正在从learning opengl学习中,再这里作一点简单的记录。
.cpp文件
#include
// GLEW
#define GLEW_STATIC
#include
// GLFW
#include
// Other Libs
#include
#include
#include
#include
// Other includes
#include "Shader.h"
// Function prototypes
void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode);
// Window dimensions
const GLuint WIDTH = 800, HEIGHT = 600;
// Holds uniform value of texture mix
GLfloat mixValue = 0.2f;
// The MAIN function, from here we start the application and run the game loop
int main()
{
// Init GLFW
glfwInit();
// Set all the required options for GLFW
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);
// Create a GLFWwindow object that we can use for GLFW's functions
GLFWwindow* window = glfwCreateWindow(WIDTH, HEIGHT, "LearnOpenGL", nullptr, nullptr);
glfwMakeContextCurrent(window);
// Set the required callback functions
glfwSetKeyCallback(window, key_callback);
// Set this to true so GLEW knows to use a modern approach to retrieving function pointers and extensions
glewExperimental = GL_TRUE;
// Initialize GLEW to setup the OpenGL Function pointers
glewInit();
// Define the viewport dimensions
glViewport(0, 0, WIDTH, HEIGHT);
// Build and compile our shader program
Shader ourShader("path/default.vs", "path/default.frag");
// Set up vertex data (and buffer(s)) and attribute pointers
GLfloat vertices[] = {
-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
};
GLuint indices[] = { // Note that we start from 0!
0, 1, 3, // First Triangle
1, 2, 3 // Second Triangle
};
GLuint VBO, VAO, EBO;
glGenVertexArrays(1, &VAO);
glGenBuffers(1, &VBO);
//glGenBuffers(1, &EBO);
glBindVertexArray(VAO);
glBindBuffer(GL_ARRAY_BUFFER, VBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
//glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO);
//glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices, GL_STATIC_DRAW);
// Position attribute
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)0);
glEnableVertexAttribArray(0);
// Color attribute
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
glEnableVertexAttribArray(1);
// TexCoord attribute
//glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(6 * sizeof(GLfloat)));
//glEnableVertexAttribArray(2);
glBindVertexArray(0); // Unbind VAO
// Load and create a texture
GLuint texture1;
GLuint texture2;
// ====================
// Texture 1
// ====================
glGenTextures(1, &texture1);
glBindTexture(GL_TEXTURE_2D, texture1); // All upcoming GL_TEXTURE_2D operations now have effect on our texture object
// Set our texture parameters
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE); // Set texture wrapping to GL_REPEAT
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
// Set texture filtering
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// Load, create texture and generate mipmaps
int width, height;
unsigned char* image = SOIL_load_image("container.jpg", &width, &height, 0, SOIL_LOAD_RGB);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, image);
glGenerateMipmap(GL_TEXTURE_2D);
SOIL_free_image_data(image);
glBindTexture(GL_TEXTURE_2D, 0); // Unbind texture when done, so we won't accidentily mess up our texture.
// ===================
// Texture 2
// ===================
glGenTextures(1, &texture2);
glBindTexture(GL_TEXTURE_2D, texture2);
// Set our texture parameters
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
// Set texture filtering
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// Load, create texture and generate mipmaps
image = SOIL_load_image("awesomeface.png", &width, &height, 0, SOIL_LOAD_RGB);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, image);
glGenerateMipmap(GL_TEXTURE_2D);
SOIL_free_image_data(image);
glBindTexture(GL_TEXTURE_2D, 0);
// Game loop
while (!glfwWindowShouldClose(window))
{
// Check if any events have been activiated (key pressed, mouse moved etc.) and call corresponding response functions
glfwPollEvents();
// Render
// Clear the colorbuffer
glClearColor(0.2f, 0.3f, 0.3f, 1.0f);
glEnable(GL_DEPTH_TEST);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// Bind Textures using texture units
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, texture1);
glUniform1i(glGetUniformLocation(ourShader.Program, "ourTexture1"), 0);
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, texture2);
glUniform1i(glGetUniformLocation(ourShader.Program, "ourTexture2"), 1);
// Set current value of uniform mix
glUniform1f(glGetUniformLocation(ourShader.Program, "mixValue"), mixValue);
// Activate shader
ourShader.Use();
glm::mat4 model;
model = glm::rotate(model, (GLfloat)glfwGetTime() * 50.0f, glm::vec3(0.5f, 1.0f, 0.0f));
GLint modelLoc = glGetUniformLocation(ourShader.Program, "model");
glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model));
glm::mat4 view;
view = glm::translate(view, glm::vec3(0.0f, 0.0f, -3.0f));
GLint viewLoc = glGetUniformLocation(ourShader.Program, "view");
glUniformMatrix4fv(viewLoc, 1, GL_FALSE, glm::value_ptr(view));
glm::mat4 projection;
projection = glm::perspective(45.0f, (GLfloat)WIDTH / (GLfloat)HEIGHT, 0.1f, 100.0f);
GLint projectionLoc = glGetUniformLocation(ourShader.Program, "projection");
glUniformMatrix4fv(projectionLoc, 1, GL_FALSE, glm::value_ptr(projection));
// Draw container
glBindVertexArray(VAO);
//glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
glDrawArrays(GL_TRIANGLES, 0, 36);
glBindVertexArray(0);
// Swap the screen buffers
glfwSwapBuffers(window);
}
// Properly de-allocate all resources once they've outlived their purpose
glDeleteVertexArrays(1, &VAO);
glDeleteBuffers(1, &VBO);
glDeleteBuffers(1, &EBO);
// Terminate GLFW, clearing any resources allocated by GLFW.
