* Ashikhmin-Shirley anisotropic BSDF was added as closure
* Anisotropic BSDF node now has two distributions
Reviewers: brecht, dingto
Differential Revision: https://developer.blender.org/D549
Samples render slower than before, but hopefully this is made up for with
reduced noise in most cases. The main slowdown comes from samples that would
previously be wasted and turn out black, which are now continued.
GGX sampling is about the same speed as before, while for Beckmann it is slower
still. Perhaps optimizations are still possible there, but didn't find anything
easy.
Code from this paper, which comes with sample code:
Importance Sampling Microfacet-Based BSDFs using the Distribution of Visible Normals.
E. Heitz and E. d'Eon, EGSR 2014
Differential Revision: https://developer.blender.org/D572
This gives you "Multiple Importance", "Distance" and "Equiangular" choices.
What multiple importance sampling does is make things more robust to certain
types of noise at the cost of a bit more noise in cases where the individual
strategies are always better.
So if you've got a pretty dense volume that's lit from far away then distance
sampling is usually more efficient. If you've got a light inside or near the
volume then equiangular sampling is better. If you have a combination of both,
then the multiple importance sampling will be better.
* Volume multiple importace sampling support to combine equiangular and distance
sampling, for both homogeneous and heterogeneous volumes.
* Branched path "Sample All Direct Lights" and "Sample All Indirect Lights" now
apply to volumes as well as surfaces.
Implementation note:
For simplicity this is all done with decoupled ray marching, the only case we do
not use decoupled is for distance only sampling with one light sample. The
homogeneous case should still compile on the GPU because it only requires fixed
size storage, but the heterogeneous case will be trickier to get working.
* Added support for uchar4 attributes to Cycles' attribute system.
* This is used for Vertex Colors now, which saves some memory (4 unsigned characters, instead of 4 floats).
* GPU Texture Limit on sm_20 and sm_21 decreased from 95 to 94, because we need a new texture for the uchar4 attributes. This is no problem for sm_30 or newer.
Part of my GSoC 2014.
This kernel is compiled with AVX2, FMA3, and BMI compiler flags. At the moment only Intel Haswell benefits from this, but future AMD CPUs will have these instructions as well.
Makes rendering on Haswell CPUs a few percent faster, only benchmarked with clang on OS X though.
Part of my GSoC 2014.
Instead of pre-calculation and storage, we now calculate the face normal during render.
This gives a small slowdown (~1%) but decreases memory usage, which is especially important for GPUs,
where you have limited VRAM.
Part of my GSoC 2014.
This makes the code a bit easier to understand, and might come in handy
if we want to reuse more Embree code.
Differential Revision: https://developer.blender.org/D482
Code by Brecht, with fixes by Lockal, Sergey and myself.
This gives around 30% of speedup for gaussian blur node.
Pretty much straightforward implementation inside the node
itself, but needed to implement some additional things:
- Aligned malloc. It's needed to load data onto SSE registers
faster. based on the aligned_malloc() from Libmv with
some additional trickery going on to support arbitrary
alignment (this magic is needed because of MemHead).
In the practice only 16bit alignment is supported because
of the lack of aligned malloc with arbitrary alignment
for OSX. Not a bit deal for now because we need 16 bytes
alignment at this moment only. Could be tweaked further
later.
- Memory buffers in compositor are now aligned to 16 bytes.
Should be harmless for non-SSE cases too. just mentioning.
Reviewers: campbellbarton, lukastoenne, jbakker
Reviewed By: campbellbarton
CC: lockal
Differential Revision: https://developer.blender.org/D564
This means packed images and movies are now supported when using OSL
backend for material shading.
Uses special file name to distinguish whether image is builtin or not.
This part might become a bit smarted or optimized a bit, but it's good
enough with this implementation already.
Suggestion by Andy Davies (metalliandy) to conform with industry standard (custom cage is something else apparently)
Note: this is the last bake related commit I plan for 2.71/rc (unless
everyone agrees that we could squeeze in D546 - custom UVs, which would
be really nice to add for 2.71 scripters)
Note 2: I'll update the wiki docs shortly
There is a new option to select whether you want to use cage or not.
When not using cage the results will be more similar with Blender
Internal, where the inwards rays (trying to hit the highpoly objects)
don't always come from smooth normals. So if the active object has sharp
edges and an EdgeSplit modifier you get bad corners.
This is useful, however, to bake to planes without the need of adding
extra loops around the edges.
When cage is "on" the user can decide on setting a cage extrusion or to
pick a Custom Cage object. The cage extrusion option works in a
duplicated copy of the active object with EdgeSplit modifiers removed to
inforce smooth normals. The custom cage option takes an object with the
same number of faces as the active object (and the same face ordering).
The custom cage now controls the direction and the origin of the
rays casted to the highpoly objects. The direction is a ray from the
point in the cage mesh to the equivalent point to the base mesh. That
means the face normals are entirely ignored when using a cage object.
For developers:
When using an object cage the ray is calculated from the cage mesh to
the base mesh. It uses the barycentric coordinate from the base mesh UV,
so we expect both meshes to have the same primitive ids (which won't be
the case if the cage gets edited in a destructive way).
That fixes T40023 (giving the expected result when 'use_cage' is false).
Thanks for Andy Davies (metalliandy) for the consulting with normal
baking workflow and extensive testing. His 'stress-test' file will be
added later to our svn tests folder. (The file itself is not public yet
since he still has to add testing notes to it).
Many thanks for the reviewers.
More on cages:
http://wiki.polycount.com/NormalMap/#Working_with_Cages
Reviewers: campbellbarton, sergey
CC: adriano, metalliandy, brecht, malkavian
Differential Revision: https://developer.blender.org/D547
Now baking does one AA sample at a time, just like final render. There is
also some code for shader antialiasing that solves T40369 but it is disabled
for now because there may be unpredictable side effects.
Cycles expects to find all node sockets with their correct names, but
this can be changed via the API (see bug report discussion).
Solution for now is to let cycles accept this case gracefully instead
of crashing. The shader will simply use the internal default values for
inputs and any connections will be ignored.
Would be nice to report the error somewhere, but cycles doesn't have a
proper logging system for this purpose yet.
it's possible that runtime optimizer would call get_attribute
with NULL renderstate. As per documentation, it's valid to
return false in that cases and in worst case we'll just miss
some possible optimization.
Supporting such cases would require some bigger changes to
Cycles since attributes are only set to up for the kernel
after shader compilation.
Thanks Brecht for review!
Transparent objects could become subtly visible by the different sampling
patterns for pixels covered and not covered by the object. It still converged
to the right solution but that can take a while. Now we try to use the same
sampling pattern here.
This reverts commit 12abe94de8.
After a long discussion in the bug tracker we decided baking should use
the faces normals for glossy (and combined). This is what Blender
Internal is doing, and one of the more predictable way of yielding
predictable results.
That also means the result will not match the render perfectly, but this
is preferrable over the alternatives at hand.
Conflicts:
intern/cycles/kernel/kernel_bake.h
