这一节很好理解，不需要多做说明，下面的例子程序的顶点数据和原版例子略有不同，注意法线向量
#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 <shader.h>
#include <camera.h>
#include <model.h>
#include <iostream>
#include <windows.h>
const char *vertexShaderSource = R"1234(#version 330 core
layout (location = 0) in vec3 aPos;
layout (location = 1) in vec3 aNormal;
out vec3 Normal;
out vec3 Position;
uniform mat4 model;
uniform mat4 view;
uniform mat4 projection;
void main()
{
Normal = mat3(transpose(inverse(model))) * aNormal;
Position = vec3(model * vec4(aPos, 1.0));
gl_Position = projection * view * model * vec4(aPos, 1.0);
}
)1234";
const char *fragmentShaderSource = R"1234(#version 330 core
out vec4 FragColor;
in vec3 Normal;
in vec3 Position;
uniform vec3 cameraPos;
uniform samplerCube skybox;
void main()
{
vec3 I = normalize(Position - cameraPos);
vec3 R = reflect(I, normalize(Normal));
FragColor = vec4(texture(skybox, R).rgb, 1.0);
}
)1234";
const char *screenVertexShaderSource = R"1234(#version 330 core
layout (location = 0) in vec2 aPos;
layout (location = 1) in vec2 aTexCoords;
out vec2 TexCoords;
void main()
{
TexCoords = aTexCoords;
gl_Position = vec4(aPos.x, aPos.y, 0.0, 1.0);
}
)1234";
const char *screenFragmentShaderSource = R"1234(#version 330 core
out vec4 FragColor;
in vec2 TexCoords;
uniform sampler2D screenTexture;
void main()
{
vec3 col = texture(screenTexture, TexCoords).rgb;
FragColor = vec4(col, 1.0);
}
)1234";
const char *skyboxVertexShaderSource = R"1234(#version 330 core
layout (location = 0) in vec3 aPos;
out vec3 TexCoords;
uniform mat4 projection;
uniform mat4 view;
void main()
{
TexCoords = aPos;
vec4 pos = projection * view * vec4(aPos, 1.0);
gl_Position = pos.xyww;
}
)1234";
const char *skyboxFragmentShaderSource = R"1234(#version 330 core
out vec4 FragColor;
in vec3 TexCoords;
uniform samplerCube skybox;
void main()
{
FragColor = texture(skybox, TexCoords);
}
)1234";
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);
unsigned int loadCubemap(vector<std::string> faces);
// settings
const unsigned int SCR_WIDTH = 1280;
const unsigned int SCR_HEIGHT = 720;
// 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); // uncomment this statement to fix compilation on OS X
#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);
glDepthFunc(GL_LESS); // always pass the depth test (same effect as glDisable(GL_DEPTH_TEST))
glEnable(GL_CULL_FACE);
glFrontFace(GL_CCW);
// build and compile shaders
// -------------------------
Shader shader(vertexShaderSource, fragmentShaderSource);
Shader screenShader(screenVertexShaderSource, screenFragmentShaderSource);
Shader skyboxShader(skyboxVertexShaderSource, skyboxFragmentShaderSource);
float vertices[] = {
-0.5f, -0.5f, -0.5f,
0.5f, -0.5f, -0.5f,
0.5f, 0.5f, -0.5f,
0.5f, 0.5f, -0.5f,
-0.5f, 0.5f, -0.5f,
-0.5f, -0.5f, -0.5f,
-0.5f, -0.5f, 0.5f,
0.5f, -0.5f, 0.5f,
0.5f, 0.5f, 0.5f,
0.5f, 0.5f, 0.5f,
-0.5f, 0.5f, 0.5f,
-0.5f, -0.5f, 0.5f,
-0.5f, 0.5f, 0.5f,
-0.5f, 0.5f, -0.5f,
-0.5f, -0.5f, -0.5f,
-0.5f, -0.5f, -0.5f,
-0.5f, -0.5f, 0.5f,
-0.5f, 0.5f, 0.5f,
0.5f, 0.5f, 0.5f,
0.5f, 0.5f, -0.5f,
0.5f, -0.5f, -0.5f,
0.5f, -0.5f, -0.5f,
0.5f, -0.5f, 0.5f,
0.5f, 0.5f, 0.5f,
-0.5f, -0.5f, -0.5f,
0.5f, -0.5f, -0.5f,
0.5f, -0.5f, 0.5f,
0.5f, -0.5f, 0.5f,
-0.5f, -0.5f, 0.5f,
-0.5f, -0.5f, -0.5f,
-0.5f, 0.5f, -0.5f,
0.5f, 0.5f, -0.5f,
0.5f, 0.5f, 0.5f,
0.5f, 0.5f, 0.5f,
-0.5f, 0.5f, 0.5f,
-0.5f, 0.5f, -0.5f,
};
// set up vertex data (and buffer(s)) and configure vertex attributes
// ------------------------------------------------------------------
float cubeVertices[] = {
// Back face
-0.5f, -0.5f, -0.5f, 0.0f, 0.0f, 0.0f, 0.0f, -1.0f, // Bottom-left
0.5f, 0.5f, -0.5f, 1.0f, 1.0f, 0.0f, 0.0f, -1.0f, // top-right
