Enabling floating point framebuffers with OpenGL

Anyone know how to enable floating point framebuffers with OpenGL?? The reason I want it is, because I want to have huge numbers of blending operations.

Is this even supported in OpenGL?? I am running on a GFX 5600 by the way…

Thanks in advance,

floating point buffers are only available using pbuffers through extensions.
you can’t blend using floating point buffers either. for this you need render to texture and multiple passes.