source/blender/render/hydra/CMakeLists.txt

@@ -29,6 +29,7 @@ set(INC
   ../../blenlib
   ../../depsgraph
   ../../blenkernel
+  ../../imbuf
   ../../gpu
   ../../gpu/intern
   ../../python/intern

source/blender/render/hydra/scene_delegate/image.cc

@@ -8,6 +8,8 @@
 #include "BKE_image_save.h"
 #include "BLI_fileops.h"
 #include "BLI_path_util.h"
+#include "IMB_imbuf.h"
+#include "IMB_imbuf_types.h"
 
 #include "DNA_windowmanager_types.h"
 
@@ -16,18 +18,28 @@
 
 namespace blender::render::hydra {
 
+static std::string get_cache_file(const std::string &file_name, bool mkdir=true) {
+  char dir_path[FILE_MAX];
+  BLI_path_join(dir_path, sizeof(dir_path), BKE_tempdir_session(), "hydra_image_cache");
+  if (mkdir) {
+    BLI_dir_create_recursive(dir_path);
+  }
+
+  char file_path[FILE_MAX];
+  BLI_path_join(file_path, sizeof(file_path), dir_path, file_name.c_str());
+  return file_path;
+}
+
 static std::string cache_image_file(Image *image,
                                     BlenderSceneDelegate *scene_delegate,
                                     ImageUser *iuser,
                                     bool check_exist)
 {
-  char file_path[FILE_MAX];
   char file_name[32];
   snprintf(file_name, sizeof(file_name), "img_%016llx.hdr", (uintptr_t)image);
-  BLI_path_join(
-      file_path, sizeof(file_path), BKE_tempdir_session(), "hydra_image_cache", file_name);
 
-  if (check_exist && BLI_exists(file_path)) {
+  std::string file_path = get_cache_file(file_name);
+  if (check_exist && BLI_exists(file_path.c_str())) {
     return file_path;
   }
 
@@ -37,17 +49,18 @@ static std::string cache_image_file(Image *image,
 
   if (BKE_image_save_options_init(&opts, main, scene_delegate->scene, image, iuser, false, false))
   {
-    STRNCPY(opts.filepath, file_path);
+    STRNCPY(opts.filepath, file_path.c_str());
     if (BKE_image_save(nullptr, main, image, iuser, &opts)) {
-      CLOG_INFO(LOG_RENDER_HYDRA_SCENE, 1, "%s -> %s", image->id.name, file_path);
+      CLOG_INFO(LOG_RENDER_HYDRA_SCENE, 1, "%s -> %s", image->id.name, file_path.c_str());
     }
     else {
-      memset(file_path, 0, sizeof(file_path));
+      CLOG_ERROR(LOG_RENDER_HYDRA_SCENE, "Can't save %s", file_path.c_str());
+      file_path = "";
     }
   }
   BKE_image_save_options_free(&opts);
 
-  CLOG_INFO(LOG_RENDER_HYDRA_SCENE, 2, "%s -> %s", image->id.name, file_path);
+  CLOG_INFO(LOG_RENDER_HYDRA_SCENE, 2, "%s -> %s", image->id.name, file_path.c_str());
   return file_path;
 }
 
@@ -55,7 +68,7 @@ std::string cache_or_get_image_file(Image *image,
                                     BlenderSceneDelegate *scene_delegate,
                                     ImageUser *iuser)
 {
-  std::string file_path(FILE_MAX, 0);
+  std::string file_path;
   if (image->source == IMA_SRC_GENERATED) {
     file_path = cache_image_file(image, scene_delegate, iuser, false);
   }
@@ -64,6 +77,7 @@ std::string cache_or_get_image_file(Image *image,
   }
   else {
     Main *main = CTX_data_main(scene_delegate->context);
+    file_path.reserve(FILE_MAX);
     BKE_image_user_file_path_ex(main, iuser, image, file_path.data(), false, true);
 
     if (!pxr::HioImageRegistry::GetInstance().IsSupportedImageFile(file_path)) {
@@ -75,4 +89,24 @@ std::string cache_or_get_image_file(Image *image,
   return file_path;
 }
 
+std::string cache_image_color(float color[4], const std::string &name)
+{
+  std::string file_path = get_cache_file(name + ".hdr");
+
+  ImBuf *ibuf = IMB_allocImBuf(4, 4, 32, IB_rectfloat);
+  IMB_rectfill(ibuf, color);
+  ibuf->ftype = IMB_FTYPE_RADHDR;
+
+  if (IMB_saveiff(ibuf, file_path.c_str(), IB_rectfloat)) {
+    CLOG_INFO(LOG_RENDER_HYDRA_SCENE, 1, "%s", file_path.c_str());
+  }
+  else {
+    CLOG_ERROR(LOG_RENDER_HYDRA_SCENE, "Can't save %s", file_path.c_str());
+    file_path = "";
+  }
+  IMB_freeImBuf(ibuf);
+
+  return file_path;
+}
+
 }  // namespace blender::render::hydra

source/blender/render/hydra/scene_delegate/image.h

@@ -13,5 +13,6 @@ class BlenderSceneDelegate;
 std::string cache_or_get_image_file(Image *image,
                                     BlenderSceneDelegate *scene_delegate,
                                     ImageUser *iuser);
+std::string cache_image_color(float color[4], const std::string &name);
 
 }  // namespace blender::render::hydra

source/blender/render/hydra/scene_delegate/world.cc

@@ -100,6 +100,13 @@ void WorldData::init()
     data_[pxr::HdLightTokens->exposure] = world->exposure;
     data_[pxr::HdLightTokens->color] = pxr::GfVec3f(world->horr, world->horg, world->horb);
   }
+
+  if (data_.find(pxr::HdLightTokens->textureFile) == data_.end()) {
+    pxr::GfVec3f c = data_[pxr::HdLightTokens->color].Get<pxr::GfVec3f>();
+    float color[4] = {c[0], c[1], c[2], 1.0f};
+    std::string image_path = cache_image_color(color, "world");
+    data_[pxr::HdLightTokens->textureFile] = pxr::SdfAssetPath(image_path, image_path);
+  }
 }
 
 void WorldData::insert()