Cycles: Hydra fixes for stageMetersPerUnit and OpenGL context on Windows

Add "stageMetersPerUnit" render setting for USD files that have that set to
something other than the default (e.g. exported by Blender).

And fix a crash when an application creates a Hydra render pass on a thread
that does not have an OpenGL context current.

intern/cycles/hydra/display_driver.cpp

@@ -19,44 +19,66 @@ HDCYCLES_NAMESPACE_OPEN_SCOPE
 HdCyclesDisplayDriver::HdCyclesDisplayDriver(HdCyclesSession *renderParam, Hgi *hgi)
     : _renderParam(renderParam), _hgi(hgi)
 {
-#ifdef _WIN32
-  hdc_ = GetDC(CreateWindowA("STATIC",
-                             "HdCycles",
-                             WS_OVERLAPPEDWINDOW | WS_CLIPSIBLINGS | WS_CLIPCHILDREN,
-                             0,
-                             0,
-                             64,
-                             64,
-                             NULL,
-                             NULL,
-                             GetModuleHandle(NULL),
-                             NULL));
-
-  int pixelFormat = GetPixelFormat(wglGetCurrentDC());
-  PIXELFORMATDESCRIPTOR pfd = {sizeof(pfd)};
-  DescribePixelFormat((HDC)hdc_, pixelFormat, sizeof(pfd), &pfd);
-  SetPixelFormat((HDC)hdc_, pixelFormat, &pfd);
-
-  TF_VERIFY(gl_context_ = wglCreateContext((HDC)hdc_));
-  TF_VERIFY(wglShareLists(wglGetCurrentContext(), (HGLRC)gl_context_));
-#endif
-
-  glewInit();
-
-  glGenBuffers(1, &gl_pbo_id_);
 }
 
 HdCyclesDisplayDriver::~HdCyclesDisplayDriver()
+{
+  deinit();
+}
+
+void HdCyclesDisplayDriver::init()
+{
+#ifdef _WIN32
+  if (!gl_context_) {
+    hdc_ = GetDC(CreateWindowA("STATIC",
+                               "HdCycles",
+                               WS_OVERLAPPEDWINDOW | WS_CLIPSIBLINGS | WS_CLIPCHILDREN,
+                               0,
+                               0,
+                               64,
+                               64,
+                               NULL,
+                               NULL,
+                               GetModuleHandle(NULL),
+                               NULL));
+
+    int pixelFormat = GetPixelFormat(wglGetCurrentDC());
+    PIXELFORMATDESCRIPTOR pfd = {sizeof(pfd)};
+    DescribePixelFormat((HDC)hdc_, pixelFormat, sizeof(pfd), &pfd);
+    SetPixelFormat((HDC)hdc_, pixelFormat, &pfd);
+
+    TF_VERIFY(gl_context_ = wglCreateContext((HDC)hdc_));
+    TF_VERIFY(wglShareLists(wglGetCurrentContext(), (HGLRC)gl_context_));
+  }
+  if (!gl_context_) {
+    return;
+  }
+#endif
+
+  if (!gl_pbo_id_) {
+    if (glewInit() != GLEW_OK) {
+      return;
+    }
+
+    glGenBuffers(1, &gl_pbo_id_);
+  }
+}
+
+void HdCyclesDisplayDriver::deinit()
 {
   if (texture_) {
     _hgi->DestroyTexture(&texture_);
   }
 
-  glDeleteBuffers(1, &gl_pbo_id_);
+  if (gl_pbo_id_) {
+    glDeleteBuffers(1, &gl_pbo_id_);
+  }
 
 #ifdef _WIN32
-  TF_VERIFY(wglDeleteContext((HGLRC)gl_context_));
-  DestroyWindow(WindowFromDC((HDC)hdc_));
+  if (gl_context_) {
+    TF_VERIFY(wglDeleteContext((HGLRC)gl_context_));
+    DestroyWindow(WindowFromDC((HDC)hdc_));
+  }
 #endif
 }
 
@@ -192,6 +214,8 @@ void HdCyclesDisplayDriver::draw(const Params &params)
     return;
   }
 
+  init();
+
   // Cycles 'DisplayDriver' only supports 'half4' format
   TF_VERIFY(renderBuffer->GetFormat() == HdFormatFloat16Vec4);
 

intern/cycles/hydra/display_driver.h

@@ -19,6 +19,9 @@ class HdCyclesDisplayDriver final : public CCL_NS::DisplayDriver {
   ~HdCyclesDisplayDriver();
 
  private:
+  void init();
+  void deinit();
+
   void next_tile_begin() override;
 
   bool update_begin(const Params &params, int texture_width, int texture_height) override;

intern/cycles/hydra/file_reader.cpp

@@ -18,6 +18,7 @@
 #include <pxr/imaging/hd/task.h>
 #include <pxr/usd/usd/stage.h>
 #include <pxr/usd/usdGeom/camera.h>
+#include <pxr/usd/usdGeom/metrics.h>
 #include <pxr/usdImaging/usdImaging/delegate.h>
 
