Files
DarkflameServer/dUgcServer/Render/UgcRaysEmbreeGpu.h
Aaron Kimbrell db63fd2919 feat(ugc): ray_backend=embree-gpu traces on Intel GPUs with Embree's SYCL (optional build)
The third ray backend, so every machine has a library for it: Embree on x86
CPUs (embree), HIPRT on AMD and NVIDIA GPUs (hiprt), Embree through SYCL on
Intel Arc and Xe GPUs (embree-gpu).

- CMake option DLU_EMBREE_SYCL (off). dUgcServer/EmbreeSycl is a project of
  its own built by a SYCL compiler (DLU_SYCL_CXX; icpx through ONEAPI_ROOT or
  the path, or the open source DPC++'s clang++ through DPCPP_ROOT) as an
  external project: Embree 4.4 with EMBREE_SYCL_SUPPORT, linked statically and
  bound inside (-Bsymbolic, only its C functions exported, so it never meets
  the servers' own Embree), and the GPU kernels (nearest hit skipping a ray's
  triangle, any hit), into libdlu_embree_sycl next to the servers
- UgcRaysEmbreeGpu loads it the first time embree-gpu is asked for; one GPU for
  the process (embree_gpu_device picks it), the workers take turns, the
  occlusion rays in batches as for hiprt
- without the build, the library or a supported Intel GPU it falls back to
  embree and says why (the UGC server's log at start, --make-model on stderr)
- the option names, the settings page, the dashboard's picker, /reprocessproperty

Verified here: the default build and ctest; the SYCL build with the open source
DPC++ 7.1.0 (compiles, links against oneAPI's libsycl.so.9, exports only its C
functions); on this machine (no Intel GPU) it loads, finds no GPU and falls
back to embree. Not verified: tracing on an Intel GPU (none here).

Check: on a machine with an Intel Arc or Xe GPU and oneAPI, configure with
-DDLU_EMBREE_SYCL=ON and run UgcServer --make-model x.lxfml out embree-gpu;
the UGC tests then compare it with Embree.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-09-29 12:29:08 -05:00

26 lines
855 B
C++

#pragma once
#include <memory>
#include <string>
#include "UgcRays.h"
/**
* UgcRays' embree-gpu backend (built with DLU_EMBREE_SYCL): Embree 4 on an Intel GPU (Arc, Xe) through SYCL, in
* libdlu_embree_sycl next to the servers (built by a SYCL compiler, dUgcServer/EmbreeSycl), loaded when first asked for.
* One GPU for the process; the threads take turns on it.
*/
namespace UgcRaysEmbreeGpu {
// Whether it can be used: loads the library and sets the GPU up the first time
bool Available();
// Why it can't (empty when it can, or before it was first asked)
std::string Problem();
// The mesh on the GPU; null when the GPU fails (the caller uses another backend)
std::unique_ptr<UgcRays::Scene> Make(const UgcModel::Mesh& mesh);
// Which of the GPUs Embree supports (0: the first); before it is first used
void SetDevice(int index);
}