OpenGL 深度测试1

main.cpp

#include <string>#define GLEW_STATIC#include <GL/glew.h>#include <GLFW/glfw3.h>#include "Shader.h"#include "Camera.h"#include <glm/glm.hpp>#include <glm/gtc/matrix_transform.hpp>#include <glm/gtc/type_ptr.hpp>#include <SOIL/SOIL.h>#pragma comment(lib, "./SOIL.lib")#pragma comment (lib, "opengl32.lib")#pragma comment (lib, "glew32s.lib")#pragma comment (lib, "glfw3.lib") #pragma comment (lib, "glfw3dll.lib") #pragma comment (lib, "glew32mxs.lib")#pragma comment (lib, "assimp.lib")// -*********************************************************-GLuint screenWidth = 800, screenHeight = 600;void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode);void scroll_callback(GLFWwindow* window, double xoffset, double yoffset);void mouse_callback(GLFWwindow* window, double xpos, double ypos);void Do_Movement();GLuint loadTexture(GLchar* path);Camera camera(glm::vec3(0.0f, 0.0f, 3.0f));bool keys[1024];GLfloat lastX = 400, lastY = 300;bool firstMouse = true;GLfloat deltaTime = 0.0f;GLfloat lastFrame = 0.0f;// -*********************************************************-int main(){// Init GLFWglfwInit();glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);glfwWindowHint(GLFW_RESIZABLE, GL_FALSE);GLFWwindow* window = glfwCreateWindow(screenWidth, screenHeight, "LearnOpenGL", nullptr, nullptr);glfwMakeContextCurrent(window);glfwSetKeyCallback(window, key_callback);glfwSetCursorPosCallback(window, mouse_callback);glfwSetScrollCallback(window, scroll_callback);glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);glewExperimental = GL_TRUE;glewInit();glViewport(0, 0, screenWidth, screenHeight);// 启用深度测试glEnable(GL_DEPTH_TEST);glDepthFunc(GL_ALWAYS); // 指定深度缓冲比较函数, 输入的深度值和参考值不论大小, 总是通过// Setup and compile our shadersShader shader("./vertex", "./fragement");GLfloat cubeVertices[] = {// 立方体位置 // 纹理-0.5f, -0.5f, -0.5f,  0.0f, 0.0f,0.5f, -0.5f, -0.5f,  1.0f, 0.0f,0.5f,  0.5f, -0.5f,  1.0f, 1.0f,0.5f,  0.5f, -0.5f,  1.0f, 1.0f,-0.5f,  0.5f, -0.5f,  0.0f, 1.0f,-0.5f, -0.5f, -0.5f,  0.0f, 0.0f,-0.5f, -0.5f,  0.5f,  0.0f, 0.0f,0.5f, -0.5f,  0.5f,  1.0f, 0.0f,0.5f,  0.5f,  0.5f,  1.0f, 1.0f,0.5f,  0.5f,  0.5f,  1.0f, 1.0f,-0.5f,  0.5f,  0.5f,  0.0f, 1.0f,-0.5f, -0.5f,  0.5f,  0.0f, 0.0f,-0.5f,  0.5f,  0.5f,  1.0f, 0.0f,-0.5f,  0.5f, -0.5f,  1.0f, 1.0f,-0.5f, -0.5f, -0.5f,  0.0f, 1.0f,-0.5f, -0.5f, -0.5f,  0.0f, 1.0f,-0.5f, -0.5f,  0.5f,  0.0f, 0.0f,-0.5f,  0.5f,  0.5f,  1.0f, 0.0f,0.5f,  0.5f,  