Vertex Paint: projection options

This makes vertex paint match image painting more closely.

- Add falloff shape option sphere/circle
  where sphere uses a 3D radius around the cursor and
  circle uses a 2D radius (projected), like previous releases.
- Add normal angle option so you can control the falloff.
- Add Cull option, to paint onto faces pointing away.

Disabling normals, culling and using circle falloff
allows you to paint through the mesh.

1 files changed, 27 insertions, 6 deletions

diff --git a/source/blender/makesrna/intern/rna_sculpt_paint.c b/source/blender/makesrna/intern/rna_sculpt_paint.c
index 09da34d59d8..6c89767ad29 100644
--- a/source/blender/makesrna/intern/rna_sculpt_paint.c
+++ b/source/blender/makesrna/intern/rna_sculpt_paint.c
@@ -671,23 +671,44 @@ static void rna_def_vertex_paint(BlenderRNA *brna)
 	RNA_def_struct_path_func(srna, "rna_VertexPaint_path");
 	RNA_def_struct_ui_text(srna, "Vertex Paint", "Properties of vertex and weight paint mode");
 
-	/* vertex paint only */
-	prop = RNA_def_property(srna, "use_normal", PROP_BOOLEAN, PROP_NONE);
-	RNA_def_property_boolean_sdna(prop, NULL, "flag", VP_NORMALS);
-	RNA_def_property_ui_text(prop, "Normals", "Apply the vertex normal before painting");
+	static EnumPropertyItem prop_falloff_items[] = {
+		{VP_FALLOFF_SHAPE_SPHERE, "SPHERE", 0, "Sphere", "Spherical falloff from the brush"},
+		{VP_FALLOFF_SHAPE_TUBE, "TUBE", 0, "Circle", "Circular falloff from the brush along the view"},
+		{0, NULL, 0, NULL, NULL}
+	};
+
+	prop = RNA_def_property(srna, "falloff_shape", PROP_ENUM, PROP_NONE);
+	RNA_def_property_enum_sdna(prop, NULL, "falloff_shape");
+	RNA_def_property_enum_items(prop, prop_falloff_items);
+	RNA_def_property_ui_text(prop, "Falloff", "");
+	RNA_def_property_update(prop, NC_SCENE | ND_TOOLSETTINGS, NULL);
+
+	prop = RNA_def_property(srna, "use_backface_culling", PROP_BOOLEAN, PROP_NONE);
+	RNA_def_property_boolean_negative_sdna(prop, NULL, "flag", VP_FLAG_PROJECT_BACKFACE);
+	RNA_def_property_ui_text(prop, "Cull", "Ignore vertices pointing away from the view (faster)");
+	RNA_def_property_update(prop, NC_SCENE | ND_TOOLSETTINGS, NULL);
+
+	prop = RNA_def_property(srna, "use_normal_falloff", PROP_BOOLEAN, PROP_NONE);
+	RNA_def_property_boolean_negative_sdna(prop, NULL, "flag", VP_FLAG_PROJECT_FLAT);
+	RNA_def_property_ui_text(prop, "Normals", "Paint most on faces pointing towards the view");
 	RNA_def_property_update(prop, NC_SCENE | ND_TOOLSETTINGS, NULL);
 	
+
 	prop = RNA_def_property(srna, "use_spray", PROP_BOOLEAN, PROP_NONE);
-	RNA_def_property_boolean_sdna(prop, NULL, "flag", VP_SPRAY);
+	RNA_def_property_boolean_sdna(prop, NULL, "flag", VP_FLAG_SPRAY);
 	RNA_def_property_ui_text(prop, "Spray", "Keep applying paint effect while holding mouse");
 	RNA_def_property_update(prop, NC_SCENE | ND_TOOLSETTINGS, NULL);
 
 	/* weight paint only */
 	prop = RNA_def_property(srna, "use_group_restrict", PROP_BOOLEAN, PROP_NONE);
-	RNA_def_property_boolean_sdna(prop, NULL, "flag", VP_ONLYVGROUP);
+	RNA_def_property_boolean_sdna(prop, NULL, "flag", VP_FLAG_VGROUP_RESTRICT);
 	RNA_def_property_ui_text(prop, "Restrict", "Restrict painting to vertices in the group");
 	RNA_def_property_update(prop, NC_SCENE | ND_TOOLSETTINGS, NULL);
 
+	prop = RNA_def_property(srna, "normal_angle", PROP_INT, PROP_UNSIGNED);
+	RNA_def_property_range(prop, 0, 90);
+	RNA_def_property_ui_text(prop, "Angle", "Paint most on faces pointing towards the view according to this angle");
+
 	/* Mirroring */
 	prop = RNA_def_property(srna, "radial_symmetry", PROP_INT, PROP_XYZ);
 	RNA_def_property_int_sdna(prop, NULL, "radial_symm");