我想将 opengl 主帧缓冲区复制到一个 fbo,它附加两个纹理对象。然后我想将颜色缓冲区和深度缓冲区传输到两个纹理对象。我使用glbiltframebuffer,但纹理是黑色的,正确的方法是什么?我的代码:
// Create the FBO
glGenFramebuffers(1, &m_fbo);
glBindFramebuffer(GL_DRAW_FRAMEBUFFER, m_fbo);
// Create textures
glGenTextures(1, &m_colorTexture);
glGenTextures(1, &m_depthTexture);
// color texture
glBindTexture(GL_TEXTURE_2D, m_colorTexture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, Width, Height, 0, GL_RGB, GL_FLOAT, NULL);
glFramebufferTexture2(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, m_colorTexture, 0);
// depth texture
glBindTexture(GL_TEXTURE_2D, m_depthTexture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT24, Width, Height, 0, GL_DEPTH_COMPONENT, GL_FLOAT, NULL);
glBindTexture(GL_TEXTURE_2D, 0);
glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, m_depthTexture, 0);
GLenum Status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
if (Status != GL_FRAMEBUFFER_COMPLETE) {
printf("error, status: 0x%x\n", Status);
return false;
}
// restore default FBO
glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
//copy the main framebuffer to FBO
glBindFramebuffer(GL_READ_FRAMEBUFFER, 0);
glBindFramebuffer(GL_DRAW_FRAMEBUFFER, m_fbo);
glBlitFramebuffer(0, 0, Width, Height, 0, 0, Width, Height, GL_COLOR_BUFFER_BIT, GL_NEAREST);
glBindFramebuffer(GL_READ_FRAMEBUFFER, 0);
glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
GLenum error = glGetError();
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