When playing back animations a playhead is updated in all the animation editors.
The drawing of the playhead is part of the drawing of the main region RGN_TYPE_WINDOW that redraws the whole region.
This change will draw the play head and window scrollers when updating the screen. This affects the Action editor, Timeline, Graph editor, NLA editor and Sequence editor. There is noticeable speedup when using complex animation files.
Spring 02_020_A.anim.blend fps went from 11.8 to 12.5 when showing a timeline and a action editor on a Ryzen 1700.
This patch relates to D8073 as drawing channel region adds a RGN_DRAW_NO_REBUILD to the RGN_TYPE_WINDOW.
- When playing back animation the markers don't jump up/down when near the frame. This could be added back.
TODO after commit
- The NLA editor is redrawn on frame change. But doesn't have to. The cause of this isn't animation playback. it could have been the channel region. Need to retest.
- Rename region->do_draw_overlay to region->do_draw_paint_cursor to remove naming conflict with draw_overlay