在learnopengl.com的教程中,关于漫反射辐照度的部分涉及到captureViews,这是一个用于捕获场景的函数,并将其存储在一个立方体贴图中的过程。
以下是一个示例代码,演示如何使用captureViews函数来捕获场景并生成立方体贴图:
// 创建一个立方体贴图的帧缓冲对象
unsigned int captureFBO;
glGenFramebuffers(1, &captureFBO);
glBindFramebuffer(GL_FRAMEBUFFER, captureFBO);
// 创建一个立方体贴图的纹理对象
unsigned int captureCubeMap;
glGenTextures(1, &captureCubeMap);
glBindTexture(GL_TEXTURE_CUBE_MAP, captureCubeMap);
for (unsigned int i = 0; i < 6; ++i)
{
// 将立方体贴图的每个面作为帧缓冲对象的颜色附件
glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, GL_RGB16F, captureSize, captureSize, 0, GL_RGB, GL_FLOAT, nullptr);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, captureCubeMap, 0);
}
// 创建一个深度缓冲对象,并将其作为帧缓冲对象的深度附件
unsigned int captureRBO;
glGenRenderbuffers(1, &captureRBO);
glBindRenderbuffer(GL_RENDERBUFFER, captureRBO);
glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT24, captureSize, captureSize);
glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, captureRBO);
// 检查帧缓冲对象是否完整
if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
{
std::cout << "Framebuffer is not complete!" << std::endl;
}
// 设置视口大小为立方体贴图的大小
glViewport(0, 0, captureSize, captureSize);
// 渲染场景的六个方向,捕获每个方向的场景贴图
for (unsigned int i = 0; i < 6; ++i)
{
// 设置捕获视图的投影矩阵和视图矩阵
glm::mat4 captureProjection = glm::perspective(glm::radians(90.0f), 1.0f, 0.1f, 10.0f);
glm::mat4 captureViews[] =
{
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(1.0f, 0.0f, 0.0f), glm::vec3(0.0f, -1.0f, 0.0f)),
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(-1.0f, 0.0f, 0.0f), glm::vec3(0.0f, -1.0f, 0.0f)),
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(0.0f, 1.0f, 0.0f), glm::vec3(0.0f, 0.0f, 1.0f)),
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(0.0f, -1.0f, 0.0f), glm::vec3(0.0f, 0.0f, -1.0f)),
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(0.0f, 0.0f, 1.0f), glm::vec3(0.0f, -1.0f, 0.0f)),
glm::lookAt(glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(0.0f