();
// glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.)
// -------------------------------------------------------------------------------
glfwSwapBuffers(window);
glfwPollEvents();
}
// glfw: terminate, clearing all previously allocated GLFW resources.
// ------------------------------------------------------------------
glfwTerminate();
return 0;
}