SDL_Flip() Vs SDL_UpdateRects()
 

Hi,

I thought that with SDL double-buffering was only available with a HW surface, which is only available full-screen (right?).

I'm using a SW (presumably single-buffered since I haven't requested double-buffering) screen surface, and SDL_UpdateRects() does not seem to work like I expected.

With SDL_UpdateRects() the areas requested are updated, but not drawn unless the window receives a VIDEOEXPOSE event... Spooky. However SDL_Flip(screen) (which should just act like SDL_UpdateRect(screen, 0, 0, 0, 0)) updates and draws everything ok. This however is a bit more expensive than i'd like.

The only thing I can think of is that SDL_Flip() creates and handles its own VIDEOEXPOSE event, while SDL_UpdateRects() doesn't.

So should I send a VIDEOEXPOSE event after calling SDL_UpdateRects(), or am I going wrong somewhere?

I read somewhere (I don't remember exactly where) that:

- HW surface isn't necessarily faster then SW surface. (except for 3D I assume)

- SDL_UpdateRects() works on SW surface(?) (I'm not very sure about this one)