0.5f, -0.5f, -0.5f, 1.0f, 0.0f, 0.0f, 0.0f, -1.0f, // bottom-right
0.5f, 0.5f, -0.5f, 1.0f, 1.0f, 0.0f, 0.0f, -1.0f, // top-right
-0.5f, -0.5f, -0.5f, 0.0f, 0.0f, 0.0f, 0.0f, -1.0f, // bottom-left
-0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f, -1.0f, // top-left
// Front face
-0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-left
0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 0.0f, 1.0f,// bottom-right
0.5f, 0.5f, 0.5f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f,// top-right
0.5f, 0.5f, 0.5f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f,// top-right
-0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f, // top-left
-0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, // bottom-left
// Left face
-0.5f, 0.5f, 0.5f, 1.0f, 0.0f, -1.0f, 0.0f, 0.0f, // top-right
-0.5f, 0.5f, -0.5f, 1.0f, 1.0f, -1.0f, 0.0f, 0.0f, // top-left
-0.5f, -0.5f, -0.5f, 0.0f, 1.0f, -1.0f, 0.0f, 0.0f, // bottom-left
-0.5f, -0.5f, -0.5f, 0.0f, 1.0f, -1.0f, 0.0f, 0.0f, // bottom-left
-0.5f, -0.5f, 0.5f, 0.0f, 0.0f, -1.0f, 0.0f, 0.0f, // bottom-right
-0.5f, 0.5f, 0.5f, 1.0f, 0.0f, -1.0f, 0.0f, 0.0f, // top-right
// Right face
0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 1.0f, 0.0f, 0.0f, // top-left
0.5f, -0.5f, -0.5f, 0.0f, 1.0f, 1.0f, 0.0f, 0.0f, // bottom-right
0.5f, 0.5f, -0.5f, 1.0f, 1.0f, 1.0f, 0.0f, 0.0f, // top-right
0.5f, -0.5f, -0.5f, 0.0f, 1.0f, 1.0f, 0.0f, 0.0f, // bottom-right
0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 1.0f, 0.0f, 0.0f, // top-left
0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, // bottom-left
// Bottom face
-0.5f, -0.5f, -0.5f, 0.0f, 1.0f, 0.0f, -1.0f, 0.0f, // top-right
0.5f, -0.5f, -0.5f, 1.0f, 1.0f, 0.0f, -1.0f, 0.0f,// top-left
0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 0.0f, -1.0f, 0.0f,// bottom-left
0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 0.0f, -1.0f, 0.0f,// bottom-left
-0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 0.0f, -1.0f, 0.0f, // bottom-right
-0.5f, -0.5f, -0.5f, 0.0f, 1.0f, 0.0f, -1.0f, 0.0f, // top-right
// Top face
-0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, // top-left
0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f,// bottom-right
0.5f, 0.5f, -0.5f, 1.0f, 1.0f, 0.0f, 1.0f, 0.0f,// top-right
0.5f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f,// bottom-right
-0.5f, 0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, // top-left
-0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f // bottom-left
};
float planeVertices[] = {
// positions // texture Coords (note we set these higher than 1 (together with GL_REPEAT as texture wrapping mode). this will cause the floor texture to repeat)
5.0f, -0.5f, 5.0f, 2.0f, 0.0f, 0.0f, 1.0f, 0.0f,
-5.0f, -0.5f, 5.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f,
-5.0f, -0.5f, -5.0f, 0.0f, 2.0f, 0.0f, 1.0f, 0.0f,
5.0f, -0.5f, 5.0f, 2.0f, 0.0f, 0.0f, 1.0f, 0.0f,
-5.0f, -0.5f, -5.0f, 0.0f, 2.0f, 0.0f, 1.0f, 0.0f,
5.0f, -0.5f, -5.0f, 2.0f, 2.0f, 0.0f, 1.0f, 0.0f,
};
float quadVertices[] = {
// positions // texCoords
-1.0f, 1.0f, 0.0f, 1.0f,
-1.0f, -1.0f, 0.0f, 0.0f,
1.0f, -1.0f, 1.0f, 0.0f,
-1.0f, 1.0f, 0.0f, 1.0f,
1.0f, -1.0f, 1.0f, 0.0f,
1.0f, 1.0f, 1.0f, 1.0f
};
float skyboxVertices[] = {
// positions
-1.0f, 1.0f, -1.0f,
-1.0f, -1.0f, -1.0f,
1.0f, -1.0f, -1.0f,
1.0f, -1.0f, -1.0f,
1.0f, 1.0f, -1.0f,
-1.0f, 1.0f, -1.0f,
-1.0f, -1.0f, 1.0f,
-1.0f, -1.0f, -1.0f,
-1.0f, 1.0f, -1.0f,
-1.0f, 1.0f, -1.0f,
-1.0f, 1.0f, 1.0f,
-1.0f, -1.0f, 1.0f,
1.0f, -1.0f, -1.0f,
1.0f, -1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
1.0f, 1.0f, -1.0f,
1.0f, -1.0f, -1.0f,
-1.0f, -1.0f, 1.0f,
-1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
1.0f, -1.0f, 1.0f,
-1.0f, -1.0f, 1.0f,
