opengl制作天空盒-编程知识

opengl制作天空盒

首先创建顶点数组

unsigned int m_uiVaoBufferID;
glGenVertexArrays(1, &m_uiVaoBufferID);

然后创建顶点缓冲区

    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};unsigned int m_uiVboBufferID;
glGenBuffers(1, &m_uiVboBufferID);
glBindBuffer(GL_ARRAY_BUFFER, m_uiVboBufferID);
glBufferData(GL_ARRAY_BUFFER, sizeof(skyboxVertices), skyboxVertices, GL_STATIC_DRAW);
glEnableVertexAttribArray(0))
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3*sizeof(float), 0);

创建并编译shader（这里我将编译shader封装成了类，通用的用法）

m_pShaderObject = new CShaderObject("/res/shaders/skybox.shader", m_pOpenglParent);

创建纹理

glGenTextures(1, &m_uiBufferID);
glBindTexture(GL_TEXTURE_CUBE_MAP, m_uiBufferID);std::vector<std::string> strFilePathVector = {"/res/textures/skybox2/cube_+x.png","/res/textures/skybox2/cube_-x.png","/res/textures/skybox2/cube_+y.png","/res/textures/skybox2/cube_-y.png","/res/textures/skybox2/cube_+z.png","/res/textures/skybox2/cube_-z.png",
};int iWidth, iHeight, iBpp;
for(unsigned int i=0; i<strFilePathVector.size(); i++){stbi_set_flip_vertically_on_load(0);unsigned char* data = stbi_load(strFilePathVector.at(i).c_str(), &iWidth, &iHeight, &iBpp, 0);glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, \GL_RGB, iWidth, iHeight, 0, \GL_RGB, GL_UNSIGNED_BYTE, data);if(data){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);
glBindTexture(GL_TEXTURE_CUBE_MAP, 0);

我们把下述全景图片进行切割后载入到程序中