 HDCYCLES_NAMESPACE_OPEN_SCOPE
@@ -69,6 +70,9 @@ void HdCyclesFileReader::read(Session *session, const char *filepath, const bool
 
   /* Create render delegate. */
   HdRenderSettingsMap settings_map;
+  settings_map.insert(std::make_pair(HdCyclesRenderSettingsTokens->stageMetersPerUnit,
+                                     VtValue(UsdGeomGetStageMetersPerUnit(stage))));
+
   HdCyclesDelegate render_delegate(settings_map, session, true);
 
   /* Create render index and scene delegate. */
@@ -110,7 +114,7 @@ void HdCyclesFileReader::read(Session *session, const char *filepath, const bool
         HdSprim *sprim = render_index->GetSprim(HdPrimTypeTokens->camera, prim.GetPath());
         if (sprim) {
           HdCyclesCamera *camera = dynamic_cast<HdCyclesCamera *>(sprim);
-          camera->ApplyCameraSettings(session->scene->camera);
+          camera->ApplyCameraSettings(render_delegate.GetRenderParam(), session->scene->camera);
           break;
         }
       }

intern/cycles/hydra/render_delegate.cpp

@@ -26,20 +26,13 @@
 
 HDCYCLES_NAMESPACE_OPEN_SCOPE
 
+TF_DEFINE_PUBLIC_TOKENS(HdCyclesRenderSettingsTokens, HD_CYCLES_RENDER_SETTINGS_TOKENS);
+
 // clang-format off
 TF_DEFINE_PRIVATE_TOKENS(_tokens,
     (cycles)
     (openvdbAsset)
 );
-
-TF_DEFINE_PRIVATE_TOKENS(HdCyclesRenderSettingsTokens,
-    (stageMetersPerUnit)
-    ((device, "cycles:device"))
-    ((threads, "cycles:threads"))
-    ((timeLimit, "cycles:time_limit"))
-    ((samples, "cycles:samples"))
-    ((sampleOffset, "cycles:sample_offset"))
-);
 // clang-format on
 
 namespace {
@@ -127,17 +120,14 @@ HdCyclesDelegate::HdCyclesDelegate(const HdRenderSettingsMap &settingsMap,
   _renderParam = session_ ? std::make_unique<HdCyclesSession>(session_, keep_nodes) :
                             std::make_unique<HdCyclesSession>(GetSessionParams(settingsMap));
 
-  // If the delegate owns the session, pull any remaining settings
-  if (!session_) {
-    for (const auto &setting : settingsMap) {
-      // Skip over the settings known to be used for initialization only
-      if (setting.first == HdCyclesRenderSettingsTokens->device ||
-          setting.first == HdCyclesRenderSettingsTokens->threads) {
-        continue;
-      }
-
-      SetRenderSetting(setting.first, setting.second);
+  for (const auto &setting : settingsMap) {
+    // Skip over the settings known to be used for initialization only
+    if (setting.first == HdCyclesRenderSettingsTokens->device ||
+        setting.first == HdCyclesRenderSettingsTokens->threads) {
+      continue;
     }
+
+    SetRenderSetting(setting.first, setting.second);
   }
 }
 
@@ -328,7 +318,7 @@ HdBprim *HdCyclesDelegate::CreateBprim(const TfToken &typeId, const SdfPath &bpr
   }
 #endif
 
-  TF_RUNTIME_ERROR("Unknown Bprim type %s", typeId.GetText());
+  TF_CODING_ERROR("Unknown Bprim type %s", typeId.GetText());
   return nullptr;
 }
 

intern/cycles/hydra/render_delegate.h

@@ -11,6 +11,18 @@
 
 HDCYCLES_NAMESPACE_OPEN_SCOPE
 
+// clang-format off
+#define HD_CYCLES_RENDER_SETTINGS_TOKENS \
+    (stageMetersPerUnit) \
+    ((device, "cycles:device")) \
+    ((threads, "cycles:threads")) \
+    ((timeLimit, "cycles:time_limit")) \
+    ((samples, "cycles:samples")) \
+    ((sampleOffset, "cycles:sample_offset"))
+// clang-format on
+
+TF_DECLARE_PUBLIC_TOKENS(HdCyclesRenderSettingsTokens, HD_CYCLES_RENDER_SETTINGS_TOKENS);
+
 class HdCyclesDelegate final : public PXR_NS::HdRenderDelegate {
  public:
   HdCyclesDelegate(const PXR_NS::HdRenderSettingsMap &settingsMap,