Cycles: add option to bake specular from active camera viewpoint

Previously it would bake viewed from above the surface. The new option can be
useful when the baked result is meant to be viewed from a fixed viewpoint or
with limited camera motion.

Some effort is made to give a continuous reflection on parts of the surface
invisible to the camera, but this is necessarily only a rough approximation.

Differential Revision: https://developer.blender.org/D15921

1 files changed, 19 insertions, 0 deletions

diff --git a/source/blender/makesrna/intern/rna_scene.c b/source/blender/makesrna/intern/rna_scene.c
index da30b7f2136..fdf8be9cb33 100644
--- a/source/blender/makesrna/intern/rna_scene.c
+++ b/source/blender/makesrna/intern/rna_scene.c
@@ -476,6 +476,20 @@ const EnumPropertyItem rna_enum_bake_save_mode_items[] = {
     {0, NULL, 0, NULL, NULL},
 };
 
+const EnumPropertyItem rna_enum_bake_view_from_items[] = {
+    {R_BAKE_VIEW_FROM_ABOVE_SURFACE,
+     "ABOVE_SURFACE",
+     0,
+     "Above Surface",
+     "Cast rays from above the surface"},
+    {R_BAKE_VIEW_FROM_ACTIVE_CAMERA,
+     "ACTIVE_CAMERA",
+     0,
+     "Active Camera",
+     "Use the active camera's position to cast rays"},
+    {0, NULL, 0, NULL, NULL},
+};
+
 #define R_IMF_VIEWS_ENUM_IND \
   {R_IMF_VIEWS_INDIVIDUAL, \
    "INDIVIDUAL", \
@@ -5413,6 +5427,11 @@ static void rna_def_bake_data(BlenderRNA *brna)
   RNA_def_property_ui_text(prop, "Save Mode", "Where to save baked image textures");
   RNA_def_property_update(prop, NC_SCENE | ND_RENDER_OPTIONS, NULL);
 
+  prop = RNA_def_property(srna, "view_from", PROP_ENUM, PROP_NONE);
+  RNA_def_property_enum_items(prop, rna_enum_bake_view_from_items);
+  RNA_def_property_ui_text(prop, "View From", "Source of reflection ray directions");
+  RNA_def_property_update(prop, NC_SCENE | ND_RENDER_OPTIONS, NULL);
+
   /* flags */
   prop = RNA_def_property(srna, "use_selected_to_active", PROP_BOOLEAN, PROP_NONE);
   RNA_def_property_boolean_sdna(prop, NULL, "flag", R_BAKE_TO_ACTIVE);