view src/video/SDL_pixels_c.h @ 5053:b5b42be9333c

Fixed bug #1026 Vittorio Giovara 2010-07-16 19:09:28 PDT i was reading SDL_renderer_gles and i noticed that every time we there is some gl call the gl state is modified with a couple of glEnableClientState()/glDisableClientState. While this is completely fine for desktops systems, this is a major performace kill on mobile devices, right where opengles is implemented. Normal practice in this case is to update the glstate once, keep it always the same and disable/enable other states only in very special occasions. On the web there's plenty of documentation (on the top of my head http://developer.apple.com/iphone/library/documentation/3DDrawing/Conceptual/OpenGLES_ProgrammingGuide/Performance/Performance.html#//apple_ref/doc/uid/TP40008793-CH105-SW5 ) and i personally tried this. I modified my code and got a 10 fps boost, then modified SDL_render_gles and shifted from 40 fps to 50 fps alone -- considering that i started from ~30fps i got an 80% performance increase with this technique. I have attached a dif of my changes, hope that it will be included in mainstream.
author Sam Lantinga <slouken@libsdl.org>
date Wed, 19 Jan 2011 23:56:16 -0800
parents f7b03b6838cb
children fb424691cfc7
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2010 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

/* Useful functions and variables from SDL_pixel.c */

#include "SDL_blit.h"

/* Pixel format functions */
extern SDL_PixelFormat *SDL_AllocFormat(int bpp,
                                        Uint32 Rmask, Uint32 Gmask,
                                        Uint32 Bmask, Uint32 Amask);
extern SDL_PixelFormat *SDL_InitFormat(SDL_PixelFormat * format, int bpp,
                                       Uint32 Rmask, Uint32 Gmask,
                                       Uint32 Bmask, Uint32 Amask);
extern void SDL_FormatChanged(SDL_Surface * surface);
extern void SDL_FreeFormat(SDL_PixelFormat * format);

/* Blit mapping functions */
extern SDL_BlitMap *SDL_AllocBlitMap(void);
extern void SDL_InvalidateMap(SDL_BlitMap * map);
extern int SDL_MapSurface(SDL_Surface * src, SDL_Surface * dst);
extern void SDL_FreeBlitMap(SDL_BlitMap * map);

/* Miscellaneous functions */
extern int SDL_CalculatePitch(SDL_Surface * surface);
extern void SDL_DitherColors(SDL_Color * colors, int bpp);
extern Uint8 SDL_FindColor(SDL_Palette * pal, Uint8 r, Uint8 g, Uint8 b);
extern void SDL_ApplyGamma(Uint16 * gamma, SDL_Color * colors,
                           SDL_Color * output, int ncolors);
/* vi: set ts=4 sw=4 expandtab: */