The NanoVDB headers are not compatible with Metal due to missing address
space qualifiers. We currently have a big patch for NanoVDB header
files, which is difficult to update for OpenVDB 11. Instead extract a
few hundred lines of code from NanoVDB to do just what we need.
Pull Request: https://projects.blender.org/blender/blender/pulls/115992
This makes the GPU tricubic implementation more efficient. The dense
grid code implemented this in terms of trilinear lookups that are
hardware accelerated, but for NanoVDB this just causes unnecessary voxel
reads. Instead match the CPU code.
Pull Request: https://projects.blender.org/blender/blender/pulls/115992
This PR fixes T39823, the sole failing unit test when running with MetalRT. It does so by implementing and binding a missing intersection handler (`__anyhit__cycles_metalrt_volume_test_tri`) which is required for `scene_intersect_volume` (as used by `integrator_volume_stack_update_for_subsurface`) to work as intended. This scene exposed the error as it uses subsurface scattering on a sphere which is intersected by volume.
Pull Request: https://projects.blender.org/blender/blender/pulls/112876
This patch updates the experimental MetalRT code path to use new [curve primitives](https://developer.apple.com/videos/play/wwdc2023/10128/) which were recently added in macOS 14. This replaces the previous custom box intersection implementation, allowing the driver to better optimise curve acceleration structures for the GPU. On existing hardware, this can speed up MetalRT renders by up to 40% for scenes that use hair / curve primitives extensively.
The MetalRT option will only be available on macOS >= 14, and requires Xcode >= 15 to build (otherwise the option will be compiled out).
Authored by Marco Giordano, Michael Jones, and Jason Fielder
---
Before / after render times (M1 Max MacBook Pro, macOS 14 beta, MetalRT enabled):
```
Custom box intersection MetalRT curve primitives Speedup
fishy_cat 111.5 80.5 1.39
koro 114.4 86.7 1.32
sinosauropteryx 291.8 279.2 1.05
spring 142.3 142.2 1.00
victor 442.7 347.7 1.27
```
---
Pull Request: https://projects.blender.org/blender/blender/pulls/111795
Use the common BVH utilities header for this.
Added a special type qualifier ccl_ray_data which is defined to ccl_private
for all platforms but Metal. On Metal it is defined to ray_data.
The tricky part is that the BVH utilities are wrapped into the Metal context
class. In some of the BVH functions the context has been already constructed,
but it wasn't done in all the callbacks.
From a quick render tests of the Junkshop benchmark scene there is no render
time difference,
No functional changes are expected.
Pull Request: https://projects.blender.org/blender/blender/pulls/111967
This patch fixes the failing shader/bevel unit test when MetalRT is enabled. The ray was being transformed into local object space even when the SD_OBJECT_TRANSFORM_APPLIED flag was set.
Pull Request: https://projects.blender.org/blender/blender/pulls/107292
This patch replaces `dispatchThreadgroups` with `dispatchThreads` which takes care of non-uniform threadgroup bounds. This allows us to remove the bounds guards in the integrator kernel entry points.
Pull Request: https://projects.blender.org/blender/blender/pulls/106217
This patch fixes a MetalRT issue where viable shadow hits are discounted based on the false assumption that hits are ordered by distance. With this patch, the following unit tests now pass:
- openvdb smoke
- shadow catcher pt transparent lamp only 0.8
- shadow catcher pt transparent lamp only 1.0
Pull Request: https://projects.blender.org/blender/blender/pulls/106276
To improve mesh upload speeds and reduce the size of the scene data which allows larger scenes to be rendered.
The meshes in Cycles are currently stored as flattened meshes, where each triangle is stored as a set of 3 vertices. Unflattening writes out the vertices in a list according to the index buffer. This uses a lot of memory and for current hardware does not provide a noticeable benefit. This change unflattens the mesh by directly using the meshes vertex and index buffers directly and skips the unflattening. This change allows for larger scenes and also a reduction in the sizes of the meshes. Further it results in a decrease the amount of time it takes to upload the data to a GPU. This is especially important for when multiple GPUs are used in a single machine.
Pull Request #105173
Contributed by Yulia Kuznetcova at Apple.
NanoVDB is patched to give add address spaces required by Metal. We hope that
in the future Metal will support the generic address space.
For AMD and Intel this is currently not available since it causes a performance
regression also on scenes without volumes.
Pull Request #104837
This patch optimises subsurface intersection queries on MetalRT. Currently intersect_local traverses from the scene root, retrospectively discarding all non-local hits. Using a lookup of bottom level acceleration structures, we can explicitly query only the relevant instance. On M1 Max, with MetalRT selected, this can give a render speedup of 15-20% for scenes like Monster which make heavy use of subsurface scattering.
Patch authored by Marco Giordano.
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D17153
This patch adds two new kernels: SORT_BUCKET_PASS and SORT_WRITE_PASS. These replace PREFIX_SUM and SORTED_PATHS_ARRAY on supported devices (currently implemented on Metal, but will be trivial to enable on the other backends). The new kernels exploit sort partitioning (see D15331) by sorting each partition separately using local atomics. This can give an overall render speedup of 2-3% depending on architecture. As before, we fall back to the original non-partitioned sorting when the shader count is "too high".
