#include <glad/glad.h>
#include <GLFW/glfw3.h>
#include <stb_image.h>
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtc/type_ptr.hpp>
#include <learnopengl/shader.h>
#include <learnopengl/camera.h>
#include <learnopengl/model.h>
#include <iostream>
void framebuffer_size_callback(GLFWwindow* window, int width, int height);
void mouse_callback(GLFWwindow* window, double xpos, double ypos);
void scroll_callback(GLFWwindow* window, double xoffset, double yoffset);
void processInput(GLFWwindow *window);
unsigned int loadTexture(const char *path);
void renderScene(const Shader &shader);
void renderCube();
// settings
const unsigned int SCR_WIDTH = 800;
const unsigned int SCR_HEIGHT = 600;
bool shadows = true;
bool shadowsKeyPressed = false;
// camera
Camera camera(glm::vec3(0.0f, 0.0f, 3.0f));
float lastX = (float)SCR_WIDTH / 2.0;
float lastY = (float)SCR_HEIGHT / 2.0;
bool firstMouse = true;
// timing
float deltaTime = 0.0f;
float lastFrame = 0.0f;
int main()
{
// glfw: initialize and configure
// ------------------------------
glfwInit();
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
#ifdef __APPLE__
glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
#endif
// glfw window creation
// --------------------
GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "LearnOpenGL", NULL, NULL);
if (window == NULL)
{
std::cout << "Failed to create GLFW window" << std::endl;
glfwTerminate();
return -1;
}
glfwMakeContextCurrent(window);
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);
glEnable(GL_CULL_FACE);
// build and compile shaders
// -------------------------
Shader shader("3.2.1.point_shadows.vs", "3.2.1.point_shadows.fs");
Shader simpleDepthShader("3.2.1.point_shadows_depth.vs", "3.2.1.point_shadows_depth.fs", "3.2.1.point_shadows_depth.gs");
// load textures
// -------------
unsigned int woodTexture = loadTexture(FileSystem::getPath("resources/textures/wood.png").c_str());
// configure depth map FBO
// -----------------------
const unsigned int SHADOW_WIDTH = 1024, SHADOW_HEIGHT = 1024;
unsigned int depthMapFBO;
glGenFramebuffers(1, &depthMapFBO);
// create depth cubemap texture
unsigned int depthCubemap;
glGenTextures(1, &depthCubemap);
glBindTexture(GL_TEXTURE_CUBE_MAP, depthCubemap);
for (unsigned int i = 0; i < 6; ++i)
glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, GL_DEPTH_COMPONENT, SHADOW_WIDTH, SHADOW_HEIGHT, 0, GL_DEPTH_COMPONENT, GL_FLOAT, NULL);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
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);
// attach depth texture as FBO's depth buffer
glBindFramebuffer(GL_FRAMEBUFFER, depthMapFBO);
glFramebufferTexture(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, depthCubemap, 0);
glDrawBuffer(GL_NONE);
glReadBuffer(GL_NONE);
glBindFramebuffer(GL_FRAMEBUFFER, 0);
// shader configuration
// --------------------
shader.use();
shader.setInt("diffuseTexture", 0);
shader.setInt("depthMap", 1);
// lighting info
// -------------
glm::vec3 lightPos(0.0f, 0.0f, 0.0f);
// render loop
// -----------
while (!glfwWindowShouldClose(window))
{
// per-frame time logic
// --------------------
float currentFrame = static_cast<float>(glfwGetTime());
deltaTime = currentFrame - lastFrame;
lastFrame = currentFrame;
// input
// -----
processInput(window);
// move light position over time
