This is the first of a sequence of changes to support compiling Cycles kernels as MSL (Metal Shading Language) in preparation for a Metal GPU device implementation.
MSL requires that all pointer types be declared with explicit address space attributes (device, thread, etc...). There is already precedent for this with Cycles' address space macros (ccl_global, ccl_private, etc...), therefore the first step of MSL-enablement is to apply these consistently. Line-for-line this represents the largest change required to enable MSL. Applying this change first will simplify future patches as well as offering the emergent benefit of enhanced descriptiveness.
The vast majority of deltas in this patch fall into one of two cases:
- Ensuring ccl_private is specified for thread-local pointer types
- Ensuring ccl_global is specified for device-wide pointer types
Additionally, the ccl_addr_space qualifier can be removed. Prior to Cycles X, ccl_addr_space was used as a context-dependent address space qualifier, but now it is either redundant (e.g. in struct typedefs), or can be replaced by ccl_global in the case of pointer types. Associated function variants (e.g. lcg_step_float_addrspace) are also redundant.
In cases where address space qualifiers are chained with "const", this patch places the address space qualifier first. The rationale for this is that the choice of address space is likely to have the greater impact on runtime performance and overall architecture.
The final part of this patch is the addition of a metal/compat.h header. This is partially complete and will be extended in future patches, paving the way for the full Metal implementation.
Ref T92212
Reviewed By: brecht
Maniphest Tasks: T92212
Differential Revision: https://developer.blender.org/D12864
For details see the "Extending the Disney BRDF to a BSDF with Integrated
Subsurface Scattering" paper.
We split the diffuse BSDF into a lambertian and retro-reflection component.
The retro-reflection component is always handled as a BSDF, while the
lambertian component can be replaced by a BSSRDF.
For the BSSRDF case, we compute Fresnel separately at the entry and exit
points, which may have different normals. As the scattering radius decreases
this converges to the BSDF case.
A downside is that this increases noise for subsurface scattering in the
Principled BSDF, due to some samples going to the retro-reflection component.
However the previous logic (also in 2.93) was simple wrong, using a
non-sensical view direction vector at the exit point. We use an importance
sampling weight estimate for the retro-reflection to try to better balance
samples between the BSDF and BSSRDF.
Differential Revision: https://developer.blender.org/D12801
There is not enough time before the release to improve Random Walk to handle
all cases this was used for, so restore it for now.
Since there is no more path splitting in cycles-x, this can increase noise in
non-flat areas for the sample number of samples, though fewer rays will be traced
also. This is fundamentally a trade-off we made in the new design and why Random
Walk is a better fit. However the importance resampling we do now does help to
reduce noise.
Differential Revision: https://developer.blender.org/D12800
Previously the storage here was optimized to avoid indirections in BVH2
traversal. This helps improve performance a bit, but makes performance
and memory usage of Embree and OptiX BVHs a bit worse also. It also adds
code complexity in other parts of the code.
Now decouple triangle and curve primitive storage from BVH2.
* Reduced peak memory usage on all devices
* Bit better performance for OptiX and Embree
* Bit worse performance for CUDA
* Simplified code:
** Intersection.prim/object now matches ShaderData.prim/object
** No more offset manipulation for mesh displacement before a BVH is built
** Remove primitive packing code and flags for Embree and OptiX
** Curve segments are now stored in a KernelCurve struct
* Also happens to fix a bug in baking with incorrect prim/object
Fixes T91968, T91770, T91902
Differential Revision: https://developer.blender.org/D12766
Fixes:{T91064}
Caused by {rBcd118c5581f482afc8554ff88b5b6f3b552b1682}
- Applies `ensure_valid_reflection()` to the normal input on all BSDFs for CPU and GPU.
- This doesn't affect hair.
- Removes `ensure_valid_reflection()` from the output of Bump Map and Normal Map nodes for CPU/GPU as it is not needed.
- The fix doesn't touch OSL.
Reviewed By: brecht, leesonw
Maniphest Tasks: T91064
Differential Revision: https://developer.blender.org/D12403
This effectively undoes some of the following commit:
rB4537e8558468c71a03bf53f59c60f888b3412de2
The tables in question were duplicated 5-6 times into the blender
executable due to the headers being used in multiple translation units.
