Lots of thinking about sprites today, and how they fit in with Chipmunk. But then near the end of today, I realized I was trying to fit the sprite system closely around Chipmunk, which is not what I want to do. So I've split off my notes about Chipmunk sprites from my notes about the new sprites in general.
Chipmunk is really cool, but I definitely don't want to make the whole sprite system based around the physics engine. Plenty of games have no use for rigid body dynamics. So the new sprite system will be easily integratable with Chipmunk, but not dependent on it.
Well, that's not strictly true. I might take advantage of Chipmunk's BB (bounding box) class to replace Rect. I haven't decided yet. If I do, BB would become a valid collision shape for sprites, equivalent to Rects now, but it would also support collision with polys, circles, and lines. If I go that route, BB will need some more functions added to it to make it even close to as versatile as Rect.
So, plenty to think about. The thinking continues tomorrow!