-1.0f, 1.0f, -1.0f,
1.0f, 1.0f, -1.0f,
1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
-1.0f, 1.0f, 1.0f,
-1.0f, 1.0f, -1.0f,
-1.0f, -1.0f, -1.0f,
-1.0f, -1.0f, 1.0f,
1.0f, -1.0f, -1.0f,
1.0f, -1.0f, -1.0f,
-1.0f, -1.0f, 1.0f,
1.0f, -1.0f, 1.0f
};
// cube VAO
unsigned int cubeVAO, cubeVBO;
glGenVertexArrays(1, &cubeVAO);
glGenBuffers(1, &cubeVBO);
glBindVertexArray(cubeVAO);
glBindBuffer(GL_ARRAY_BUFFER, cubeVBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(cubeVertices), &cubeVertices, GL_STATIC_DRAW);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)0);
glEnableVertexAttribArray(1);
// 纹理数据，本例不需要纹理，但数据留着不删除，包括纹理坐标也会保留但不用
// glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void*)(3 * sizeof(float)));
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(5 * sizeof(float)));
// plane VAO
unsigned int planeVAO, planeVBO;
glGenVertexArrays(1, &planeVAO);
glGenBuffers(1, &planeVBO);
glBindVertexArray(planeVAO);
glBindBuffer(GL_ARRAY_BUFFER, planeVBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(planeVertices), &planeVertices, GL_STATIC_DRAW);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)0);
glEnableVertexAttribArray(1);
// glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float), (void*)(3 * sizeof(float)));
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float), (void*)(5 * sizeof(float)));
// screen quad VAO
unsigned int quadVAO, quadVBO;
glGenVertexArrays(1, &quadVAO);
glGenBuffers(1, &quadVBO);
glBindVertexArray(quadVAO);
glBindBuffer(GL_ARRAY_BUFFER, quadVBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(quadVertices), &quadVertices, GL_STATIC_DRAW);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 4 * sizeof(float), (void*)0);
glEnableVertexAttribArray(1);
glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 4 * sizeof(float), (void*)(2 * sizeof(float)));
// screen skyboxVertices VAO
unsigned int skyboxVAO, skyboxVBO;
glGenVertexArrays(1, &skyboxVAO);
glGenBuffers(1, &skyboxVBO);
glBindVertexArray(skyboxVAO);
glBindBuffer(GL_ARRAY_BUFFER, skyboxVBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(skyboxVertices), &skyboxVertices, GL_STATIC_DRAW);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void*)0);
// load textures
// -------------
vector<std::string> faces
{
"skybox/right.jpg",
"skybox/left.jpg",
"skybox/top.jpg",
"skybox/bottom.jpg",
"skybox/front.jpg",
"skybox/back.jpg"
};
unsigned int cubeTexture = loadTexture("container.jpg");
unsigned int floorTexture = loadTexture("metal.png");
unsigned int cubemapTexture = loadCubemap(faces);
// shader configuration
// --------------------
shader.use();
shader.setInt("texture1", 0);
screenShader.use();
screenShader.setInt("screenTexture", 0);
skyboxShader.use();
skyboxShader.setInt("skybox", 0);
unsigned int framebuffer;
glGenFramebuffers(1, &framebuffer);
glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
// 生成纹理
unsigned int textureColorbuffer;
glGenTextures(1, &textureColorbuffer);
glBindTexture(GL_TEXTURE_2D, textureColorbuffer);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, 800, 600, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glBindTexture(GL_TEXTURE_2D, 0);
// 将它附加到当前绑定的帧缓冲对象
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, textureColorbuffer, 0);
unsigned int rbo;
glGenRenderbuffers(1, &rbo);
glBindRenderbuffer(GL_RENDERBUFFER, rbo);
glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, 800, 600);
glBindRenderbuffer(GL_RENDERBUFFER, 0);
glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_RENDERBUFFER, rbo);
if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
std::cout << "ERROR::FRAMEBUFFER:: Framebuffer is not complete!" << std::endl;
glBindFramebuffer(GL_FRAMEBUFFER, 0);
