fix HDRI orientation + flip on loading hdri images

Author: jeffamstutz

devices/rtx/scene/light/HDRI.cpp

@@ -88,7 +88,7 @@ LightGPUData HDRI::gpuData() const
 {
   auto retval = Light::gpuData();
 
-  const vec3 forward = glm::normalize(-m_direction);
+  const vec3 forward = glm::normalize(m_direction);
   const vec3 right = glm::normalize(glm::cross(m_up, forward));
   const vec3 up = glm::normalize(glm::cross(forward, right));
 

tsd/src/tsd/authoring/importers/detail/HDRImage.cpp

@@ -33,6 +33,7 @@ bool HDRImage::import(std::string fileName)
     return false;
 
   if (extension == ".hdr") {
+    stbi_set_flip_vertically_on_load(1);
     int w, h, n;
     float *imgData = stbi_loadf(fileName.c_str(), &w, &h, &n, STBI_rgb);
     width = w;

tsd/src/tsd/authoring/procedural/generate_hdri_dome.cpp

@@ -11,7 +11,7 @@ void generate_hdri_dome(Context &ctx, LayerNodeRef location)
     location = ctx.defaultLayer()->root();
 
   auto arr = ctx.createArray(ANARI_FLOAT32_VEC3, 1, 2);
-  std::vector<float3> colors = {float3(0.8f, 0.8f, 0.8f), float3(0.1f)};
+  std::vector<float3> colors = {float3(0.1f), float3(0.8f, 0.8f, 0.8f)};
   arr->setData(colors.data());
 
   auto [inst, hdri] = ctx.insertNewChildObjectNode<tsd::Light>(