0.5f,  1.0f, 0.0f,0.5f,  0.5f, -0.5f,  1.0f, 1.0f,0.5f, -0.5f, -0.5f,  0.0f, 1.0f,0.5f, -0.5f, -0.5f,  0.0f, 1.0f,0.5f, -0.5f,  0.5f,  0.0f, 0.0f,0.5f,  0.5f,  0.5f,  1.0f, 0.0f,-0.5f, -0.5f, -0.5f,  0.0f, 1.0f,0.5f, -0.5f, -0.5f,  1.0f, 1.0f,0.5f, -0.5f,  0.5f,  1.0f, 0.0f,0.5f, -0.5f,  0.5f,  1.0f, 0.0f,-0.5f, -0.5f,  0.5f,  0.0f, 0.0f,-0.5f, -0.5f, -0.5f,  0.0f, 1.0f,-0.5f,  0.5f, -0.5f,  0.0f, 1.0f,0.5f,  0.5f, -0.5f,  1.0f, 1.0f,0.5f,  0.5f,  0.5f,  1.0f, 0.0f,0.5f,  0.5f,  0.5f,  1.0f, 0.0f,-0.5f,  0.5f,  0.5f,  0.0f, 0.0f,-0.5f,  0.5f, -0.5f,  0.0f, 1.0f};// 草地GLfloat planeVertices[] = {// 位置            // 纹理 大于1,使得可以重复5.0f,  -0.5f,  5.0f,  2.0f, 0.0f,-5.0f, -0.5f,  5.0f,  0.0f, 0.0f,-5.0f, -0.5f, -5.0f,  0.0f, 2.0f,5.0f,  -0.5f,  5.0f,  2.0f, 0.0f,-5.0f, -0.5f, -5.0f,  0.0f, 2.0f,5.0f,  -0.5f, -5.0f,  2.0f, 2.0f};// 立方体数据设置GLuint cubeVAO, cubeVBO;glGenVertexArrays(1, &cubeVAO);glBindVertexArray(cubeVAO);glGenBuffers(1, &cubeVBO);glBindBuffer(GL_ARRAY_BUFFER, cubeVBO);glBufferData(GL_ARRAY_BUFFER, sizeof(cubeVertices), &cubeVertices, GL_STATIC_DRAW);glEnableVertexAttribArray(0);glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)0);glEnableVertexAttribArray(1);glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));glBindVertexArray(0);// 草地数据设置GLuint planeVAO, planeVBO;glGenVertexArrays(1, &planeVAO);glBindVertexArray(planeVAO);glGenBuffers(1, &planeVBO);glBindBuffer(GL_ARRAY_BUFFER, planeVBO);glBufferData(GL_ARRAY_BUFFER, sizeof(planeVertices), &planeVertices, GL_STATIC_DRAW);glEnableVertexAttribArray(0);glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)0);glEnableVertexAttribArray(1);glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));glBindVertexArray(0);// 加载纹理GLuint cubeTexture = loadTexture("./a.jpg");GLuint floorTexture = loadTexture("./b.jpg");while (!glfwWindowShouldClose(window)){GLfloat currentFrame = glfwGetTime();deltaTime = currentFrame - lastFrame;lastFrame = currentFrame;glfwPollEvents();Do_Movement();glClearColor(0.1f, 0.15f, 0.25f, 1.0f);glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);shader.useShaderPrograme();// 视图设置glm::mat4 model;glm::mat4 view = camera.GetViewMatrix();glm::mat4 projection = glm::perspective(camera.Zoom, (float)screenWidth / (float)screenHeight, 0.1f, 100.0f);glUniformMatrix4fv(glGetUniformLocation(shader.getPrograme(), "view"), 1, GL_FALSE, glm::value_ptr(view));glUniformMatrix4fv(glGetUniformLocation(shader.getPrograme(), "projection"), 