hdEmbree: add support for building against Embree versions 3 or 4

This supports upgrading Embree to a major version 4 release, so it includes
handling for the change in file paths between "embree3" and "embree4" and also
accounts for a small change in API in version 4 where RTCIntersectContext was
removed.

Author: mattyjams

pxr/imaging/plugin/hdEmbree/CMakeLists.txt

@@ -11,6 +11,12 @@ if (NOT ${PXR_BUILD_GPU_SUPPORT})
     return()
 endif()
 
+if (EMBREE_VERSION VERSION_GREATER_EQUAL 4.0.0)
+    add_definitions(-DEMBREE_MAJOR_VERSION=4)
+else()
+    add_definitions(-DEMBREE_MAJOR_VERSION=3)
+endif()
+
 pxr_plugin(hdEmbree
    LIBRARIES
         plug

pxr/imaging/plugin/hdEmbree/context.h

@@ -31,7 +31,11 @@
 #include "pxr/base/gf/matrix4f.h"
 #include "pxr/base/vt/array.h"
 
-#include <embree3/rtcore.h>
+#if defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
+    #include <embree4/rtcore.h>
+#else
+    #include <embree3/rtcore.h>
+#endif // defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
 
 PXR_NAMESPACE_OPEN_SCOPE
 

pxr/imaging/plugin/hdEmbree/mesh.h

@@ -32,8 +32,13 @@
 
 #include "pxr/imaging/plugin/hdEmbree/meshSamplers.h"
 
-#include <embree3/rtcore.h>
-#include <embree3/rtcore_ray.h>
+#if defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
+    #include <embree4/rtcore.h>
+    #include <embree4/rtcore_ray.h>
+#else
+    #include <embree3/rtcore.h>
+    #include <embree3/rtcore_ray.h>
+#endif // defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
 
 PXR_NAMESPACE_OPEN_SCOPE
 

pxr/imaging/plugin/hdEmbree/meshSamplers.h

@@ -29,8 +29,13 @@
 #include "pxr/imaging/hd/meshUtil.h"
 #include "pxr/base/vt/types.h"
 
-#include <embree3/rtcore.h>
-#include <embree3/rtcore_geometry.h>
+#if defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
+    #include <embree4/rtcore.h>
+    #include <embree4/rtcore_geometry.h>
+#else
+    #include <embree3/rtcore.h>
+    #include <embree3/rtcore_geometry.h>
+#endif // defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
 
 #include <bitset>
 

pxr/imaging/plugin/hdEmbree/pch.h

@@ -151,9 +151,15 @@
 #include <boost/unordered_map.hpp>
 #include <boost/utility/enable_if.hpp>
 #include <boost/weak_ptr.hpp>
+#if defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
+#include <embree4/rtcore.h>
+#include <embree4/rtcore_geometry.h>
+#include <embree4/rtcore_ray.h>
+#else
 #include <embree3/rtcore.h>
 #include <embree3/rtcore_geometry.h>
 #include <embree3/rtcore_ray.h>
+#endif // defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
 #include <tbb/atomic.h>
 #include <tbb/blocked_range.h>
 #include <tbb/cache_aligned_allocator.h>

pxr/imaging/plugin/hdEmbree/renderDelegate.h

@@ -30,8 +30,13 @@
 #include "pxr/imaging/plugin/hdEmbree/renderer.h"
 #include "pxr/base/tf/staticTokens.h"
 
+#if defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
+    #include <embree4/rtcore.h>
+#else
+    #include <embree3/rtcore.h>
+#endif // defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
+
 #include <mutex>
-#include <embree3/rtcore.h>
 
 PXR_NAMESPACE_OPEN_SCOPE
 

pxr/imaging/plugin/hdEmbree/renderParam.h

@@ -28,7 +28,11 @@
 #include "pxr/imaging/hd/renderDelegate.h"
 #include "pxr/imaging/hd/renderThread.h"
 
-#include <embree3/rtcore.h>
+#if defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
+    #include <embree4/rtcore.h>
+#else
+    #include <embree3/rtcore.h>
+#endif // defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
 
 PXR_NAMESPACE_OPEN_SCOPE
 

pxr/imaging/plugin/hdEmbree/renderer.cpp

@@ -653,9 +653,13 @@ HdEmbreeRenderer::_TraceRay(unsigned int x, unsigned int y,
     rayHit.ray.flags = 0;
     _PopulateRayHit(&rayHit, origin, dir, 0.0f);
     {
+#if defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
+      rtcIntersect1(_scene, &rayHit);
+#else
       RTCIntersectContext context;
       rtcInitIntersectContext(&context);
       rtcIntersect1(_scene, &context, &rayHit);
+#endif // defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
       //
       // there is something odd about how this is used in Embree. Is it reversed
       // here and then when it it used in
@@ -995,9 +999,13 @@ HdEmbreeRenderer::_ComputeAmbientOcclusion(GfVec3f const& position,
         shadow.flags = 0;
         _PopulateRay(&shadow, position, shadowDir, 0.001f);
         {
+#if defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
+          rtcOccluded1(_scene, &shadow);
+#else
           RTCIntersectContext context;
           rtcInitIntersectContext(&context);
           rtcOccluded1(_scene,&context,&shadow);
+#endif // defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
         }
 
         // Record this AO ray's contribution to the occlusion factor: a

pxr/imaging/plugin/hdEmbree/renderer.h

@@ -32,8 +32,13 @@
 #include "pxr/base/gf/matrix4d.h"
 #include "pxr/base/gf/rect2i.h"
 
-#include <embree3/rtcore.h>
-#include <embree3/rtcore_ray.h>
+#if defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
+    #include <embree4/rtcore.h>
+    #include <embree4/rtcore_ray.h>
+#else
+    #include <embree3/rtcore.h>
+    #include <embree3/rtcore_ray.h>
+#endif // defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
 
 #include <random>
 #include <atomic>

pxr/imaging/plugin/hdEmbree/testenv/testHdEmbree.cpp

@@ -40,7 +40,12 @@
 
 #include "pxr/base/tf/errorMark.h"
 
-#include <embree3/rtcore.h>
+#if defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
+    #include <embree4/rtcore.h>
+#else
+    #include <embree3/rtcore.h>
+#endif // defined(EMBREE_MAJOR_VERSION) && EMBREE_MAJOR_VERSION >= 4
+
 #include <iostream>
 
 PXR_NAMESPACE_USING_DIRECTIVE