Add mjr_sceneParams for creating Scene objects.

PiperOrigin-RevId: 907589621
Change-Id: If7537cf6fbac6d6418ac2bf8315714ada969511d

src/experimental/filament/render_context_filament.cc

@@ -63,6 +63,12 @@ void mjr_defaultMeshData(mjrMeshData* data) {
   std::memset(data, 0, sizeof(mjrMeshData));
 }
 
+void mjr_defaultSceneParams(mjrSceneParams* params) {
+  params->enable_post_processing = true;
+  params->enable_reflections = true;
+  params->enable_shadows = true;
+}
+
 void mjr_defaultLightParams(mjrLightParams* params) {
   params->type = mjLIGHT_POINT;
   params->texture = nullptr;