Mercurial > sdl-ios-xcode

view README.WinCE @ 5053:b5b42be9333c

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
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 86d0d01290ea
children
line wrap: on
line source


Project files for embedded Visual C++ 3.0, 4.0 and 
Visual Studio 2005 can be found in VisualCE.zip

SDL supports GAPI and WinDib output for Windows CE.

GAPI driver supports:

- all possible WinCE devices (Pocket PC, Smartphones, HPC)
  with different orientations of video memory and resolutions.
- 4, 8 and 16 bpp devices
- special handling of 8bpp on 8bpp devices
- VGA mode, you can even switch between VGA and GAPI in runtime
  (between 240x320 and 480x640 for example). On VGA devices you can
  use either GAPI or VGA.
- Landscape mode and automatic rotation of buttons and stylus coordinates.
  To enable landscape mode make width of video screen bigger than height.
  For example: 
    SDL_SetVideoMode(320,240,16,SDL_FULLSCREEN)
- WM2005
- SDL_ListModes

NOTE:
There are several SDL features not available in the WinCE port of SDL.

- DirectX is not yet available
- Semaphores are not available
- Joystick support is not available
- CD-ROM control is not available

In addition, there are several features that run in "degraded" mode:

Preprocessor Symbol		Effect
===================		=================================

SDL_systimer.c:
USE_GETTICKCOUNT		Less accurate values for SDL time functions
USE_SETTIMER			Use only a single marginally accurate timer

SDL_syswm.c:
DISABLE_ICON_SUPPORT		Can't set the runtime window icon

SDL_sysmouse.c:
USE_STATIC_CURSOR		Only the arrow cursor is available

SDL_sysevents.c:
NO_GETKEYBOARDSTATE		Can't get modifier state on keyboard focus

SDL_dibevents.c:
NO_GETKEYBOARDSTATE		Very limited keycode translation

SDL_dibvideo.c:
NO_GETDIBITS			Can't distinguish between 15 bpp and 16 bpp
NO_CHANGEDISPLAYSETTINGS	No fullscreen support
NO_GAMMA_SUPPORT		Gamma correction not available