[Freeciv-Dev] Re: Render speed test with imlib/xrender/sdl/pixbuf/ftwl

[Per Inge Mathisen <per@xxxxxxxxxxx>]

On Tue, 22 Mar 2005, Raimar Falke wrote:
> > It looks like you forgot to change the SDL surface to the display format.
> > This would explain the poor SDL performance, most likely.
>
> Only the output is blitted to the display surface. Once and this is
> not included in the timing. Feel free to point out errors/improvements
> in the source code.

You must be careful to convert the surfaces to be blitted to be of the
same format. Use SDL_ConvertSurface(), SDL_DisplayFormat() or
SDL_DisplayFormatAlpha() for this. See eg
http://www.libsdl.org/cgi/docwiki.cgi/SDL_5fConvertSurface

If you do not, SDL will do the conversion on the fly, very very slowly,
for each blit.

  - Per