Mercurial > sdl-ios-xcode
view README.WinCE @ 689:5bb080d35049
Date: Tue, 19 Aug 2003 17:57:00 +0200
From: Stephane Marchesin
Subject: Re: [SDL] [patch] MMX alpha blit patches with MMX detection
I think everything is correct now. I've done as much testing as I could,
but some real-world testing wouldn't hurt, I think.
The patch is here : http://icps.u-strasbg.fr/~marchesin/sdl_mmxblit.patch
If you do byte-by-byte comparison of the output between C and MMX
functions, you'll notice that the results for 555 and 565 RGB alpha
blits aren't exactly the same. This is because MMX functions for 555 and
565 RGB have an higher accuracy. If you want the exact same behaviour
that's possible by masking the three lower alpha bits in the MMX
functions. Just ask !
I removed one MMX function because after I fixed it to match its C
equivalent, it revealed to be slower than the C version on a PIII
(although a bit faster on an Athlon XP).
I've also added MMX and PIII replacements for SDL_memcpy. Those provide
some speed up in testvidinfo -benchmark (at least for me, under linux &
X11).
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Fri, 22 Aug 2003 05:51:19 +0000 |
parents | a6fa62b1be09 |
children | 86d0d01290ea |
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Project files for embedded Visual C++ 4.0 can be found in VisualCE.zip 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