This is something which was reported to work fine by Mai, Benjamin and
confirmed by myself. Disabling this workaround gains us some speedup:
Before Now
bmw27 04:28.42 04:07.79
classroom 09:26.48 08:54.53
fishy_cat 08:44.01 08:18.70
koro 09:17.98 08:57.18
pavillon_barcelone 12:26.64 11:52.81
Test environment is:
- Ubuntu 16.04, with all updates installed
- AMD RX 480 GPU
- amdgpu pro driver version 17.10-450821
Unfortunately this means disabling the code that ensures the title
bar is properly scaled with DPI, however better to have that as a
cosmetic issue than Blender being unusable with a lot of Intel GPUs.
Some of the functions might have been inlined, but others i don't see
how that was possible (don't think virtual functions can be inlined here).
In any case, better be explicitly optimal in the code.
The problem here was that when a "invalid" path is generated by the panoramic camera, it was tagged
as RAY_TO_REGENERATE with the intention of generating a new path in kernel_buffer_update.
However, since that state was not handled in kernel_queue_enqueue, kernel_buffer_update did not
process the path which resulted in an infinite loop.
Now computers that support OpenGl3.3 (but not 4.5) can run Blender 2.8.
For any given HDC, you may only call SetPixelFormat *ONCE* any future
calls for the same HDC will fail. And computers that would support only
OpenGL 3.3 wouldn't have a change to get a valid OpenGL context because
the pixelformat was already set while trying to probe the supported
contexts.
We fix this by splitting the final context creation from the query of
supported OpenGL versions.
Patch by Ray Molenkamp (bzzt_ploink/LazyDodo) with code style fixes and
comments by me.
This avoids using GWN_vertbuf_attr_set which needs to calculate the
offset and perform a memcpy every call.
Exposing the data directly allows us to avoid a memcpy in some cases
and means we can write to the vertex buffer's memory directly.
As the title says, the normal wasn't set for the Hair BSDF because it wasn't
needed before. However, the denoiser uses it to store the feature passes, so
it needs to be set now.
Add a safe version of normalize since all uses of normalize
did zero length checks, move this into a function.
Also avoid unnecessary conversion.
Gives minor speedup here (approx 3-5%).
If there was any specularity in the Principled BSDF, it would get a sampling
weight of one regardless of its actual impact.
This commit makes Cycles estimate the contribution of the component and adjust
the weighting accordingly, which greatly improves the noise characteristics of
the Principled BSDF in many cases.
Note that this commit might slightly change the brightness of areas when using
MultiGGX and high roughnesses, but the new brightness is more accurate and
closer to the result of Branched Path Tracing. See T51836 for details.
Differential Revision: https://developer.blender.org/D2677
The PDF of the MultiGGX sampling is approximated by the singlescattering GGX
term as well as a scaled diffuse term that makes up for the energy in the
multiscattering component that's missed by GGX.
However, there were two problems with the glossy terms: The diffuse term missed
a normalization factor, and the singlescattering term was not properly scaled
down based on the albedo estimate.
The glass term was completely wrong and has been rewritten. It uses the fresnel
factor to weight reflection vs. refraction and uses the glossy MultiGGX model
for reflection.
For refraction, the correct singlescattering term is now used, and a new
albedo approximation is used that was derived by evaluating GGX albedo for
roughnesses from 0 to 1 and IORs from 1 to 3 and fitting numerical
approximations to it. The resulting model has a mean relative error of 9e-5,
but could probably be simplified without losing noticable accuracy in the
final render.
The improved PDFs help with glossy highlights (due to better light sampling vs.
closure sampling MIS) and fix the situation described in T51836 where mixing
MultiGGX with other closures (as it happens in e.g. the Principled
BSDF) causes incorrect darkening.
