OpenGL-- Shader 颜色 光照
参考:
http://learnopengl-cn.readthedocs.io/zh/latest/02%20Lighting/02%20Basic%20Lighting/
1. 主程序
#include
#define GLEW_STATIC
#include
#include
#include "Shader.h"
#include "Camera.h"
#include
#include
#include
#include
#include
#define GLEW_STATIC
#include
#include
#include
#include
#include
#include "TextureShader.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")
void key_callback(GLFWwindow* pWnd, int key, int scancode, int action, int mode);
void mouse_callback(GLFWwindow* pWnd, double xpos, double ypos);
void scroll_callback(GLFWwindow* pWnd, double xoffset, double yoffset);
void do_movement();
const GLuint WIDTH = 800, HEIGHT = 600;
Camera camera(glm::vec3(0.0f, 0.0f, 3.0f));
GLfloat lastX = WIDTH / 2.0;
GLfloat lastY = HEIGHT / 2.0;
bool keys[1024];
glm::vec3 lightPos(1.2f, 1.0f, 2.0f);
GLfloat deltaTime = 0.0f;
GLfloat lastFrame = 0.0f;
/////////////////////////////////////////////////////////////////////////
int main()
{
glfwInit();
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* pWnd = glfwCreateWindow(WIDTH, HEIGHT, "LearnOpenGL", nullptr, nullptr);
glfwMakeContextCurrent(pWnd);
glfwSetKeyCallback(pWnd, key_callback);
glfwSetCursorPosCallback(pWnd, mouse_callback);
glfwSetScrollCallback(pWnd, scroll_callback);
// 鼠标隐藏
//glfwSetInputMode(pWnd, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
glewExperimental = GL_TRUE;
glewInit();
glViewport(0, 0, WIDTH, HEIGHT);
glEnable(GL_DEPTH_TEST);
Shader lightingObjShader("./obj_vertex", "./obj_fragement");
Shader lampShader("./lamp_vertex", "./lamp_fragement");
GLfloat vertices[] = { // 顶点 向量
- 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
};
glm::vec3 objPos[] = {
glm::vec3(-3.0f, -1.0f, -5.0f), glm::vec3(2.0f, 5.0f, -1.0f),
glm::vec3(-1.5f, -2.2f, -2.5f), glm::vec3(0.0f, -2.0f, -5.3f),
glm::vec3(2.4f, -0.4f, -3.5f), glm::vec3(-1.7f, 0.0f, -7.5f),
glm::vec3(1.3f, -2.0f, -2.5f), glm::vec3(1.5f, 2.0f, -2.5f),
glm::vec3(1.5f, 0.2f, -1.5f), glm::vec3(-1.3f, 1.0f, -1.5f) };
GLuint VBO, objVAO;
glGenVertexArrays(1, &objVAO);
glGenBuffers(1, &VBO);
glBindBuffer(GL_ARRAY_BUFFER, VBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW); // 顶点复至GPU中
// 光照物体
glBindVertexArray(objVAO); // --- Begin
// 位置索引
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(GLfloat), (GLvoid*)0);
glEnableVertexAttribArray(0);
// 向量索引
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
glEnableVertexAttribArray(1);
glBindVertexArray(0); // --- End
// 灯泡 (只需要用到一部分坐标点数据,用于绘制一个立方体即可)
GLuint lampVAO;
glGenVertexArrays(1, &lampVAO);
glBindVertexArray(lampVAO);
glBindBuffer(GL_ARRAY_BUFFER, VBO);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(GLfloat), (GLvoid*)0);
glEnableVertexAttribArray(0);
glBindVertexArray(0);
GLuint nCurrentTime = glfwGetTime();
GLuint nLastTime = glfwGetTime();
GLuint nFPS = 0;
while (!glfwWindowShouldClose(pWnd))
{
GLfloat currentFrame = glfwGetTime();
deltaTime = currentFrame - lastFrame;
lastFrame = currentFrame;
glfwPollEvents();
do_movement();
glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// 视图设置
glm::mat4 view;
view = camera.GetViewMatrix();
glm::mat4 projection = glm::perspective(camera.Zoom, (GLfloat)WIDTH / (GLfloat)HEIGHT, 0.1f, 100.0f);
// -----------------------------------------------
// 绘制光照物体
lightingObjShader.useShaderPrograme();
GLint objectColorLoc = glGetUniformLocation(lightingObjShader.getPrograme(), "objectColor");
GLint lightColorLoc = glGetUniformLocation(lightingObjShader.getPrograme(), "lightColor");
