Some operators like curve presets, color sample and some more were using object's
mode to distinguish in which mode user is currently painting. Such approach fails
in cases when there's paint mode active in 3D viewport and Image Editor.
Changed logic here to use some context's state like active space which helps
distinguishing current paint mode more accurate.
Ported all areas which uses paint_get_active() to new paint_get_active_from_context().
There're still some calls to paint_get_active(), but that shouldn't be harmful due
to that places indeed have object's mode as priority when getting paint mode.
effect for a render engine using new shading nodes. In short:
* No longer uses images assigned to faces in the uv layer, rather the active
image texture node is what is edited/painted/drawn.
* Textured draw type now shows the active image texture node, with solid
lighting.
* Material draw mode shows GLSL shader of a simplified material node tree,
using solid lighting.
* Textures for modifiers, brushes, etc, are now available from a dropdown in
the texture tab in the properties editor. These do not use new shading nodes
yet.
http://wiki.blender.org/index.php/Dev:2.6/Source/Render/TextureWorkflow