The goal: allow to easily use AO approximation in scenes which combines
both small and large scale objects.
The idea: use per-object AO distance which will allow to override world
settings. Instancer object will "propagate" its AO distance to all its
instances unless the instance defines own distance (this allows to
modify AO distance in the shot files, without requiring to modify props
used in the shots.
Available from the new Fats GI Approximation panel in object properties.
Differential Revision: https://developer.blender.org/D12112
WITH_CYCLES_DEBUG was used for rendering BVH debugging passes. But since we
mainly use Embree an OptiX now, this information is no longer important.
WITH_CYCLES_DEBUG_NAN will enable additional checks for NaNs and invalid values
in the kernel, for Cycles developers. Previously these asserts where enabled in
all debug builds, but this is too likely to crash Blender in scenes that render
fine regardless of the NaNs. So this is behind a CMake option now.
Fixes T90240
This fixes a performance regression on Ampere cards, on specific scenes like
classroom. For cycles-x there is little difference, but this is still helpful
for LTS releases, and we need to upgrade at some point anyway.
Custom properties defined on objects are not accessible from the
attribute node when rendering a volume in Cycles. This is because
this case is not handled.
To handle it, added a primitive type for volumes in the kernel,
which is then used in the initialization of ShaderData and to
check whether an attribute lookup is for a volume.
`volume_attribute_float4` is also now checking the attribute
element type to dispatch to the right lookup function.
Reviewed By: #cycles, brecht
Maniphest Tasks: T87194
Differential Revision: https://developer.blender.org/D11728
Offset rays from the flat surface to match where they would be for a smooth
surface as specified by the normals. In the shading panel there is now a
Shading Offset (existing option) and Geometry Offset (new).
The Geometry Offset works as follows:
* 0: disabled
* 0.001: only terminated triangles (normal points to the light, geometry
doesn't) are affected
* 0.1 (default): triangles at grazing angles are affected, and the effect
fades out
* 1: all triangles are affected
Limitations:
* The artifact is still visible in some cases, it could be that some quads
require to be treated specifically as quads.
* Inconsistent normals cause artifacts.
* If small objects cast shadows to a big low poly surface, the shadows can
appear to be in a wrong place - because the surface moved slightly above
the geometry. This can be noticed only at grazing angles to light.
* Approximated surfaces of two non-intersecting low-poly objects can overlap
that causes off-the-wall shadows.
Generally, using one or a few levels of subdivision can get rid of artifacts
faster than before.
Differential Revision: https://developer.blender.org/D11065
Cycles, Eevee, OSL, Geo, Attribute
This operator provides consistency with the standard math node. Allows users to use a single node instead of two nodes for this common operation.
Reviewed By: HooglyBoogly, brecht
Differential Revision: https://developer.blender.org/D10808
Both before and after can have artifacts with some normal maps, but this seems to give
worse artifacts on average which are not worth the minor performance increase.
This reverts commit 21bc1a99ba.
Ref T88368, D10084
These seem to be causing some stability issues, and really are just not that
useful in practice. Compiling them is slow already, so it does not improve
the user experience much to show an AO preview if it's not nearly instant.
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
For indirect light rays, don't assume any hit is opaque, rather if it has
transparency or emission do the shading but don't do any further bounces.
Naturally this is slower when there are transparent surfaces, however
without this cutout opacity doesn't give sensible results.
Differential Revision: https://developer.blender.org/D10985
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
Cycles, Eevee, OSL, Geo, Attribute
Based on outdated refract patch D6619 by @cubic_sloth
`refract` and `faceforward` are standard functions in GLSL, OSL and Godot shader languages.
Adding these functions provides Blender shader artists access to these standard functions.
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D10622
This is an implementation that is about 1.5-2.1 times faster. It gives a result
that is on average 6° different from the old implementation. The difference is
because normals (Ng, N, N') are not selected to be coplanar, but instead
reflection R is lifted the least amount and the N' is computed as a bisector.
Differential Revision: https://developer.blender.org/D10084
Offset the starting point of segments by a random amount to avoid the bounding
box shape affecting the result and creating artifacts.
Differential Revision: https://developer.blender.org/D10576
Something in this update broke the floor() function in CUDA, instead use
floorf() like we do everywhere else in the kernel code. Thanks to Ray
Molenkamp for identifying the solution.