// render loop
// -----------
while (!glfwWindowShouldClose(window))
{
// per-frame time logic
// --------------------
float currentFrame = glfwGetTime();
deltaTime = currentFrame - lastFrame;
lastFrame = currentFrame;
// input
// -----
processInput(window);
glm::mat4 model = glm::mat4(1.0f);
glm::mat4 view = camera.GetViewMatrix();
glm::mat4 projection = glm::perspective(glm::radians(camera.Zoom), (float)SCR_WIDTH / (float)SCR_HEIGHT, 0.1f, 100.0f);
// render
// ------
// 第一处理阶段(Pass)
glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // 我们现在不使用模板缓冲
shader.use();
shader.setMat4("view", view);
shader.setMat4("projection", projection);
shader.setVec3("cameraPos", camera.Position);
// floor
glCullFace(GL_FRONT);
glBindVertexArray(planeVAO);
glBindTexture(GL_TEXTURE_2D, floorTexture);
shader.setMat4("model", glm::mat4(1.0f));
glDrawArrays(GL_TRIANGLES, 0, 6);
// cubes
glCullFace(GL_BACK);
glBindVertexArray(cubeVAO);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, cubeTexture);
model = glm::translate(model, glm::vec3(-1.0f, 0.0f, -1.0f));
shader.setMat4("model", model);
glDrawArrays(GL_TRIANGLES, 0, 36);
model = glm::mat4(1.0f);
model = glm::translate(model, glm::vec3(2.0f, 0.0f, 0.0f));
shader.setMat4("model", model);
glDrawArrays(GL_TRIANGLES, 0, 36);
glDepthFunc(GL_LEQUAL);
glm::mat4 skyboxView = glm::mat4(glm::mat3(camera.GetViewMatrix()));
skyboxShader.use();
skyboxShader.setMat4("view", skyboxView);
skyboxShader.setMat4("projection", projection);
glBindVertexArray(skyboxVAO);
glBindTexture(GL_TEXTURE_CUBE_MAP, cubemapTexture);
glDrawArrays(GL_TRIANGLES, 0, 36);
glDepthFunc(GL_LESS);
// 第二处理阶段
glBindFramebuffer(GL_FRAMEBUFFER, 0); // 返回默认
glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT);
screenShader.use();
glBindVertexArray(quadVAO);
glDisable(GL_DEPTH_TEST);
glBindTexture(GL_TEXTURE_2D, textureColorbuffer);
glDrawArrays(GL_TRIANGLES, 0, 6);
glEnable(GL_DEPTH_TEST);
// glfw: swap buffers and poll IO events (keys pressed/released, mouse moved etc.)
// -------------------------------------------------------------------------------
glfwSwapBuffers(window);
glfwPollEvents();
Sleep(100);
}
// optional: de-allocate all resources once they've outlived their purpose:
// ------------------------------------------------------------------------
glDeleteFramebuffers(1, &framebuffer);
glDeleteVertexArrays(1, &cubeVAO);
glDeleteVertexArrays(1, &planeVAO);
glDeleteVertexArrays(1, &quadVAO);
glDeleteBuffers(1, &cubeVBO);
glDeleteBuffers(1, &planeVBO);
glDeleteBuffers(1, &quadVBO);
glfwTerminate();
return 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);
}
// 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 xpos, double ypos)
{
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;
if (glfwGetMouseButton(window, GLFW_MOUSE_BUTTON_RIGHT) == GLFW_PRESS)
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(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);
// 消除小草的边框
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;
}
unsigned int loadCubemap(vector<std::string> faces)
{
unsigned int textureID;
glGenTextures(1, &textureID);
glBindTexture(GL_TEXTURE_CUBE_MAP, textureID);
int width, height, nrChannels;
for (unsigned int i = 0; i < faces.size(); i++)
{
unsigned char *data = stbi_load(faces[i].c_str(), &width, &height, &nrChannels, 0);
if (data)
{
glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i,
0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, data
);
stbi_image_free(data);
}
else
{
std::cout << "Cubemap texture failed to load at path: " << faces[i] << std::endl;
stbi_image_free(data);
}
}
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
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);
return textureID;
}
