Cycles: Metal host-side code

This patch adds the Metal host-side code:

- Add all core host-side Metal backend files (device_impl, queue, etc)
- Add MetalRT BVH setup files
- Integrate with Cycles device enumeration code
- Revive `path_source_replace_includes` in util/path (required for MSL compilation)

This patch also includes a couple of small kernel-side fixes:

- Add an implementation of `lgammaf` for Metal [Nemes, Gergő (2010), "New asymptotic expansion for the Gamma function", Archiv der Mathematik](https://users.renyi.hu/~gergonemes/)
- include "work_stealing.h" inside the Metal context class because it accesses state now

Ref T92212

Reviewed By: brecht

Maniphest Tasks: T92212

Differential Revision: https://developer.blender.org/D13423

1 files changed, 3 insertions, 0 deletions

diff --git a/intern/cycles/device/multi/device.cpp b/intern/cycles/device/multi/device.cpp
index 2513df63489..baab84f4035 100644
--- a/intern/cycles/device/multi/device.cpp
+++ b/intern/cycles/device/multi/device.cpp
@@ -182,6 +182,9 @@ class MultiDevice : public Device {
         else if (bvh->params.bvh_layout == BVH_LAYOUT_MULTI_OPTIX_EMBREE)
           params.bvh_layout = sub.device->info.type == DEVICE_OPTIX ? BVH_LAYOUT_OPTIX :
                                                                       BVH_LAYOUT_EMBREE;
+        else if (bvh->params.bvh_layout == BVH_LAYOUT_MULTI_METAL_EMBREE)
+          params.bvh_layout = sub.device->info.type == DEVICE_METAL ? BVH_LAYOUT_METAL :
+                                                                      BVH_LAYOUT_EMBREE;
 
         /* Skip building a bottom level acceleration structure for non-instanced geometry on Embree
          * (since they are put into the top level directly, see bvh_embree.cpp) */