It is per-material setting which could be found under the Volume settings
in the material and world context buttons.
There could still be some code-wise improvements, like using variable-size
macro for interp3d instead of having interp3d_ex to which you can pass the
interpolation method.
This is the first step towards supporting cubic interpolation for voxel
data (such as smoke and fire). It is not epxosed to the interface at all
yet, this is to be done soon after this change.
This is so-called GPU limitation boundary hit, told compiler to NOT include
volume bound function, otherwise some real weird things used to happen.
We actually might want to do the same for CPU, inlining everything is not
the way to get fastest code.
Quite annoying, the same thing we do from the blender side, But as a positive
side we can get rid of some utf8/utf16 conversions.
Hopefully it all work fine now, at leats works on mu russki windoze laptop.
Also reduce number of branching and multiplications a bit by inlining the branches.
This gives an unmeasurable speedup, which is in case of BMW is about 2% here.
This gives more precise information about memory usage which might be real handy
when doing memory optimization.
It works good here for as long as i can tell but if for some reason you'll be
experiencing some weird slowdown please let me know.
Not as if it gives noticeable changes render-time, but it's just weird to
convert float4 to float 3 to just access individual x/y/z components.
Plus some compilers might be more stupid than GCC and don't optimize this
out well.
We queried the wrong value when looking for the bound 2D texture. This
is not totally robust because currently bound texture may not be a 2D
one, but this should work for now.
After discussion with cambo here we decided it's better to choose arbitrary side of the box
(in this case it's X-axis) and use image from it. That's better than doing a blackness.
P.S. This is literally a corner case anyway.
Ray actually should have infinite length, so we can detect camera in a volume
which is bigger that the far clipping of the camera.
This might also give some speedup (wouldn't expect much tho) because we don't
need to re-calculate ray direction and length after every bounce now.
basically we skip all non-volume objects now in the volume stack function.
Depending on the show it might give some percent of speedup.
Most of the speedup would be gained in the scenes when having SSS object
intersecting the volume and taking a reasonable amount of frame space.
Single precision exponent on 64bit linux tends to be order of magnitude slower
than double precision version even with single<->double precision conversion.
Some feedback in the mailing lists also suggests that logf() is also slow, but
this i didn't confirm here in the studio yet.
Depending on the shader setup it gives ~3% with the secret agent shot and up to
around 15% with the bmw scene here.
Quite straightforward change, the only annoying thing is that we can't use
indentation for include directive just because of the way headers inlineing
works for OpenCL.
Might do smarter job in path_source_replace_includes() but don't want to
spend time on this yet.
