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, 33 insertions, 0 deletions

diff --git a/intern/cycles/bvh/metal.mm b/intern/cycles/bvh/metal.mm
new file mode 100644
index 00000000000..90a52012f12
--- /dev/null
+++ b/intern/cycles/bvh/metal.mm
@@ -0,0 +1,33 @@
+/*
+ * Copyright 2021 Blender Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifdef WITH_METAL
+
+#  include "device/metal/bvh.h"
+
+CCL_NAMESPACE_BEGIN
+
+BVH *bvh_metal_create(const BVHParams &params,
+                      const vector<Geometry *> &geometry,
+                      const vector<Object *> &objects,
+                      Device *device)
+{
+  return new BVHMetal(params, geometry, objects, device);
+}
+
+CCL_NAMESPACE_END
+
+#endif /* WITH_METAL */