GLint lightPosLoc = glGetUniformLocation(lightingObjShader.getPrograme(), "lightPos");
GLint viewPosLoc = glGetUniformLocation(lightingObjShader.getPrograme(), "viewPos");
glUniform3f(objectColorLoc, 1.0f, 0.5f, 0.31f); // 物体颜色
glUniform3f(lightColorLoc, 1.0f, 1.0f, 1.0f); // 光照颜色
glUniform3f(lightPosLoc, lightPos.x, lightPos.y, lightPos.z); // 灯光位置
glUniform3f(viewPosLoc, camera.Position.x, camera.Position.y, camera.Position.z); // 观察点位置
GLint modelLoc = glGetUniformLocation(lightingObjShader.getPrograme(), "model");
GLint viewLoc = glGetUniformLocation(lightingObjShader.getPrograme(), "view");
GLint projLoc = glGetUniformLocation(lightingObjShader.getPrograme(), "projection");
// Pass the matrices to the shader
glUniformMatrix4fv(viewLoc, 1, GL_FALSE, glm::value_ptr(view));
glUniformMatrix4fv(projLoc, 1, GL_FALSE, glm::value_ptr(projection));
glm::mat4 model = glm::mat4();
glBindVertexArray(objVAO); // --- Begin
for (GLuint i = 0; i < 10; i++)
{
model = glm::mat4();
model = glm::translate(model, objPos[i]);
GLfloat angle = glfwGetTime();
model = glm::rotate(model, angle, glm::vec3(1.0f, 0.3f, 0.5f));
glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model));
glDrawArrays(GL_TRIANGLES, 0, 36);
}
glBindVertexArray(0); // --- End
// -----------------------------------------------
// -----------------------------------------------
// 绘制灯泡
lampShader.useShaderPrograme();
modelLoc = glGetUniformLocation(lampShader.getPrograme(), "model");
viewLoc = glGetUniformLocation(lampShader.getPrograme(), "view");
projLoc = glGetUniformLocation(lampShader.getPrograme(), "projection");
glUniformMatrix4fv(viewLoc, 1, GL_FALSE, glm::value_ptr(view));
glUniformMatrix4fv(projLoc, 1, GL_FALSE, glm::value_ptr(projection));
model = glm::mat4();
model = glm::translate(model, lightPos);
model = glm::scale(model, glm::vec3(0.2f)); // Make it a smaller cube
glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model));
glBindVertexArray(lampVAO); // --- Begin
glDrawArrays(GL_TRIANGLES, 0, 36);
glBindVertexArray(0); // --- End
// -----------------------------------------------
// Swap the screen buffers
glfwSwapBuffers(pWnd);
nLastTime = glfwGetTime();
nFPS++;
if (nLastTime - nCurrentTime > 1)
{
std::cout << "当前帧率:" << nFPS << std::endl;
nFPS = 0;
nCurrentTime = nLastTime;
}
}
// 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* pWnd, int key, int scancode, int action, int mode)
{
if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)
glfwSetWindowShouldClose(pWnd, GL_TRUE);
if (key >= 0 && key < 1024)
{
if (action == GLFW_PRESS)
keys[key] = true;
else if (action == GLFW_RELEASE)
keys[key] = false;
}
}
void do_movement()
{
// Camera controls
if (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);
}
bool firstMouse = true;
void mouse_callback(GLFWwindow* pWnd, double xpos, double ypos)
{
if (firstMouse)
{
lastX = xpos;
lastY = ypos;
firstMouse = false;
}
GLfloat xoffset = xpos - lastX;
GLfloat yoffset = lastY - ypos; // Reversed since y-coordinates go from bottom to left
lastX = xpos;
lastY = ypos;
//camera.ProcessMouseMovement(xoffset, yoffset);
}
void scroll_callback(GLFWwindow* pWnd, double xoffset, double yoffset)
{
camera.ProcessMouseScroll(yoffset);
} 2. Shader设置
#pragma once
#ifndef TEXTURE_SHADER_H_
#define TEXTURE_SHADER_H_
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
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program
glAttachShader(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
#include
#include
void Shader::useShaderPrograme()
{