glfwTerminate();
return 0;
}
// Is called whenever a key is pressed/released via GLFW
void key_callback(GLFWwindow* window, int key, int scancode, int action, int mode)
{
cout << key << endl;
if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)
glfwSetWindowShouldClose(window, GL_TRUE);
// Change value of uniform with arrow keys (sets amount of textre mix)
if (key == GLFW_KEY_UP && action == GLFW_PRESS)
{
mixValue += 0.1f;
if (mixValue >= 1.0f)
mixValue = 1.0f;
}
if (key == GLFW_KEY_DOWN && action == GLFW_PRESS)
{
mixValue -= 0.1f;
if (mixValue <= 0.0f)
mixValue = 0.0f;
}
}
Shader.h
#pragma once
#ifndef SHADER_H
#define SHADER_H
#include
#include
#include
#include
#include
#include
using namespace std;
class Shader
{
public:
GLuint Program;
Shader(const GLchar* vertexPath, const GLchar* fragmentPath)
{
string vertexCode, fragmentCode;
ifstream vShaderFile, fShaderFile;
vShaderFile.exceptions(ifstream::badbit);
fShaderFile.exceptions(ifstream::badbit);
try
{
vShaderFile.open(vertexPath);
fShaderFile.open(fragmentPath);
stringstream vShaderStream, fShaderStream;
vShaderStream << vShaderFile.rdbuf();
fShaderStream << fShaderFile.rdbuf();
vShaderFile.close();
fShaderFile.close();
vertexCode = vShaderStream.str();
fragmentCode = fShaderStream.str();
}
catch (std::ifstream::failure e)
{
cout << "ERROR::SHADER::FILE_NOT_SUCCESSFULLY_READ" << endl;
}
const GLchar* vShaderCode = vertexCode.c_str();
const GLchar* fShaderCode = fragmentCode.c_str();
GLint success;
GLchar infoLog[512];
GLuint vertex, fragment;
vertex = glCreateShader(GL_VERTEX_SHADER);
glShaderSource(vertex, 1, &vShaderCode, NULL);
glCompileShader(vertex);
glGetShaderiv(vertex, GL_COMPILE_STATUS, &success);
if (!success)
{
glGetShaderInfoLog(vertex, 512, NULL, infoLog);
cout << "ERROR_CREATE_SHADER\n" << infoLog << endl;
}
fragment = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(fragment, 1, &fShaderCode, NULL);
glCompileShader(fragment);
this->Program = glCreateProgram();
glAttachShader(this->Program, vertex);
glAttachShader(this->Program, fragment);
glLinkProgram(this->Program);
glGetProgramiv(this->Program, GL_LINK_STATUS, &success);
if (!success)
{
glGetProgramInfoLog(this->Program, 512, NULL, infoLog);
cout << "ERROR_CREATE_PROGRAM\n" << infoLog << endl;
}
glDeleteShader(vertex);
glDeleteShader(fragment);
}
void Use()
{
glUseProgram(this->Program);
}
};
#endif
#version 330 core
layout (location = 0) in vec3 position;
layout (location = 2) in vec3 color;
layout (location = 1) in vec2 texCoord;
out vec3 ourColor;
out vec2 TexCoord;
uniform mat4 model;
uniform mat4 view;
uniform mat4 projection;
void main()
{
gl_Position = projection * view * model * vec4(position, 1.0f);
ourColor = color;
TexCoord = vec2(texCoord.x, 1.0 - texCoord.y);
}
fragment Shader
#version 330 core
in vec3 ourColor;
in vec2 TexCoord;
out vec4 color;
uniform sampler2D ourTexture1;
uniform sampler2D ourTexture2;
uniform float mixValue;
void main()
{
color = mix(texture(ourTexture1, TexCoord), texture(ourTexture2, TexCoord), mixValue);
}