Workbench: Change Studio lighting

This is in order to have more flexible ligthing presets in the future.
The diffuse lighting from hdris was nice but lacked the corresponding
specular information. This is an attempt to make it possible to customize
the lighting and have a cheap/easy/nice-looking pseudo-PBR workflow.

* Add cheap PBR to Workbench with fresnel and better roughness support.
  This improves the look of the metallic surfaces and is easier to control.
* Add ambient light to studio lights settings: just a constant color added
  to the shading.
* Add Smooth option to studio lights settings: This option fakes the
  effect of making the light bigger making the lighting smoother for this
  light. Smoother lights gets reflected like a background hdri.
* Change default light settings to include the smooth params.
* Remove specular highlights from flat shading. (could be added back but
  how do we make it good looking?)
* If specular lighting is disabled, use base color without using metallic.
* Include a lot of code simplification/cleanup/confusion fix.

1 files changed, 19 insertions, 0 deletions

diff --git a/source/blender/makesrna/intern/rna_userdef.c b/source/blender/makesrna/intern/rna_userdef.c
index 921d8a3b65d..3610a9b8514 100644
--- a/source/blender/makesrna/intern/rna_userdef.c
+++ b/source/blender/makesrna/intern/rna_userdef.c
@@ -3478,6 +3478,13 @@ static void rna_def_userdef_solidlight(BlenderRNA *brna)
 	RNA_def_property_ui_text(prop, "Enabled", "Enable this OpenGL light in solid draw mode");
 	RNA_def_property_update(prop, 0, "rna_UserDef_viewport_lights_update");
 
+	prop = RNA_def_property(srna, "smooth", PROP_FLOAT, PROP_FACTOR);
+	RNA_def_property_float_sdna(prop, NULL, "smooth");
+	RNA_def_property_float_default(prop, 0.5f);
+	RNA_def_property_range(prop, 0.0f, 1.0f);
+	RNA_def_property_ui_text(prop, "Smooth", "Smooth the lighting from this light");
+	RNA_def_property_update(prop, 0, "rna_UserDef_viewport_lights_update");
+
 	prop = RNA_def_property(srna, "direction", PROP_FLOAT, PROP_DIRECTION);
 	RNA_def_property_float_sdna(prop, NULL, "vec");
 	RNA_def_property_array(prop, 3);
@@ -3490,6 +3497,12 @@ static void rna_def_userdef_solidlight(BlenderRNA *brna)
 	RNA_def_property_array(prop, 3);
 	RNA_def_property_ui_text(prop, "Specular Color", "Color of the light's specular highlight");
 	RNA_def_property_update(prop, 0, "rna_UserDef_viewport_lights_update");
+
+	prop = RNA_def_property(srna, "diffuse_color", PROP_FLOAT, PROP_COLOR);
+	RNA_def_property_float_sdna(prop, NULL, "col");
+	RNA_def_property_array(prop, 3);
+	RNA_def_property_ui_text(prop, "Diffuse Color", "Color of the light's diffuse highlight");
+	RNA_def_property_update(prop, 0, "rna_UserDef_viewport_lights_update");
 }
 
 static void rna_def_userdef_walk_navigation(BlenderRNA *brna)
@@ -4278,6 +4291,12 @@ static void rna_def_userdef_system(BlenderRNA *brna)
 	RNA_def_property_struct_type(prop, "UserSolidLight");
 	RNA_def_property_ui_text(prop, "Solid Lights", "Lights user to display objects in solid draw mode");
 
+	prop = RNA_def_property(srna, "light_ambient", PROP_FLOAT, PROP_COLOR);
+	RNA_def_property_float_sdna(prop, NULL, "light_ambient");
+	RNA_def_property_array(prop, 3);
+	RNA_def_property_ui_text(prop, "Ambient Color", "Color of the ambient light that uniformly lit the scene");
+	RNA_def_property_update(prop, 0, "rna_UserDef_viewport_lights_update");
+
 	prop = RNA_def_property(srna, "use_weight_color_range", PROP_BOOLEAN, PROP_NONE);
 	RNA_def_property_boolean_sdna(prop, NULL, "flag", USER_CUSTOM_RANGE);
 	RNA_def_property_ui_text(prop, "Use Weight Color Range",