Mercurial > sdl-ios-xcode
view src/timer/macos/FastTimes.h @ 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 | 74212992fb08 |
children | d910939febfa |
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/* File "FastTimes.h" - Original code by Matt Slot <fprefect@ambrosiasw.com> */ /* Created 4/24/99 - This file is hereby placed in the public domain */ /* Updated 5/21/99 - Calibrate to VIA, add TBR support, renamed functions */ /* Updated 10/4/99 - Use AbsoluteToNanoseconds() in case Absolute = double */ /* Updated 2/15/00 - Check for native Time Manager, no need to calibrate */ /* Updated 3/21/00 - Fixed ns conversion, create 2 different scale factors */ /* Updated 5/03/00 - Added copyright and placed into PD. No code changes */ /* This file is Copyright (C) Matt Slot, 1999-2000. It is hereby placed into the public domain. The author makes no warranty as to fitness or stability */ #ifndef __FAST_TIMES_HEADER__ #define __FAST_TIMES_HEADER__ /* **** **** **** **** **** **** **** **** **** **** **** **** **** **** **** */ /* **** **** **** **** **** **** **** **** **** **** **** **** **** **** **** */ extern void FastInitialize(void); extern UInt64 FastMicroseconds(void); extern UInt64 FastMilliseconds(void); extern StringPtr FastMethod(void); /* **** **** **** **** **** **** **** **** **** **** **** **** **** **** **** */ /* **** **** **** **** **** **** **** **** **** **** **** **** **** **** **** */ #endif /* __FAST_TIMES_HEADER__ */