These should not have any effect on render results, except in some cases with
you have overlapping faces, where the noise seems to be slightly reduced.
There are some performance improvements, for simple scenes I wouldn't expect
more than 5-10% to be cut off the render time, for sintel scenes we got about
50% on average, that's with millions of polygons on intel quad cores. This
because memory access / cache misses were the main bottleneck for those scenes,
and the optimizations improve that.
Interal changes:
* Remove RE_raytrace.h, raytracer is now only used by render engine again.
* Split non-public parts rayobject.h into rayobject_internal.h, hopefully
makes it clearer how the API is used.
* Added rayintersection.h to contain some of the stuff from RE_raytrace.h
* Change Isect.vec/labda to Isect.dir/dist, previously vec was sometimes
normalized and sometimes not, confusing... now dir is always normalized
and dist contains the distance.
* Change VECCOPY and similar to BLI_math functions.
* Force inlining of auxiliary functions for ray-triangle/quad intersection,
helps a few percentages.
* Reorganize svbvh code so all the traversal functions are in one file
* Don't do test for root so that push_childs can be inlined
* Make shadow a template parameter so it doesn't need to be runtime checked
* Optimization in raytree building, was computing bounding boxes more often
than necessary.
* Leave out logf() factor in SAH, makes tree build quicker with no
noticeable influence on raytracing on performance?
* Set max childs to 4, simplifies traversal code a bit, but also seems
to help slightly in general.
* Store child pointers and child bb just as fixed arrays of size 4 in nodes,
nearly all nodes have this many children, so overall it actually reduces
memory usage a bit and avoids a pointer indirection.
* Division by zero fix for TNT SVD code.
* Sound fix, in case ffmpeg decode fails, don't use the samples.
* Fix for incorrect bounds of transformed objects in new raytracing code.
* Gave memory arena's a name used for allocations for easier memory
usage debugging.
* Dupligroup no_draw option was using layers but not restrict view/render
setting. (not a bugfix exactly but would do display list context switching
while drawing for no reason).
* Fix objects instanced on hair particles not giving consistent results
when the object is transformed.
* New math functions: madd_v4_v4fl, len_squared_v3v3, interp_v4_v4v4v4,
mul_v4_m4v4, SH and form factor functions, box_minmax_bounds_m4.
* mul_m4_m4m4 and mul_m3_m3m3 now accept the same pointers for multiple
arguments.
* endjob callback for WM jobs system.
* Geometry node uv/color layer now has search list/autocomplete.
* Various small buildsystem tweaks, not strictly needed yet in trunk.
* mingw almost compiles again cleanly, except for a linking error when linking blender http://www.pasteall.org/8297
* win64 should compile again too to a similar degree?
* silenced warnings about no newlines...
(this is a generalization of some of the experimental stuff i tried during SoC,
but only had time to improve a few days ago)
- it should yield slightly better results
- the cost model can somehow be tweaked to optimize for diferent trees.
*cleaned up some code
*added counters for number of SIMD BB tests
*added GPL license block on missing files
