For a long time this part of Blender has been gathering dust... based on old optimizing schedules and with sub-pixel rendering code that had small errors.

The makeover of the core anti-aliasing methods involved the following changes:

- done a full check and fixes for 100% accurate sampling

- separating old optimizing system that reduced rendering samples

- implementation of full sampling method for each sub-pixel

- removed hacks in raytracing code that bypassed the optimization

So you now can enable to have each subpixel (like 8 samples for OSA 8) to be fully rendered. This gives a relevant slowdown of the basic (scanline) rendering system. However, for more complex scenes, and especially with many small polygons and/or raytracing applied, there's a rendering speed gain possible too.

Improvements in picture quality are evident though, as samples below show. But sometimes it will require a trained eye and a magnifier though. :)

Also note that shader aliasing and texture aliasing now can be solved.

The current implementation works very nice for Gauss filter too, and works for the unified render (which doesn't have Gauss yet).

User interface

For backwards compatibility the old optimized OSA still is default for non-raytraced scenes. To enforce full sampling, you can set the "Full Osa" option in the Material Panel of the F5 menu. This works per Material, so you can exactly define when you prefer it to work.

Using ray tracing for a Material will always use the "Full Osa" however, since the optimized OSA just didn't work satisfying for it.