void FrameBufferObject::setSize(unsigned int width, unsigned height)
{
if (initialized)
{
this->width = width;
this->height = height;
if(enableDepth)
initDepthBuffer();
if(enableColor)
initColorBuffer();
}
}
void FrameBufferObject::init(unsigned int width, unsigned height)
{
if (!initialized)
{
this->width = width;
this->height = height;
glGenFramebuffersEXT(1, &id);
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, id);
if(enableDepth)
{
createDepthBuffer();
initDepthBuffer();
//choice between rendering depth into a texture or a renderbuffer
if(depthTexture)
glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, GL_TEXTURE_2D, depthTextureID, 0);
else
glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, GL_RENDERBUFFER_EXT, depthTextureID);
}
if(enableColor)
{
createColorBuffer();
initColorBuffer();
glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, colorTextureID, 0);
}
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, m_defaultWindowFramebufferID);
if(enableColor)
{
glDrawBuffer(GL_BACK);
glReadBuffer(GL_BACK);;
}
#ifdef _DEBUG
checkFBO();
#endif
initialized=true;
glDisable(GL_TEXTURE_2D);
}
else
setSize(width, height);
}
int main(int argc, char** argv)
{
if (!glfwInit()) // 初始化glfw库
{
std::cout << "Error::GLFW could not initialize GLFW!" << std::endl;
return -1;
}
// 开启OpenGL 3.3 core profile
std::cout << "Start OpenGL core profile version 3.3" << std::endl;
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);
// 创建窗口
GLFWwindow* window = glfwCreateWindow(WINDOW_WIDTH, WINDOW_HEIGHT,
"Demo of PBO(asynchronous DMA transfer)", NULL, NULL);
if (!window)
{
std::cout << "Error::GLFW could not create winddow!" << std::endl;
glfwTerminate();
return -1;
}
glfwSetWindowPos(window, 300, 100);
// 创建的窗口的context指定为当前context
glfwMakeContextCurrent(window);
// 注册窗口键盘事件回调函数
glfwSetKeyCallback(window, key_callback);
// 注册鼠标事件回调函数
glfwSetCursorPosCallback(window, mouse_move_callback);
// 注册鼠标滚轮事件回调函数
glfwSetScrollCallback(window, mouse_scroll_callback);
// 鼠标捕获 停留在程序内
glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
// 初始化GLEW 获取OpenGL函数
glewExperimental = GL_TRUE; // 让glew获取所有拓展函数
GLenum status = glewInit();
if (status != GLEW_OK)
{
std::cout << "Error::GLEW glew version:" << glewGetString(GLEW_VERSION)
<< " error string:" << glewGetErrorString(status) << std::endl;
glfwTerminate();
return -1;
}
// 设置视口参数
glViewport(0, 0, WINDOW_WIDTH, WINDOW_HEIGHT);
// Section1 准备顶点数据
setupQuadVAO();
preparePBO();
initColorBuffer();
// Section2 加载字体
FontResourceManager::getInstance().loadFont("arial", "../../resources/fonts/arial.ttf");
FontResourceManager::getInstance().loadASCIIChar("arial", 38, unicodeCharacters);
// Section3 加载纹理
cubeTextId = TextureHelper::load2DTexture("../../resources/textures/wood.png");
initPixelText();
// Section4 准备着色器程序
Shader shader("scene.vertex", "scene.frag");
Shader textShader("text.vertex", "text.frag");
glEnable(GL_DEPTH_TEST);
glEnable(GL_CULL_FACE);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
// 开始游戏主循环
while (!glfwWindowShouldClose(window))
{
GLfloat currentFrame = (GLfloat)glfwGetTime();
deltaTime = currentFrame - lastFrame;
lastFrame = currentFrame;
glfwPollEvents(); // 处理例如鼠标 键盘等事件
do_movement(); // 根据用户操作情况 更新相机属性
// 清除颜色缓冲区 重置为指定颜色
glClearColor(0.18f, 0.04f, 0.14f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glm::mat4 projection;
glm::mat4 view;
glm::mat4 model;
// 这里填写场景绘制代码
// 先绘制纹理图片
shader.use();
glUniformMatrix4fv(glGetUniformLocation(shader.programId, "projection"),
1, GL_FALSE, glm::value_ptr(projection));
glUniformMatrix4fv(glGetUniformLocation(shader.programId, "view"),
1, GL_FALSE, glm::value_ptr(view));
model = glm::mat4();
glUniformMatrix4fv(glGetUniformLocation(shader.programId, "model"),
1, GL_FALSE, glm::value_ptr(model));
if (!isFirstRendered)
{
renderInitScene(shader);
isFirstRendered = true;
}
else
{
renderScene(shader);
}
// 在右侧绘制信息文字 否则左侧文字会复制到右侧
textShader.use();
projection = glm::ortho(0.0f, (GLfloat)(SINGLE_SCREEN_WIDTH),
0.0f, (GLfloat)SINGLE_SCREEN_HEIGHT);
view = glm::mat4();
glUniformMatrix4fv(glGetUniformLocation(textShader.programId, "projection"),
1, GL_FALSE, glm::value_ptr(projection));
glUniformMatrix4fv(glGetUniformLocation(textShader.programId, "view"),
1, GL_FALSE, glm::value_ptr(view));
model = glm::mat4();
glUniformMatrix4fv(glGetUniformLocation(textShader.programId, "model"),
1, GL_FALSE, glm::value_ptr(model));
renderInfo(textShader);
printTransferRate();
glBindVertexArray(0);
glUseProgram(0);
glfwSwapBuffers(window); // 交换缓存
}
// 释放资源
glDeleteVertexArrays(1, &quadVAOId);
glDeleteBuffers(1, &quadVBOId);
glDeleteVertexArrays(1, &textVAOId);
glDeleteBuffers(1, &textVBOId);
glDeleteBuffers(2, PBOIds); // 注意释放PBO
releaseColorBuffer();
glfwTerminate();
return 0;
}
