>> FXAA and other similar techniques are only relevant when dealing with deferred rendering only. Detecting edges on the depth buffer may sound as the solution

>> FXAA and other similar techniques are only relevant when dealing with deferred rendering only. Detecting edges on the depth buffer may sound as the solution until you realize that two planes at right angles has an edge between that can alias. The change there is in the normal and not the Z. Why do you say that FXAA is only relevant to deferred rendering? If you have a deferred rendering setup, you'll have the depth buffer and the normal buffer (a floating point texture with normal vectors) available. These can be used to do edge detection for silhouette edges and non-silhouette sharp edges. I don't know the details of modern anti aliasing techniques, but I'd guess that you can get the best edge detection using a combination of the color, depth and normal buffer. Whether you want to do this for anti aliasing is a different issue, a simple RGB edge detect may yield better results. >> Also modern graphics cards do not give programmatic access to the z-buffer as the z-buffer format is often proprietary. Deferred shading based renderers often duplicate the z-value also into a texture. This doesn't make any sense. The depth buffer may be internally stored in a compressed proprietary format, but it's still available to the programmer as a regular buffer or texture. You have plenty of ways to access the depth buffer for reading. The depth buffer can be rendered into a texture (either as floating point or regular 24 bit integer), which can be read back in a shader. You can do regular lookups where you get back the depth value or a shadow lookup with percentage closer filtering. The depth values can also be read back from the buffers (using glReadPixels in OpenGL) to be analyzed on the CPU (not feasible for anything realtime) or saved to disk or whatever.