1, GL_FALSE, glm::value_ptr(projection));// 立方体绘制glBindVertexArray(cubeVAO);glBindTexture(GL_TEXTURE_2D, cubeTexture);model = glm::translate(model, glm::vec3(-1.0f, 0.0f, -1.0f));glUniformMatrix4fv(glGetUniformLocation(shader.getPrograme(), "model"), 1, GL_FALSE, glm::value_ptr(model));glDrawArrays(GL_TRIANGLES, 0, 36);model = glm::mat4();model = glm::translate(model, glm::vec3(2.0f, 0.0f, 0.0f));glUniformMatrix4fv(glGetUniformLocation(shader.getPrograme(), "model"), 1, GL_FALSE, glm::value_ptr(model));glDrawArrays(GL_TRIANGLES, 0, 36);// 草地绘制glBindVertexArray(planeVAO);glBindTexture(GL_TEXTURE_2D, floorTexture);model = glm::mat4();glUniformMatrix4fv(glGetUniformLocation(shader.getPrograme(), "model"), 1, GL_FALSE, glm::value_ptr(model));glDrawArrays(GL_TRIANGLES, 0, 6);glBindVertexArray(0);glfwSwapBuffers(window);}glfwTerminate();return 0;}// -*********************************************************-// 加载纹理GLuint loadTexture(GLchar* path){GLuint textureID;glGenTextures(1, &textureID);int width, height;unsigned char* image = SOIL_load_image(path, &width, &height, 0, SOIL_LOAD_RGB);glBindTexture(GL_TEXTURE_2D, textureID);glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, image);glGenerateMipmap(GL_TEXTURE_2D);glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);glBindTexture(GL_TEXTURE_2D, 0);SOIL_free_image_data(image);return textureID;}// -*********************************************************-// 键盘 WSADvoid Do_Movement(){// Camera controlsif (keys[GLFW_KEY_W])camera.ProcessKeyboard(FORWARD, deltaTime);if (keys[GLFW_KEY_S])camera.ProcessKeyboard(BACKWARD, deltaTime);if (keys[GLFW_KEY_A])camera.ProcessKeyboard(LEFT, deltaTime);if (keys[GLFW_KEY_D])camera.ProcessKeyboard(RIGHT, deltaTime);}void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode){if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)glfwSetWindowShouldClose(window, GL_TRUE);if (action == GLFW_PRESS)keys[key] = true;else if (action == GLFW_RELEASE)keys[key] = false;}// -*********************************************************-// 鼠标void mouse_callback(GLFWwindow* window, double xpos, double ypos){if (firstMouse){lastX = xpos;lastY = ypos;firstMouse = false;}GLfloat xoffset = xpos - lastX;GLfloat yoffset = lastY - ypos;lastX = xpos;lastY = ypos;camera.ProcessMouseMovement(xoffset, yoffset);}void scroll_callback(GLFWwindow* window, double xoffset, double yoffset){camera.ProcessMouseScroll(yoffset);}