glUseProgram(this->m_nProgram); // 使用porgram
}
#endif
3.Camera.h
#pragma once
// Std. Includes
#include
// GL Includes
#include
#include
#include
// Defines several possible options for camera movement. Used as abstraction to stay away from pWnd-system specific input methods
enum Camera_Movement {
FORWARD,
BACKWARD,
LEFT,
RIGHT
};
// Default camera values
const GLfloat YAW = -90.0f;
const GLfloat PITCH = 0.0f;
const GLfloat SPEED = 3.0f;
const GLfloat SENSITIVTY = 0.25f;
const GLfloat ZOOM = 45.0f;
// An abstract camera class that processes input and calculates the corresponding Eular Angles, Vectors and Matrices for use in OpenGL
class Camera
{
public:
// Camera Attributes
glm::vec3 Position;
glm::vec3 Front;
glm::vec3 Up;
glm::vec3 Right;
glm::vec3 WorldUp;
// Eular Angles
GLfloat Yaw;
GLfloat Pitch;
// Camera options
GLfloat MovementSpeed;
GLfloat MouseSensitivity;
GLfloat Zoom;
// Constructor with vectors
Camera(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 values
Camera(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 Matrix
glm::mat4 GetViewMatrix()
{
return glm::lookAt(this->Position, this->Position + this->Front, this->Up);
}
// Processes input received from any keyboard-like input system. Accepts input parameter in the form of camera defined ENUM (to abstract it from windowing systems)
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;
}
// Processes input received from a mouse input system. Expects the offset value in both the x and y direction.
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 flipped
if (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 angles
this->updateCameraVectors();
}
// Processes input received from a mouse scroll-wheel event. Only requires input on the vertical wheel-axis
void 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 Angles
void updateCameraVectors()
{
// Calculate the new Front vector
glm::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
this->Right = glm::normalize(glm::cross(this->Front, this->WorldUp)); // Normalize the vectors, because their length gets closer to 0 the more you look up or down which results in slower movement.
this->Up = glm::normalize(glm::cross(this->Right, this->Front));
}
}; 4.灯泡顶点着色器 lamp_vertex
#version 330 core
layout (location = 0) in vec3 position;
uniform mat4 model;
uniform mat4 view;
uniform mat4 projection;
void main()
{
gl_Position = projection * view * model * vec4(position, 1.0f);
}5.灯泡片断着色器lamp_fragement
#version 330 core
out vec4 color;
in vec3 Normal;
void main()
{
color = vec4(1.0f); // 灯泡为白色
}6.物体顶点着色器 obj_vertex
#version 330 core
// 位置顶点 及 位置顶点的向量
layout (location = 0) in vec3 position;
layout (location = 1) in vec3 normal;
uniform mat4 model;
uniform mat4 view;
uniform mat4 projection;
out vec3 FragPos;
out vec3 Normal;
void main()
{
gl_Position = projection * view * model * vec4(position, 1.0f);
FragPos = vec3(model * vec4(position, 1.0f));
Normal = normal;
}7.物体片断着色器 obj_fragement
#version 330 core
in vec3 FragPos;
in vec3 Normal;
out vec4 color;
uniform vec3 lightPos;
uniform vec3 objectColor;
uniform vec3 lightColor;
void main()
{
// Ambient 环境光强度为灯光的0.1
float ambientStrength = 0.1f;
vec3 ambient = ambientStrength * lightColor;
// Diffuse 漫反射强度
// 为光线到物体的向量 与 物体表面向量 的点乘
vec3 norm = normalize(Normal);
vec3 lightDir = normalize(lightPos - FragPos);
float diff = max(dot(norm, lightDir), 0.0);
vec3 diffuse = diff * lightColor;
// 最终光线为 (环境光强 + 漫反射光强) 与物体颜色的乘积
vec3 result = (ambient + diffuse) * objectColor;
color = vec4(result, 1.0f);
}