This contributes ~6.3kb worth of duplicate data into the binary.
Some further details are in the below revision.
Differential Revision: https://developer.blender.org/D12724
Goal is to add the length attribute to the Hair Info node, for better control over color gradients or similar along the hair.
Reviewed By: #eevee_viewport, brecht
Differential Revision: https://developer.blender.org/D10481
This includes much improved GPU rendering performance, viewport interactivity,
new shadow catcher, revamped sampling settings, subsurface scattering anisotropy,
new GPU volume sampling, improved PMJ sampling pattern, and more.
Some features have also been removed or changed, breaking backwards compatibility.
Including the removal of the OpenCL backend, for which alternatives are under
development.
Release notes and code docs:
https://wiki.blender.org/wiki/Reference/Release_Notes/3.0/Cycleshttps://wiki.blender.org/wiki/Source/Render/Cycles
Credits:
* Sergey Sharybin
* Brecht Van Lommel
* Patrick Mours (OptiX backend)
* Christophe Hery (subsurface scattering anisotropy)
* William Leeson (PMJ sampling pattern)
* Alaska (various fixes and tweaks)
* Thomas Dinges (various fixes)
For the full commit history, see the cycles-x branch. This squashes together
all the changes since intermediate changes would often fail building or tests.
Ref T87839, T87837, T87836
Fixes T90734, T89353, T80267, T80267, T77185, T69800
Prior to rBb8ecdbcd964a normals were stored both in
DeviceScene.tri_vnormal and the float3 attributes buffer. However, the
normals in `DeviceScene.tri_vnormal` might have be transformed to world
space if the object's transformation was applied, while the data in the
float3 attributes buffer were not. This caused shading issues in cases
where the objects did have transformation applied, as the math expects
the normals to be in object space.
To fix this, convert the normals to object space if necessary before
applying the normal map.
Reviewed By: brecht
Maniphest Tasks: T90854
Differential Revision: https://developer.blender.org/D12294
This modifies the attribute lookup to use object coordinates if no
generated coordinates are found on the geometry.
This is useful to avoid creating and copying this attribute, thus saving
a bit of time and memory.
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D12238
Vertex normals are needed for normals maps and therefore are packed and send
to the device alongside the other float3 attributes. However, we already pack
and send vertex normals through `DeviceScene.tri_vnormal`.
This removes the packing of vertex normals from the attributes buffer, and
reuses `tri_vnormal` in the kernel for normals lookup for normal maps, which
reduces memory usage a bit, and speeds up device updates.
This also fixes potential missing normals updates following rB12a06292af86,
since the need for vertex normals for normals maps was overlooked.
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D12237
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
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
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
Specular color is set to black instead of white inside the Principled BSDF
when the base color is set to fully black. This is contradictory to the sample
code of the Disney BRDF in BRDF Explorer. This patch aligns both
implementations.
Differential Revision: https://developer.blender.org/D10448
Support for the AO and bevel shader nodes requires calling "optixTrace" from within the shading
VM, which is only allowed from inlined functions to the raygen program or callables. This patch
therefore converts the shading VM to use direct callables to make it work. To prevent performance
regressions a separate kernel module is compiled and used for this purpose.
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D9733
The Normal Map node was falling back to (0, 0, 0) when it was missing
the required attributes to calculate a new normal.
(0, 0, 0) is not a valid normal and can lead to NaNs when it is
normalized later in the shader. Instead, we now return sd->N,
the unperturbed surface normal.
This avoids OpenCL inlining heavy volume interpolation code once for every
data type, which could cause a performance regression when we add a float4
data type in the next commit.
Ref D2057
Corrects incorrect usage of contraction for 'it is', when possessive 'its' was required.
Differential Revision: https://developer.blender.org/D9250
Reviewed by Campbell Barton
The current 1D Voronoi implementation for the Distance to Edge option
computes the distance to the cells instead. This patch fixes that and
compute the distance to the edge.
