1. 材质
cube.vs
#version 330 core
layout (location = 0) in vec3 aPos;
layout (location =0 ) in vec3 aNormal;
out vec3 FragPos;
out vec3 Normal;
uniform mat4 model;
uniform mat4 view;
uniform mat4 projection;
void main()
{
FragPos=vec3(model*vec4(aPos,1.0));
Normal=mat3(transpose(inverse(model)))*aNormal;
gl_Position = projection * view * vec4(FragPos, 1.0);
}cube.fs
#version 330 core
out vec4 FragColor;
in vec3 Normal;
in vec3 FragPos;
struct Material {
vec3 ambient;
vec3 diffuse;
vec3 specular;
float shininess;
};
struct Light {
vec3 position;
vec3 ambient;
vec3 diffuse;
vec3 specular;
};
uniform Material material;
uniform Light light;
uniform vec3 objectColor;
uniform vec3 lightColor;
uniform vec3 lightPos;
uniform vec3 viewPos;
void main()
{
//ambient
vec3 ambient=vec3(0.1)*light.ambient*material.ambient;
//diffuse
vec3 norm=normalize(Normal);
vec3 lightDir=normalize(light.position-FragPos);//光的方向向量是光源位置向量与片段位置向量之间的向量差。
//对norm和lightDir向量进行点乘，计算光源对当前片段实际的漫反射影响
//两个向量之间的角度越大，漫反射分量就会越小，点乘的几何意义也如此
float diff=max(dot(norm,lightDir),0.0);
vec3 diffuse=light.diffuse*(diff*material.diffuse);
//specular
//漫反射是光源指向片段位置。现在这个是摄像机指向片段位置
vec3 viewDir=normalize(viewPos-FragPos);
vec3 reflectDir=reflect(-lightDir,norm);//reflect第一个参数就是要片段指向摄像机位置
float spec=pow(max(dot(viewDir,reflectDir),0.0),material.shininess);
vec3 specular=light.specular*(spec*material.specular);
vec3 result=ambient+diffuse+specular;
FragColor = vec4(result, 1.0);
}main.cpp
#include <glad/glad.h>
#include <GLFW/glfw3.h>
#include <iostream>
#include "stb_image.h"
#include <cmath>
#include "shader.h"
#include "camera.h"
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtc/type_ptr.hpp>
void framebuffer_size_callback(GLFWwindow* window, int width, int height);
void processInput(GLFWwindow* window);
void mouse_callback(GLFWwindow* window, double xpos, double ypos);
void scroll_callback(GLFWwindow* window, double xoffset, double yoffset);
// settings
const unsigned int SCR_WIDTH = 900;
const unsigned int SCR_HEIGHT = 600;
//camera
Camera camera(glm::vec3(0.0f, 0.0f, 3.0f));
float lastX = SCR_WIDTH / 2.0f;
float lastY = SCR_HEIGHT / 2.0f;
bool firstMouse = true;
//timing
float deltaTime = 0.0f;//不同配置绘制速度不同，所以需要这个属性
float lastFrame = 0.0f;
glm::vec3 lightPos(1.2f, 1.0f, 2.0f);
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, "Learn", 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 gloabl opengl state
//=============================
glEnable(GL_DEPTH_TEST);
//build and compile our shader zprogram
//=============================
Shader lightingShader("./cube.vs", "./cube.fs");
Shader lightingCubeShader("./light_cube.vs", "./light_cube.fs");
//set up vertex data
float vertices[] = {
-0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f,
0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f,
0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f,
0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f,
-0.5f, 0.5f, -0.5f, 0.0f, 0.0f, -1.0f,
-0.5f, -0.5f, -0.5f, 0.0f, 0.0f, -1.0f,
-0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f,
0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f,
0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f,
0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f,
-0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f,
-0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f,
-0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f,
-0.5f, 0.5f, -0.5f, -1.0f, 0.0f, 0.0f,
-0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f,
-0.5f, -0.5f, -0.5f, -1.0f, 0.0f, 0.0f,
-0.5f, -0.5f, 0.5f, -1.0f, 0.0f, 0.0f,
-0.5f, 0.5f, 0.5f, -1.0f, 0.0f, 0.0f,
0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f,
0.5f, 0.5f, -0.5f, 1.0f, 0.0f, 0.0f,
0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f,
0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f,
0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 0.0f,
0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f,
-0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f,
0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f,
0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f,
0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f,
-0.5f, -0.5f, 0.5f, 0.0f, -1.0f, 0.0f,
-0.5f, -0.5f, -0.5f, 0.0f, -1.0f, 0.0f,