Camera.h

//Camera.h #pragma once// Std. Includes#include <vector>// GL Includes#include <GL/glew.h>#include <glm/glm.hpp>#include <glm/gtc/matrix_transform.hpp>// 摄像机移动方向  程序中用WSAD控制enum Camera_Movement {FORWARD,BACKWARD,LEFT,RIGHT};// Default camera valuesconst GLfloat YAW = -90.0f;const GLfloat PITCH = 0.0f;const GLfloat SPEED = 3.0f;const GLfloat SENSITIVTY = 0.25f;const GLfloat ZOOM = 45.0f;class Camera{public:// Camera Attributesglm::vec3 Position;glm::vec3 Front;glm::vec3 Up;glm::vec3 Right;glm::vec3 WorldUp;// Eular AnglesGLfloat Yaw;GLfloat Pitch;// Camera optionsGLfloat MovementSpeed;GLfloat MouseSensitivity;GLfloat Zoom;// Constructor with vectorsCamera(glm::vec3 position = glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3 up = glm::vec3(0.0f, 1.0f, 0.0f), GLfloat yaw = YAW, GLfloat pitch = PITCH) : Front(glm::vec3(0.0f, 0.0f, -1.0f)), MovementSpeed(SPEED), MouseSensitivity(SENSITIVTY), Zoom(ZOOM){this->Position = position;this->WorldUp = up;this->Yaw = yaw;this->Pitch = pitch;this->updateCameraVectors();}// Constructor with scalar valuesCamera(GLfloat posX, GLfloat posY, GLfloat posZ, GLfloat upX, GLfloat upY, GLfloat upZ, GLfloat yaw, GLfloat pitch) : Front(glm::vec3(0.0f, 0.0f, -1.0f)), MovementSpeed(SPEED), MouseSensitivity(SENSITIVTY), Zoom(ZOOM){this->Position = glm::vec3(posX, posY, posZ);this->WorldUp = glm::vec3(upX, upY, upZ);this->Yaw = yaw;this->Pitch = pitch;this->updateCameraVectors();}// Returns the view matrix calculated using Eular Angles and the LookAt Matrixglm::mat4 GetViewMatrix(){return glm::lookAt(this->Position, this->Position + this->Front, this->Up);}// 按键处理void ProcessKeyboard(Camera_Movement direction, GLfloat deltaTime){GLfloat velocity = this->MovementSpeed * deltaTime;if (direction == FORWARD)this->Position += this->Front * velocity;if (direction == BACKWARD)this->Position -= this->Front * velocity;if (direction == LEFT)this->Position -= this->Right * velocity;if (direction == RIGHT)this->Position += this->Right * velocity;}// 鼠标移动处理void ProcessMouseMovement(GLfloat xoffset, GLfloat yoffset, GLboolean constrainPitch = true){xoffset *= this->MouseSensitivity;yoffset *= this->MouseSensitivity;this->Yaw += xoffset;this->Pitch += yoffset;// Make sure that when pitch is out of bounds, screen doesn't get flippedif (constrainPitch){if (this->Pitch > 89.0f)this->Pitch = 89.0f;if (this->Pitch < -89.0f)this->Pitch = -89.0f;}// Update Front, Right and Up Vectors using the updated Eular anglesthis->updateCameraVectors();}// Processes input received from a mouse scroll-wheel event. //Only requires input on the vertical wheel-axisvoid ProcessMouseScroll(GLfloat yoffset){if (this->Zoom >= 1.0f && this->Zoom <= 45.0f)this->Zoom -= yoffset;if (this->Zoom <= 1.0f)this->Zoom = 1.0f;if (this->Zoom >= 45.0f)this->Zoom = 45.0f;}private:// Calculates the front vector from the Camera's (updated) Eular Anglesvoid updateCameraVectors(){// Calculate the new Front vectorglm::vec3 front;front.x = cos(glm::radians(this->Yaw)) * cos(glm::radians(this->Pitch));front.y = sin(glm::radians(this->Pitch));front.z = sin(glm::radians(this->Yaw)) * cos(glm::radians(this->Pitch));this->Front = glm::normalize(front);// Also re-calculate the Right and Up vector// Normalize the vectors, because their length gets closer to 0 the more //you look up or down which results in slower movement.this->Right = glm::normalize(glm::cross(this->Front, this->WorldUp));  this->Up = glm::normalize(glm::cross(this->Right, this->Front));}};

