This is giving too bright pixel values, as the sample scaling and random number
sample are wrong. The proper fix for this is complicated. It will be solved in
Cycles X, for now we disable this combination.
Contributed by Intel. On some scenes like classroom with particular integrated
GPUs this speeds up rendering 1.97x. With other benchmarks and GPUs it's
between 0.99-1.14x.
This issue originates from a missing BVH packing for visibility data
when it is modified.
To fix this, this adds update flags to the managers to carry the
modified visibility information from the Objects' modified flag to the
GeometryManager.
Another set of flags is added to determine which data need to be packed:
geometry, vertices, or visibility. Those flags are then used when
packing the primivites.
Reviewed By: brecht
Maniphest Tasks: T87929
Differential Revision: https://developer.blender.org/D11219
Was causing calculation issues later on in the kernel.
This change catches the most obvious case: missing attribute. The old
code was trying to set tangent to 0, but because it was transformed as
a normal it got converted to non-finite value. This change makes it so
that no transform is involved and 0 is written directly to the SVM
stack.
To cover all cases it will require using safe_normalize() in this node
and in the normal transform function. This is more involved change from
performance point of view, would be nice to verify whether we really want
to go this route.
I've left asserts in the BSDF allocation functions. Don't have strong
connection to them, but think they are handy and are not different from
having an assert in the path radiance checks.
Differential Revision: https://developer.blender.org/D11235
It is possible that BSDF allocation will advance pointer in the
allocation "pool" but will return null pointer if the weight is
too small.
One artist-measurable issue this change fixes is random issues
with denoising: normal pass for denoising could have accessed
non-initialized normal of a closure.
Differential Revision: https://developer.blender.org/D11230
The render session is keeping track of the scene update, which includes
kernel loading time.
This fixes negative render times reported when CUDA kernels are compiled
at runtime.
A bit fragile logic, can be re-implemented using some user-counted
scope utility classes, so that only outer-most time skip is applied.
This is done to ensure building with newer OptiX SDK releases that add new struct fields gives
deterministic results (no uninitialized fields and therefore random data is passed to OptiX).
The problem was that you could getting write access to a grid from a
`const Volume *` without breaking const correctness. I encountered this
when working on support for volumes in the bounding box node. For
geometry nodes there is an important distinction between getting data
"for read" and "for write", with the former returning a `const` version
of the data.
Also, for volumes it was necessary to cast away const, since all of
the relevant functions in `volume.cc` didn't have const versions. This
patch adds `const` in these places, distinguising between "for read"
and "for write" versions of functions where necessary.
The downside is that loading and unloading in the global volume cache
needs const write-access to some member variables. I see that as an
inherent problem that comes up with caching that never has a beautiful
solution anyway.
Some of the const-ness could probably be propogated futher in EEVEE
code, but I'll leave that out, since there is another level of caching.
Differential Revision: https://developer.blender.org/D10916
For Cycles, when enabling the Persistent Data option, the full render data
will be preserved from frame-to-frame in animation renders and between
re-renders of the scene. This means that any modifier evaluation, BVH
building, OpenGL vertex buffer uploads, etc, can be done only once for
unchanged objects. This comes at an increased memory cost.
Previously there option was named Persistent Images and had a more limited
impact on render time and memory.
When using multiple view layers, only data from a single view layer is
preserved to keep memory usage somewhat under control. However objects
shared between view layers are preserved, and so this can speedup such
renders as well, even single frame renders.
For Eevee and Workbench this option is not available, however these engines
will now always reuse the depsgraph for animation and multiple view layers.
This can significantly speed up rendering.
These engines do not support sharing the depsgraph between re-renders, due
to technical issues regarding OpenGL contexts. Support for this could be added
if those are solved, see the code comments for details.
* Move out of Simplify panel, into Light Paths > Fast Global Illumination
* Add separate boolan setting to enable/disable it separate from Simplify
* Default AO bounces to 1
* Put ambient occlusion distance in this panel as well
Compute a subset of the area light that actually affects the shading point
and only samples points within that.
It's not perfect as the real subset is a circle instead of a rectangle, and
the attenuation is not accounted for. However it massively reduces noise for
shading points near the area light anyway.
Ellipse shaped area lights do not have this importance sampling, but do not
have solid angle importance sampling either.
Ref D10594
This simulates the effect of a honeycomb or grid placed in front of a softbox.
In practice, it works by attenuating rays coming off-angle as a function of the
provided spread angle parameter.
Setting the parameter to 180 degrees poses no restrictions to the rays, making
the light behave the same way as before this patch.
The total light power is normalized based on the spread angle, so that the
light strength remains the same.
Differential Revision: https://developer.blender.org/D10594
The combination of building unit tests and WITH_CYCLES_NATIVE_ONLY did not
correctly detect when AVX/AVX2 support is available.
Differential Revision: https://developer.blender.org/D8201
The index_data_map was not cleared when clearing a cache, so this would just append
the new correct data to the end of the array instead of overwriting it, which would
cause us to then use outdated indices.
When the strength is initially set to zero, the shader graph is
optimized out to remove any node which will not be executed because of
this, which removes pretty much every single node, except for the
output. As the graph is empty, the world shader is made invisible to
rays so it is not evaluated in the kernel.
However, when the strength is then modified, the Background is not
updated as the modification happens on the Shader Node and not on the
Background Node, so it is never tagged as modified.
To fix this, we need to tag the Background as modified when its shader
is also modified so the Kernel data is properly updated.
Regression caused by rBbbe6d44928235cd4a5cfbeaf1a1de78ed861bb92.
Separate tile buffers on all devices only need to exist when denoising is active (so any overlap
being rendered simultaneously does not write to the same memory region).
When denoising is not active they can be distributed like all other memory when peer
memory support is available.
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D10858
As a rather premature optimization from rBbbe6d4492823, Object bounds
were only computed when either the Object or its Geometry were modified.
Prior to rB42198e9eb03b, this would work, as the Geometry was tagged as
modified if the Object's transform was also modified.
Since this tagging is not done anymore due to side effects, and since at
the time bounds are computed Objects were already processed and tag as
unmodified, the check on the modified status was always false.
For now remove this check, so the bounds are always unconditionally
updated. If this ever becomes a performance problem in large scenes with
motion blur, we will then try to find a way to nicely optimize it.
This would only affect BHV2 as OptiX and Embree handle object bounds
themselves.
