Mercurial > sdl-ios-xcode
view README.MacOS @ 1542:a8bf1aa21020
Fixed bug #15
SDL_blit_A.mmx-speed.patch.txt --
Speed improvements and a bugfix for the current GCC inline mmx
asm code:
- Changed some ops and removed some resulting useless ones.
- Added some instruction parallelism (some gain)
The resulting speed on my Xeon improved upto 35% depending on
the function (measured in fps).
- Fixed a bug where BlitRGBtoRGBSurfaceAlphaMMX() was
setting the alpha component on the destination surfaces (to
opaque-alpha) even when the surface had none.
SDL_blit_A.mmx-msvc.patch.txt --
MSVC mmx intrinsics version of the same GCC asm code.
MSVC compiler tries to parallelize the code and to avoid
register stalls, but does not always do a very good job.
Per-surface blending MSVC functions run quite a bit faster
than their pure-asm counterparts (upto 55% faster for 16bit
ones), but the per-pixel blending runs somewhat slower than asm.
- BlitRGBtoRGBSurfaceAlphaMMX and BlitRGBtoRGBPixelAlphaMMX (and all
variants) can now also handle formats other than (A)RGB8888. Formats
like RGBA8888 and some quite exotic ones are allowed -- like
RAGB8888, or actually anything having channels aligned on 8bit
boundary and full 8bit alpha (for per-pixel alpha blending).
The performance cost of this change is virtually 0 for per-surface
alpha blending (no extra ops inside the loop) and a single non-MMX
op inside the loop for per-pixel blending. In testing, the per-pixel
alpha blending takes a ~2% performance hit, but it still runs much
faster than the current code in CVS. If necessary, a separate function
with this functionality can be made.
This code requires Processor Pack for VC6.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Wed, 15 Mar 2006 15:39:29 +0000 |
parents | 37e3ca9254c7 |
children |
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============================================================================== Using the Simple DirectMedia Layer with MacOS 7,8,9 on PPC ============================================================================== These instructions are for people using the Apple MPW environment: http://developer.apple.com/tools/mpw-tools/ CodeWarrior projects are available in the CWprojects directory. ============================================================================== I. Building the Simple DirectMedia Layer libraries: (This step isn't necessary if you have the SDL binary distribution) First, unpack the MPWmake.sea.hqx archive and move SDL.make into the SDL directory. Start MPW Set the current directory within MPW to the SDL toplevel directory. Build "SDL" (Type Command-B and enter "SDL" in the dialog) If everything compiles successfully, you now have the PPC libraries "SDL" and "SDLmain.o" in the 'lib' subdirectory. ============================================================================== II. Building the Simple DirectMedia Layer test programs: First, unpack the MPWmake.sea.hqx archive, move the new rsrc directory to the main SDL directory, and move the makefiles in the new test subdirectory to the SDL 'test' subdirectory. Start MPW Set the current directory within MPW to the SDL 'test' subdirectory. Build the programs that have an associated MPW makefile (file ending with .make), including "testwin", "testalpha", and "graywin". Copy the SDL library file into the test directory, and run! ============================================================================== III. Building the Simple DirectMedia Layer demo programs: Copy one of the test program Makefiles to the demo directory and modify it to match the sources in the demo. ============================================================================== IV. Enjoy! :) If you have a project you'd like me to know about, or want to ask questions, go ahead and join the SDL developer's mailing list by sending e-mail to: sdl-request@libsdl.org and put "subscribe" into the subject of the message. Or alternatively you can use the web interface: http://www.libsdl.org/mailman/listinfo/sdl ==============================================================================