without hurting quick texture painting - ED_view3d_draw_offscreen will now output buffer with transparent alpha, if sky needed it should be alpha-undered later. - ED_view3d_draw_offscreen_imbuf now accepts alpha mode as an argument which could be either R_ADDSKY or R_PREMULALPHA - OpenGL render and sequencer's opengl preview will now reflect scene's Alpha Mode - Quick Edit will use OpenGL with transparent alpha mode