Double buffering

SDL Development
1

How can I find out if double buffering is available? I had thought that
hw_available would tell me this (i.e. double buffering would be
available if a hardware surface can be created) but clearly I was
wrong. Where can I find an explanation of these issues? Thanks.
Gib

2

Gib Bogle wrote:

How can I find out if double buffering is available?

If you mean hardware page-flipping, the only way is to ask for it and see
if you got it. You get double-buffering with software surfaces too;
the SDL_DOUBLEBUF is a misnomer

3

Gib Bogle wrote:

Thanks Mattias, that is what I meant. How much faster is hardware db than
software db?

double-buffering in software is a lot slower, and does usually not allow
the update to be synchronised to the display’s vertical refresh. This does
not mean it’s useless; far from it

And how can one determine the availability of hardware
page-flipping before buying a video card?

by knowing if your target platform supports it, and if you have enough memory
to do so

4

[ CC:ed to sdl-list. Please do NOT mail me questions privately that are
of general interest, or I’ll have to start charging for answering ]

Gib Bogle wrote:

That is my question, how do I find out if a particular video card supports it (in
either W2K or Linux)? I want to buy the right card.

any card should do as long as it works with the host platform. And that
you should ask the card or OS vendor, not the sdl-list