Shader.h

//Shader.h #pragma once#ifndef TEXTURE_SHADER_H_#define TEXTURE_SHADER_H_#include <string>#include <fstream>#include <sstream>#include <iostream>#include <gl/glew.h>#include <string>#include <fstream>#include <sstream>#include <iostream>#include <GL/glew.h>class Shader{public:Shader(const GLchar* vertexPath, const GLchar* fragmentPath);~Shader();public:void useShaderPrograme();GLuint getPrograme() {return this->m_nProgram;}private:GLuint  m_nProgram;};Shader::Shader(const GLchar* vertexPath, const GLchar* fragmentPath){std::string vertexCode;std::string fragmentCode;std::ifstream vertexShaderF;std::ifstream fragementShaderF;vertexShaderF.exceptions(std::ifstream::badbit);fragementShaderF.exceptions(std::ifstream::badbit);try{vertexShaderF.open(vertexPath);// 打开文件fragementShaderF.open(fragmentPath);std::stringstream vertexShaderStream, fragementShaderStream;vertexShaderStream << vertexShaderF.rdbuf();// 读取文件至stringstream中fragementShaderStream << fragementShaderF.rdbuf();vertexShaderF.close();fragementShaderF.close();vertexCode = vertexShaderStream.str();// 转换成string类型fragmentCode = fragementShaderStream.str();}catch (std::ifstream::failure e){std::cout << "ERROR::SHADER::FILE_NOT_SUCCESSFULLY_READ:" << std::endl;}const GLchar* pVertexCode = vertexCode.c_str();// string 转 char*const GLchar* pFragementCode = fragmentCode.c_str();GLuint nVertexShader, nFragementShader;GLint nRes = 0;GLchar chLogInfo[512] = { '\0' };// 创建顶点着色器nVertexShader = glCreateShader(GL_VERTEX_SHADER);// 将顶点着色程序的源代码字符数组绑定到顶点着色器对象glShaderSource(nVertexShader, 1, &pVertexCode, nullptr);glCompileShader(nVertexShader); // compile shader 编译着色器// 获取编译结果glGetShaderiv(nVertexShader, GL_COMPILE_STATUS, &nRes);if (!nRes){glGetShaderInfoLog(nVertexShader, 512, nullptr, chLogInfo);std::cout << "ERROR::SHADEF::VERTEX::COMPILATION_FAILED:" << chLogInfo << std::endl;}// 创建片断着色器nFragementShader = glCreateShader(GL_FRAGMENT_SHADER);// 将片段着色程序的源代码字符数组绑定到片段着色器对象glShaderSource(nFragementShader, 1, &pFragementCode, nullptr);glCompileShader(nFragementShader);glGetShaderiv(nFragementShader, GL_COMPILE_STATUS, &nRes);if (!nRes){glGetShaderInfoLog(nFragementShader, 512, nullptr, chLogInfo);std::cout << "ERROR::SHADEF::FRAGEMENT::COMPILATION_FAILED:" << chLogInfo << std::endl;}this->m_nProgram = glCreateProgram();// 创建GLSL程序glAttachShader(this->m_nProgram, nVertexShader);// 绑定shader到programglAttachShader(this->m_nProgram, nFragementShader);// glLinkProgram操作产生最后的可执行程序，它包含最后可以在硬件上执行的硬件指令glLinkProgram(this->m_nProgram);// 链接glGetProgramiv(this->m_nProgram, GL_LINK_STATUS, &nRes);if (!nRes){glGetProgramInfoLog(this->m_nProgram, 512, nullptr, chLogInfo);std::cout << "ERROR::SHADEF::FRAGEMENT::LINK_FAILED:" << chLogInfo << std::endl;}glDeleteShader(nVertexShader);glDeleteShader(nFragementShader);}Shader::~Shader(){}#include <glm/glm.hpp>#include <glm/gtc/matrix_transform.hpp>#include <glm/gtc/type_ptr.hpp>void Shader::useShaderPrograme(){glUseProgram(this->m_nProgram);// 使用porgram}#endif

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Shader 源码部分

vertex

// Vertex shader:// ================#version 330 corelayout (location = 0) in vec3 position;layout (location = 1) in vec2 texCoords;out vec2 TexCoords;uniform mat4 model;uniform mat4 view;uniform mat4 projection;void main(){    gl_Position = projection * view * model * vec4(position, 1.0f);    TexCoords = texCoords;}

fragement

// Fragment shader:// ================#version 330 corein vec2 TexCoords;out vec4 color;uniform sampler2D texture1;void main(){                 color = texture(texture1, TexCoords);}

来源:

http://learnopengl-cn.readthedocs.io/zh/latest/04%20Advanced%20OpenGL/01%20Depth%20testing/

源码:

http://download.csdn.net/detail/yulinxx/9716607