- Reduced texture I/O: Ray differentials, used to calculate texture sampling footprints, have been improved for the different ray types, which can produce dramatic speedups in scenes with large numbers of high-resolution texture maps.
- Faster bump mapping: 25% less shader evaluations per call.
- Faster ray accel build: 25% less time to build the ray acceleration structures. Memory usage and ray tracing speed are unaffected. (#3008)
- Cached of standins pointing to an .ass file: This feature can potentially save a lot of both memory and disk I/O. Because of the experimental nature of this feature, users who want to try it must manually enable it with the global option enable_procedural_cache in the User Options string field in the Render Settings.
- Bumpdiff mode in the utility shader: This mode will show how far the bump and autobump normals vary from the base smooth-shaded normals as a heatmap (blue is the same, going through green to red as varying up to 90 degrees away). This is useful for debugging the balance between subdivision iterations with displacement vs autobump making up for the rest.
- This is the first version with official Mac OS X support.
- There have been some changes to the MtoA attributes and locations as part of an UI revamp.
- aiDisplacement node has been removed.
See the latest release notes on the wiki for further details.