OpenGL get default depthbuffer

Question

I have an application that uses only the default opengl framebuffer. It is initialized with color and depth buffer. I want to use the depth buffer as a uniform within a shader to access the current depth values. How can I make this happen? I tried to get the GLint ID of the depth buffer with the following command:

GLint params;
glGetFramebufferAttachmentParameteriv(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME, &params);
std::cout << "Depthbuffer id:" << params << std::endl;

the output is something like 325462352776. so that doesn't work :(

How can I get the correct ID of the depth buffer so I can use it to read its values in a shader?

Answer 1

Components of the default framebuffer do not have an "ID". You can only use those images as components of the default framebuffer.

If you want to use images in a framebuffer as textures or the like, then you're going to have to create them yourself. You cannot rely on the default framebuffer's images.