Reviewed By: JacquesLucke, brecht
Differential Revision: https://developer.blender.org/D8634
The sky will appear brighter than before by default. To compensate for this,
lower exposure in the Film panel. The default altitude was also changed from
90 to 15 degrees.
Patch contributed by Marco with the help of Ryan Jones.
Differential Revision: https://developer.blender.org/D8285
The problem here was numerical precision: The code calculates the angle between
sun and view direction, and the usual acos(dot(a, b)) approach for that has
poor numerical performance for almost parallel angles.
As a result, the generally tiny difference between floating point computation
between CPU and GPU was enough to make the sun vanish at different radii,
causing different results.
The new version fixes the difference by making the computation much more robust
on both platforms.
The kernel did not work correctly when these were disabled anyway. The
optimized BVH traversal for the no instances case was also only used on
the CPU, so no longer makes sense to keep.
Ref T73778
Depends on D8010
Maniphest Tasks: T73778
Differential Revision: https://developer.blender.org/D8011
The hair BSDFs are already designed to assume this, and disabling backface
culling would break them in some cases.
Ref T73778
Depends on D8009
Maniphest Tasks: T73778
Differential Revision: https://developer.blender.org/D8010
This commit adds a new model to the Sky Texture node, which is based on a
method by Nishita et al. and works by basically simulating volumetric
scattering in the atmosphere.
By making some approximations (such as only considering single scattering),
we get a fairly simple and fast simulation code that takes into account
Rayleigh and Mie scattering as well as Ozone absorption.
This code is used to precompute a 512x128 texture which is then looked up
during render time, and is fast enough to allow real-time tweaking in the
viewport.
Due to the nature of the simulation, it exposes several parameters that
allow for lots of flexibility in choosing the look and matching real-world
conditions (such as Air/Dust/Ozone density and altitude).
Additionally, the same volumetric approach can be used to compute absorption
of the direct sunlight, so the model also supports adding direct sunlight.
This makes it significantly easier to set up Sun+Sky illumination where
the direction, intensity and color of the sun actually matches the sky.
In order to support properly sampling the direct sun component, the commit
also adds logic for sampling a specific area to the kernel light sampling
code. This is combined with portal and background map sampling using MIS.
This sampling logic works for the common case of having one Sky texture
going into the Background shader, but if a custom input to the Vector
node is used or if there are multiple Sky textures, it falls back to using
only background map sampling (while automatically setting the resolution to
4096x2048 if auto resolution is used).
More infos and preview can be found here:
https://docs.google.com/document/d/1gQta0ygFWXTrl5Pmvl_nZRgUw0mWg0FJeRuNKS36m08/view
Underlying model, implementation and documentation by Marco (@nacioss).
Improvements, cleanup and sun sampling by @lukasstockner.
Differential Revision: https://developer.blender.org/D7896
Since the sampling and evaluation functions handle both cases anyways,
there's not really a point for keeping the distinction in the kernel,
so we might as well cut down the number of CLOSURE_BSDF_MICROFACETs a bit.
Differential Revision: https://developer.blender.org/D7736
This patch will add some compiler hints to break unrolling in the
nestled for loops of the voronoi node.
Reviewed by: Brecht van Lommel
Differential Revision: https://developer.blender.org/D7574
Currently in fractal_noise functions, each subsequent octave doubles the
frequency and reduces the amplitude by half. This patch introduces Roughness
input to Noise and Wave nodes. This multiplier determines how quickly the
amplitudes of the subsequent octaves decrease.
Value of 0.5 will be the default, generating identical noise we had before.
Values above 0.5 will increase influence of each octave resulting in more
"rough" noise, most interesting pattern changes happen there. Values below
0.5 will result in more "smooth" noise.
Differential Revision: https://developer.blender.org/D7065
This patch adds an AVX implementation of Perlin noise in Cycles.
An avxi type was also added as a utility based on the respective
type in Intel Embree.
Only 3D and 4D noise were implemented, there is no benefit for
utilizing AVX in 1D and 2D noise. The SSE trilinear interpolation
function was used in the AVX implementation because there is no
benefit from using AVX in interpolating the last three dimensions.
Differential Revision: https://developer.blender.org/D6680