lightPos.z = static_cast<float>(sin(glfwGetTime() * 0.5) * 3.0);
// render
// ------
glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// 0. create depth cubemap transformation matrices
// -----------------------------------------------
float near_plane = 1.0f;
float far_plane = 25.0f;
glm::mat4 shadowProj = glm::perspective(glm::radians(90.0f), (float)SHADOW_WIDTH / (float)SHADOW_HEIGHT, near_plane, far_plane);
std::vector<glm::mat4> shadowTransforms;
shadowTransforms.push_back(shadowProj * glm::lookAt(lightPos, lightPos + glm::vec3( 1.0f, 0.0f, 0.0f), glm::vec3(0.0f, -1.0f, 0.0f)));
shadowTransforms.push_back(shadowProj * glm::lookAt(lightPos, lightPos + glm::vec3(-1.0f, 0.0f, 0.0f), glm::vec3(0.0f, -1.0f, 0.0f)));
shadowTransforms.push_back(shadowProj * glm::lookAt(lightPos, lightPos + glm::vec3( 0.0f, 1.0f, 0.0f), glm::vec3(0.0f, 0.0f, 1.0f)));
shadowTransforms.push_back(shadowProj * glm::lookAt(lightPos, lightPos + glm::vec3( 0.0f, -1.0f, 0.0f), glm::vec3(0.0f, 0.0f, -1.0f)));
shadowTransforms.push_back(shadowProj * glm::lookAt(lightPos, lightPos + glm::vec3( 0.0f, 0.0f, 1.0f), glm::vec3(0.0f, -1.0f, 0.0f)));
shadowTransforms.push_back(shadowProj * glm::lookAt(lightPos, lightPos + glm::vec3( 0.0f, 0.0f, -1.0f), glm::vec3(0.0f, -1.0f, 0.0f)));
// 1. render scene to depth cubemap
// --------------------------------
glViewport(0, 0, SHADOW_WIDTH, SHADOW_HEIGHT);
glBindFramebuffer(GL_FRAMEBUFFER, depthMapFBO);
glClear(GL_DEPTH_BUFFER_BIT);
simpleDepthShader.use();
for (unsigned int i = 0; i < 6; ++i)
simpleDepthShader.setMat4("shadowMatrices[" + std::to_string(i) + "]", shadowTransforms[i]);
simpleDepthShader.setFloat("far_plane", far_plane);
simpleDepthShader.setVec3("lightPos", lightPos);
renderScene(simpleDepthShader);
glBindFramebuffer(GL_FRAMEBUFFER, 0);
// 2. render scene as normal
// -------------------------
glViewport(0, 0, SCR_WIDTH, SCR_HEIGHT);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
shader.use();
glm::mat4 projection = glm::perspective(glm::radians(camera.Zoom), (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f);
glm::mat4 view = camera.GetViewMatrix();
shader.setMat4("projection", projection);
shader.setMat4("view", view);
// set lighting uniforms
shader.setVec3("lightPos", lightPos);
shader.setVec3("viewPos", camera.Position);
shader.setInt("shadows", shadows); // enable/disable shadows by pressing 'SPACE'
shader.setFloat("far_plane", far_plane);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, woodTexture);
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_CUBE_MAP, depthCubemap);
renderScene(shader);
// glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.)
// -------------------------------------------------------------------------------
glfwSwapBuffers(window);
glfwPollEvents();
}
glfwTerminate();
return 0;
}
// renders the 3D scene
// --------------------
void renderScene(const Shader &shader)
{
// room cube
glm::mat4 model = glm::mat4(1.0f);
model = glm::scale(model, glm::vec3(5.0f));
shader.setMat4("model", model);
glDisable(GL_CULL_FACE); // note that we disable culling here since we render 'inside' the cube instead of the usual 'outside' which throws off the normal culling methods.
shader.setInt("reverse_normals", 1); // A small little hack to invert normals when drawing cube from the inside so lighting still works.
