Seems it's just another issue with the compiler, worked around by explicitly
telling not to inline some function.
In theory we can unify this with CPU, but we're quite close to the release
so better be safe than sorry.
The following commits were supposed to add anti-alias and help with OSL
baking:
7b16fda3791b92dfa961
However they introduced other issues (artifacts mostly), see T43550 .
Leaving the code ifdef'ed for now.
This attribute missed derivatives calculation.
Not totally sure what's the proper approach for algebraic derivative
calculation, so calculating them by definition. This isn't fastest
way to do it in this case and could be replaced with some smarter magic
in the wireframe calculation loop.
At least currently implemented approach is better than nothing.
It was complaining about explicit __constant to __private memory conversion,
which is now worked around using implicit conversion.
It's not a real fix i'm afraid and i'm still failing to build OpenCL kernel
with latest Linux drivers, but maybe it'll let someone else to investigate
what causes compiler to run out of memory?
Issue was caused by the changes in 7b16fda which changed the initial
state for rng. This commit makes it so the same initial hash is used
(which solves the regression without distorting AA-looking image.
It also makes it so OpenCL compiler is happy about this code (before
this change it'll complain about trying to cast private variable to
global one).
OpenCL doesn't let you to get address of vector components, which
is kinda annoying. On the other hand, maybe now compiler will have
more chances to optimize something out.
It could have happened with really long rays and small steps.
Step size will be adjusted to the clamped number of steps in order
to preserve render result compatibility as much as possible.
We should probably reformulate this a bit, so it will give the
same looking results without step tweaks. But this new behavior
should already be much better that it was before.
This attribute means how "pointy" the geometry surface is, which allows to do
effects like dirt maps and wear-off effects on render geometry. This means the
attribute is calculated for the final mesh which means no baking (which implies
UV unwrap) is needed. Apart from this the behavior is quite close to how vertex
dirty colors works.
The new attribute is available as an output socket of Geometry node.
There's no penalty for the render time, only some delay on scene preparation
(the delay is linear of the mesh complexity).
Reviewers: brecht, juicyfruit
Subscribers: eyecandy, venomgfx
Differential Revision: https://developer.blender.org/D1086
From more investigation of the numeric failures in the kernel it appears
the check was rather correct. But in theory it;s also needed for the motion
triangles.
The issue was caused by lack of check for whether fresnel term is actually
giving total internal reflection in refraction BSDFs. This lead to usage of
arbitrary vector of (0, 0, 0) as reflection, giving numeric issues in other
areas of the kernel.
This gives some visual changes of sharp reflection but it seems to be rather
proper now. Which also corresponds with rough glossy reflection with sharpness
set to 0.001 (previously it was totally different from sharpness of 0.0, which
is just weird).
This is the same issue T43475: SSE4 code is more robust to non-finite values
in the ray origin/direction. So for now added a check before doing BVH traversal
for pre-SSE4 CPUs.
For sure actual root of the issue is a bit different and much more tricky to
solve, especially without disturbing render results too much. Still looking
into this.
In any case, it's kinda fine to have such a check, we might later make it to be
a kernel_assert() instead of just a return.
Previous fix didn't quite work well. For some reason everything worked fine when
using native nvcc in 32bit environment, but cross-compiling from 64bit platform
it was still running out of memory.
For now just made it so all the kernels are slower on 32bit CUDA as a temporary
solution. Either it'll be solved in next CUDA releases (by dropped 32bit? =\) or
we'll find better workaround.
The issue was caused by the way how we shoot the ray to see which rays we're
inside which might start bouncing back-n-forth between two close to parallel
intersecting faces.
Real solution would be to record all the intersections when shooting the ray,
but it's kinda tricky on GPU because of needed sorting and uncertainty of
how huge intersection array should be.
For now we'll just limit number of steps in the check so in worst case we'll
have some samples not being correct which will be compensated with further
sampling. Shouldn't be an issue since probability of such a lock is quite
small actually.
Slowdown was caused by watertight intersection commit and follow-up workaorund
for compiler crash which uninlined utility function which rotates the ray.
Now it's only uninlined for sm_50 and sm_52 experimental kernels which are the
only ones which failed to compile.
Rendering still might be a bit slower but at least shouldn't be that dramatic.
The issue was caused bu the optimization in surface attributes for cases when
there's only a volume shader used. Some attributes doesn't make sense in that
case and were skipped from calculation.
However, it is possible that kernel would still try to access them (because of
the shader setup etc). Prevented an infinite loop in the kernel now, which
should not have much affect on regular renders.
It is possible that ray distance will be zero which would make intersection
refinement return NaN as the refined position which would later lead to all
sort of mathematical issues.
Don't think there are ways to improve intersection accuracy for such rays
so just return original intersection coordinate.
This should fix T43475.
TODO: Need to look into possible issues in Ashikhmin BSDF which might return
zero-length reflected/transmitted ray?
Precision of the fast functions seems to be enough in there and
since the code was heavily using inverse trigonometric functions
this change gives few percent speedup on Victor's hair.
From the tests files from ctests storage doesn't have any meaningful
difference, hair on Victor is all below 4% absolute error and only
few pixels are exceeding 1% absolute difference.
In any case, let it be as it is currently so it allows us to have
fast math file in sources for it's further evaluation and possible
usage in other areas as well.
BSDF sampler function shouldn't give labels it's not intended to do.
That said reflection shouldn't give transmission ray and transmission
give reflection ray.
Added an assert in the transmission sampling but reflection still
needs some investigation because even after recent fixes the check
for projection onto the reflected ray could give both positive and
negative values.
It shouldn't have any affect on renders just makes internal logic
consistent and unleashes an issue to be investigate further.
Hair BSDF did not have proper behavior because of non-normalized
tangent direction (which it expected to be normalized).This lead
to wrong labels being returned by the hair BSDF samplers.
Reported and nailed down by Michale (MeshLogic).
The code that fixes this was commented out, but Brecht gave the go ahead to use it even if it is not the real solution
