TexturePaint: Force Workbench Texture Color Mode

When in texture paint mode and in solid mode the object that is being
texture painted will be rendered by the workbench engine with textures.
All other objects would render the same. For other cases the texture paint
draw engine will still draw the texture.

The texture mode draw engine now only drawn the masks. The opacity
sliders influences the texture mask.

This change has been implemented conserably. In the future we need to
look into making this better, like adding support that every object
can be colored differently. Currently when rendering in the workbench
we can have up to 3 different color types active (what the user selected,
the fallback in case no materials have been configured and this one,
forcing textures)

Reviewed By: fclem, brecht

Differential Revision: https://developer.blender.org/D5190

1 files changed, 4 insertions, 0 deletions

diff --git a/source/blender/makesdna/DNA_view3d_types.h b/source/blender/makesdna/DNA_view3d_types.h
index 31ffb3efebd..e7a4f9cbd4e 100644
--- a/source/blender/makesdna/DNA_view3d_types.h
+++ b/source/blender/makesdna/DNA_view3d_types.h
@@ -433,6 +433,10 @@ enum {
   V3D_SHADING_TEXTURE_COLOR = 3,
   V3D_SHADING_OBJECT_COLOR = 4,
   V3D_SHADING_VERTEX_COLOR = 5,
+
+  /* Is used to display the object using the error color. For example when in
+   * solid texture paint mode without any textures configured */
+  V3D_SHADING_ERROR_COLOR = 999,
 };
 
 /** #View3DShading.background_type */