renderCube();
shader.setInt("reverse_normals", 0); // and of course disable it
glEnable(GL_CULL_FACE);
// cubes
model = glm::mat4(1.0f);
model = glm::translate(model, glm::vec3(4.0f, -3.5f, 0.0));
model = glm::scale(model, glm::vec3(0.5f));
shader.setMat4("model", model);
renderCube();
model = glm::mat4(1.0f);
model = glm::translate(model, glm::vec3(2.0f, 3.0f, 1.0));
model = glm::scale(model, glm::vec3(0.75f));
shader.setMat4("model", model);
renderCube();
model = glm::mat4(1.0f);
model = glm::translate(model, glm::vec3(-3.0f, -1.0f, 0.0));
model = glm::scale(model, glm::vec3(0.5f));
shader.setMat4("model", model);
renderCube();
model = glm::mat4(1.0f);
model = glm::translate(model, glm::vec3(-1.5f, 1.0f, 1.5));
model = glm::scale(model, glm::vec3(0.5f));
shader.setMat4("model", model);
renderCube();
model = glm::mat4(1.0f);
model = glm::translate(model, glm::vec3(-1.5f, 2.0f, -3.0));
model = glm::rotate(model, glm::radians(60.0f), glm::normalize(glm::vec3(1.0, 0.0, 1.0)));
model = glm::scale(model, glm::vec3(0.75f));
shader.setMat4("model", model);
renderCube();
}
// renderCube() renders a 1x1 3D cube in NDC.
// -------------------------------------------------
unsigned int cubeVAO = 0;
unsigned int cubeVBO = 0;
void renderCube()
{
// initialize (if necessary)
if (cubeVAO == 0)
{
float vertices[] = {
// back face
-1.0f, -1.0f, -1.0f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f, // bottom-left
1.0f, 1.0f, -1.0f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f, // top-right
1.0f, -1.0f, -1.0f, 0.0f, 0.0f, -1.0f, 1.0f, 0.0f, // bottom-right
1.0f, 1.0f, -1.0f, 0.0f, 0.0f, -1.0f, 1.0f, 1.0f, // top-right
-1.0f, -1.0f, -1.0f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f, // bottom-left
-1.0f, 1.0f, -1.0f, 0.0f, 0.0f, -1.0f, 0.0f, 1.0f, // top-left
// front face
-1.0f, -1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, // bottom-left
1.0f, -1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f, 0.0f, // bottom-right
1.0f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f, // top-right
1.0f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f, 1.0f, // top-right
-1.0f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, 1.0f, // top-left
-1.0f, -1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, // bottom-left
// left face
-1.0f, 1.0f, 1.0f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-right
-1.0f, 1.0f, -1.0f, -1.0f, 0.0f, 0.0f, 1.0f, 1.0f, // top-left
-1.0f, -1.0f, -1.0f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-left
-1.0f, -1.0f, -1.0f, -1.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-left
-1.0f, -1.0f, 1.0f, -1.0f, 0.0f, 0.0f, 0.0f, 0.0f, // bottom-right
-1.0f, 1.0f, 1.0f, -1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-right
// right face
1.0f, 1.0f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-left
1.0f, -1.0f, -1.0f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-right
1.0f, 1.0f, -1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f, // top-right
1.0f, -1.0f, -1.0f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-right
1.0f, 1.0f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, // top-left
1.0f, -1.0f, 1.0f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, // bottom-left
// bottom face
-1.0f, -1.0f, -1.0f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f, // top-right
1.0f, -1.0f, -1.0f, 0.0f, -1.0f, 0.0f, 1.0f, 1.0f, // top-left
1.0f, -1.0f, 1.0f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f, // bottom-left
1.0f, -1.0f, 1.0f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f, // bottom-left
-1.0f, -1.0f, 1.0f, 0.0f, -1.0f, 0.0f, 0.0f, 0.0f, // bottom-right
-1.0f, -1.0f, -1.0f, 0.0f, -1.0f, 0.0f, 0.0f, 1.0f, // top-right
// top face
-1.0f, 1.0f, -1.0f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f, // top-left
1.0f, 1.0f , 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, // bottom-right
1.0f, 1.0f, -1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f, // top-right
1.0f, 1.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, // bottom-right
-1.0f, 1.0f, -1.0f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f, // top-left