-0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f,
0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f,
0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f,
0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f,
-0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f,
-0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f
};
//第一个
unsigned int VBO, cubeVAO;
glGenVertexArrays(1, &cubeVAO);
glGenBuffers(1, &VBO);
glBindBuffer(GL_ARRAY_BUFFER, VBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
glBindVertexArray(cubeVAO);
//position attribute
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void*)0);
glEnableVertexAttribArray(0);
//normal attribute
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void*)(3 * sizeof(float)));
glEnableVertexAttribArray(1);
//第二个
unsigned int lightCubeVAO;
glGenVertexArrays(1, &lightCubeVAO);
glBindVertexArray(lightCubeVAO);
glBindBuffer(GL_ARRAY_BUFFER, VBO);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void*)0);
glEnableVertexAttribArray(0);
// render loop
// -----------
while (!glfwWindowShouldClose(window))
{
// per-frame time logic
// --------------------
float currentFrame = static_cast<float>(glfwGetTime());
deltaTime = currentFrame - lastFrame;
lastFrame = currentFrame;
// input
// -----
processInput(window);
// render
// ------
glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// be sure to activate shader when setting uniforms/drawing objects
lightingShader.use();
lightingShader.setVec3("objectColor", 1.0f, 0.5f, 0.31f);
lightingShader.setVec3("viewPos", camera.Position);
//设置光照颜色
glm::vec3 lightColor;
lightColor.x = sin(glfwGetTime() * 2.0f);
lightColor.y = sin(glfwGetTime() * 0.7f);
lightColor.z = sin(glfwGetTime() * 1.3f);
glm::vec3 diffuseColor = lightColor * glm::vec3(0.5f); // 降低影响
glm::vec3 ambientColor = diffuseColor * glm::vec3(0.2f); // 很低的影响
lightingShader.setVec3("light.position", lightPos);
lightingShader.setVec3("light.ambient", ambientColor);
lightingShader.setVec3("light.diffuse", diffuseColor); // 将光照调暗了一些以搭配场景
lightingShader.setVec3("light.specular", 1.0f, 1.0f, 1.0f);
//设置材质颜色
lightingShader.setVec3("material.ambient", 1.0f, 0.5f, 0.31f);
lightingShader.setVec3("material.diffuse", 1.0f, 0.5f, 0.31f);
lightingShader.setVec3("material.specular", 0.5f, 0.5f, 0.5f);
lightingShader.setFloat("material.shininess", 32.0f);
// view/projection transformations
glm::mat4 projection = glm::perspective(glm::radians(camera.Zoom), (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f);
glm::mat4 view = camera.GetViewMatrix();
lightingShader.setMat4("projection", projection);
lightingShader.setMat4("view", view);
// world transformation
glm::mat4 model = glm::mat4(1.0f);
lightingShader.setMat4("model", model);
// render the cube
glBindVertexArray(cubeVAO);
glDrawArrays(GL_TRIANGLES, 0, 36);
// also draw the lamp object
lightingCubeShader.use();
lightingCubeShader.setMat4("projection", projection);
lightingCubeShader.setMat4("view", view);
model = glm::mat4(1.0f);
model = glm::translate(model, lightPos);
model = glm::scale(model, glm::vec3(0.2f)); // a smaller cube
lightingCubeShader.setMat4("model", model);
glBindVertexArray(lightCubeVAO);
glDrawArrays(GL_TRIANGLES, 0, 36);
// glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.)
// -------------------------------------------------------------------------------
glfwSwapBuffers(window);
glfwPollEvents();
}
glDeleteVertexArrays(1, &cubeVAO);
glDeleteVertexArrays(1, &lightCubeVAO);
glDeleteBuffers(1, &VBO);
glfwTerminate();
return 0;
}
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);
}
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));
}
2. 改变光照，同时改变光源颜色
#version 330 core
out vec4 FragColor;
uniform vec4 CubeFragColor;
void main()
{
FragColor = CubeFragColor;
} // also draw the lamp object
lightingCubeShader.use();
lightingCubeShader.setMat4("projection", projection);
lightingCubeShader.setMat4("view", view);
glm::vec4 CubeFragColor = glm::vec4(lightColor, 1.0);
lightingCubeShader.setVec4("CubeFragColor", CubeFragColor);
model = glm::mat4(1.0f);
model = glm::translate(model, lightPos);
model = glm::scale(model, glm::vec3(0.2f)); // a smaller cube
lightingCubeShader.setMat4("model", model);
glBindVertexArray(lightCubeVAO);
glDrawArrays(GL_TRIANGLES, 0, 36); 