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D16909
This adds a new mirror image extension type for shaders and
geometry nodes (next to the existing repeat, extend and clip
options).
See D16432 for a more detailed explanation of `wrap_mirror`.
This also adds a new sampler flag `GPU_SAMPLER_MIRROR_REPEAT`.
It acts as a modifier to `GPU_SAMPLER_REPEAT`, so any `REPEAT`
flag must be set for the `MIRROR` flag to have an effect.
Differential Revision: https://developer.blender.org/D16432
This patch generalizes the OSL support in Cycles to include GPU
device types and adds an implementation for that in the OptiX
device. There are some caveats still, including simplified texturing
due to lack of OIIO on the GPU and a few missing OSL intrinsics.
Note that this is incomplete and missing an update to the OSL
library before being enabled! The implementation is already
committed now to simplify further development.
Maniphest Tasks: T101222
Differential Revision: https://developer.blender.org/D15902
Known Issues:
- Command buffer failures when using binary archives (binary archives is disabled for Intel GPUs as a workaround)
- Wrong texture sampler being applied (to be addressed in the future)
Ref T92212
Reviewed By: brecht
Maniphest Tasks: T92212
Differential Revision: https://developer.blender.org/D16253
This patch optimises the Metal inlining policy. It gives a small speedup (2-3% on M1 Max) with no notable compilation slowdown vs what is already in master. Previously noted compilation slowdowns (as reported in T100102) were caused by forcing inlining for `ccl_device`, but we get better rendering perf by relying on compiler heuristics in these cases.
Reviewed By: brecht
Differential Revision: https://developer.blender.org/D16081
The recent revert of Apple silicon inlining changes to avoid long compile times
worked on macOS 12, but in macOS 13 Beta it results in render errors. This may
be a compiler bug and perhaps get fixed in time, but try to be on the safe side
and ensure Blender 3.3.0 works regardless.
This brings part of the inlining back, which brings improved performance but
also longer compiler times again. Compile time is around 2min now, where the
previous full inlining was about 5-7min.
Patch by Michael Jones.
Differential Revision: https://developer.blender.org/D15897
This gave a 1.1x speedup, however also leads to very long compile times
that make it seems like Blender has stopped working.
This can be brought back in the future behind an option that users can
explicitly enabled.
Fix T100102
Ref D14923, D14763, T92212
Now all the same ones are available on CPU and GPU, which was previously not
possible due to lack of operator overloadng in OpenCL. Print functions are
no-ops on some GPUs.
Ref D15535
It should consistently use the Cycles pirmitive ID for self intersection detection,
not the one from the OptiX or Embree acceleration structure.
Differential Revision: https://developer.blender.org/D15632
Simplifies intersection code a little and slightly improves precision regarding
self intersection.
The parametric texture coordinate in shader nodes is still the same as before
for compatibility.
float8 is a reserved type in Metal, but is not implemented. So rename to
float8_t for now.
Also move back intersection handlers to kernel.metal, they can't be in the
class that encapsulates the other Metal kernel functions.
Having the OptiX/MetalRT/Embree/MetalRT implementations all in one file with
many #ifdefs became too confusing. Instead split it up per device, and also
move it together with device specific hit/filter/intersect functions and
associated data types.
All our intersections functions now work with unnormalized ray direction,
which means we no longer need to transform ray distance between world and
object space, they can all remain in world space.
There doesn't seem to be any real performance difference one way or the
other, but it does simplify the code.
For transparency, volume and light intersection rays, adjust these distances
rather than the ray start position. This way we increment the start distance
by the smallest possible float increment to avoid self intersections, and be
sure it works as the distance compared to be will be exactly the same as
before, due to the ray start position and direction remaining the same.
Fix T98764, T96537, hair ray tracing precision issues.
Differential Revision: https://developer.blender.org/D15455
The Metal backend now compiles and caches a second set of kernels which are
optimized for scene contents, enabled for Apple Silicon.
The implementation supports doing this both for intersection and shading
kernels. However this is currently only enabled for intersection kernels that
are quick to compile, and already give a good speedup. Enabling this for
shading kernels would be faster still, however this also causes a long wait
times and would need a good user interface to control this.
M1 Max samples per minute (macOS 13.0):
PSO_GENERIC PSO_SPECIALIZED_INTERSECT PSO_SPECIALIZED_SHADE
barbershop_interior 83.4 89.5 93.7
bmw27 1486.1 1671.0 1825.8
classroom 175.2 196.8 206.3
fishy_cat 674.2 704.3 719.3
junkshop 205.4 212.0 257.7
koro 310.1 336.1 342.8
monster 376.7 418.6 424.1
pabellon 273.5 325.4 339.8
sponza 830.6 929.6 1142.4
victor 86.7 96.4 96.3
wdas_cloud 111.8 112.7 183.1
Code contributed by Jason Fielder, Morteza Mostajabodaveh and Michael Jones
Differential Revision: https://developer.blender.org/D14645
* Rename "texture" to "data array". This has not used textures for a long time,
there are just global memory arrays now. (On old CUDA GPUs there was a cache
for textures but not global memory, so we used to put all data in textures.)
* For CUDA and HIP, put globals in KernelParams struct like other devices.
* Drop __ prefix for data array names, no possibility for naming conflict now that
these are in a struct.