-1.0f, 1.0f, 1.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f // bottom-left
};
glGenVertexArrays(1, &cubeVAO);
glGenBuffers(1, &cubeVBO);
// fill buffer
glBindBuffer(GL_ARRAY_BUFFER, cubeVBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
// link vertex attributes
glBindVertexArray(cubeVAO);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)0);
glEnableVertexAttribArray(1);
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(3 * sizeof(float)));
glEnableVertexAttribArray(2);
glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(6 * sizeof(float)));
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindVertexArray(0);
}
// render Cube
glBindVertexArray(cubeVAO);
glDrawArrays(GL_TRIANGLES, 0, 36);
glBindVertexArray(0);
}
// process all input: query GLFW whether relevant keys are pressed/released this frame and react accordingly
// ---------------------------------------------------------------------------------------------------------
void processInput(GLFWwindow *window)
{
if (glfwGetKey(window, GLFW_KEY_ESCAPE) == GLFW_PRESS)
glfwSetWindowShouldClose(window, true);
if (glfwGetKey(window, GLFW_KEY_W) == GLFW_PRESS)
camera.ProcessKeyboard(FORWARD, deltaTime);
if (glfwGetKey(window, GLFW_KEY_S) == GLFW_PRESS)
camera.ProcessKeyboard(BACKWARD, deltaTime);
if (glfwGetKey(window, GLFW_KEY_A) == GLFW_PRESS)
camera.ProcessKeyboard(LEFT, deltaTime);
if (glfwGetKey(window, GLFW_KEY_D) == GLFW_PRESS)
camera.ProcessKeyboard(RIGHT, deltaTime);
if (glfwGetKey(window, GLFW_KEY_SPACE) == GLFW_PRESS && !shadowsKeyPressed)
{
shadows = !shadows;
shadowsKeyPressed = true;
}
if (glfwGetKey(window, GLFW_KEY_SPACE) == GLFW_RELEASE)
{
shadowsKeyPressed = false;
}
}
// glfw: whenever the window size changed (by OS or user resize) this callback function executes
// ---------------------------------------------------------------------------------------------
void framebuffer_size_callback(GLFWwindow* window, int width, int height)
{
// make sure the viewport matches the new window dimensions; note that width and
// height will be significantly larger than specified on retina displays.
glViewport(0, 0, width, height);
}
// glfw: whenever the mouse moves, this callback is called
// -------------------------------------------------------
void mouse_callback(GLFWwindow* window, double xposIn, double yposIn)
{
float xpos = static_cast<float>(xposIn);
float ypos = static_cast<float>(yposIn);
if (firstMouse)
{
lastX = xpos;
lastY = ypos;
firstMouse = false;
}
float xoffset = xpos - lastX;
float yoffset = lastY - ypos; // reversed since y-coordinates go from bottom to top
lastX = xpos;
lastY = ypos;
camera.ProcessMouseMovement(xoffset, yoffset);
}
// glfw: whenever the mouse scroll wheel scrolls, this callback is called
// ----------------------------------------------------------------------
void scroll_callback(GLFWwindow* window, double xoffset, double yoffset)
{
camera.ProcessMouseScroll(static_cast<float>(yoffset));
}
// utility function for loading a 2D texture from file
// ---------------------------------------------------
unsigned int loadTexture(char const * path)
{
unsigned int textureID;
glGenTextures(1, &textureID);
int width, height, nrComponents;
unsigned char *data = stbi_load(path, &width, &height, &nrComponents, 0);
if (data)
{
GLenum format;
if (nrComponents == 1)
format = GL_RED;
else if (nrComponents == 3)
format = GL_RGB;
else if (nrComponents == 4)
format = GL_RGBA;
glBindTexture(GL_TEXTURE_2D, textureID);
glTexImage2D(GL_TEXTURE_2D, 0, format, width, height, 0, format, GL_UNSIGNED_BYTE, data);
glGenerateMipmap(GL_TEXTURE_2D);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, format == GL_RGBA ? GL_CLAMP_TO_EDGE : GL_REPEAT); // for this tutorial: use GL_CLAMP_TO_EDGE to prevent semi-transparent borders. Due to interpolation it takes texels from next repeat
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, format == GL_RGBA ? GL_CLAMP_TO_EDGE : GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
stbi_image_free(data);
}
else
{
std::cout << "Texture failed to load at path: " << path << std::endl;
stbi_image_free(data);
}
return textureID;
}
HI