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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 | 355632dca928 |
children |
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<HTML ><HEAD ><TITLE >SDL_LoadWAV</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+ "><LINK REL="HOME" TITLE="SDL Library Documentation" HREF="index.html"><LINK REL="UP" TITLE="Audio" HREF="audio.html"><LINK REL="PREVIOUS" TITLE="SDL_GetAudioStatus" HREF="sdlgetaudiostatus.html"><LINK REL="NEXT" TITLE="SDL_FreeWAV" HREF="sdlfreewav.html"></HEAD ><BODY CLASS="REFENTRY" BGCOLOR="#FFF8DC" TEXT="#000000" LINK="#0000ee" VLINK="#551a8b" ALINK="#ff0000" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >SDL Library Documentation</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="sdlgetaudiostatus.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdlfreewav.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SDLLOADWAV" ></A >SDL_LoadWAV</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN6816" ></A ><H2 >Name</H2 >SDL_LoadWAV -- Load a WAVE file</DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN6819" ></A ><H2 >Synopsis</H2 ><DIV CLASS="FUNCSYNOPSIS" ><A NAME="AEN6820" ></A ><P ></P ><PRE CLASS="FUNCSYNOPSISINFO" >#include "SDL.h"</PRE ><P ><CODE ><CODE CLASS="FUNCDEF" >SDL_AudioSpec *<B CLASS="FSFUNC" >SDL_LoadWAV</B ></CODE >(const char *file, SDL_AudioSpec *spec, Uint8 **audio_buf, Uint32 *audio_len);</CODE ></P ><P ></P ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN6826" ></A ><H2 >Description</H2 ><P ><TT CLASS="FUNCTION" >SDL_LoadWAV</TT > This function loads a WAVE <TT CLASS="PARAMETER" ><I >file</I ></TT > into memory.</P ><P >If this function succeeds, it returns the given <A HREF="sdlaudiospec.html" ><TT CLASS="FUNCTION" >SDL_AudioSpec</TT ></A >, filled with the audio data format of the wave data, and sets <TT CLASS="PARAMETER" ><I >audio_buf</I ></TT > to a <TT CLASS="FUNCTION" >malloc</TT >'d buffer containing the audio data, and sets <TT CLASS="PARAMETER" ><I >audio_len</I ></TT > to the length of that audio buffer, in bytes. You need to free the audio buffer with <A HREF="sdlfreewav.html" ><TT CLASS="FUNCTION" >SDL_FreeWAV</TT ></A > when you are done with it.</P ><P >This function returns <TT CLASS="LITERAL" >NULL</TT > and sets the SDL error message if the wave file cannot be opened, uses an unknown data format, or is corrupt. Currently raw, MS-ADPCM and IMA-ADPCM WAVE files are supported.</P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN6841" ></A ><H2 >Example</H2 ><PRE CLASS="PROGRAMLISTING" >SDL_AudioSpec wav_spec; Uint32 wav_length; Uint8 *wav_buffer; /* Load the WAV */ if( SDL_LoadWAV("test.wav", &wav_spec, &wav_buffer, &wav_length) == NULL ){ fprintf(stderr, "Could not open test.wav: %s\n", SDL_GetError()); exit(-1); } . . . /* Do stuff with the WAV */ . . /* Free It */ SDL_FreeWAV(wav_buffer);</PRE ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN6844" ></A ><H2 >See Also</H2 ><P ><A HREF="sdlaudiospec.html" ><SPAN CLASS="STRUCTNAME" >SDL_AudioSpec</SPAN ></A >, <A HREF="sdlopenaudio.html" ><TT CLASS="FUNCTION" >SDL_OpenAudio</TT ></A >, <A HREF="sdlfreewav.html" ><TT CLASS="FUNCTION" >SDL_FreeWAV</TT ></A ></P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="sdlgetaudiostatus.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="sdlfreewav.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_GetAudioStatus</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="audio.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL_FreeWAV</TD ></TR ></TABLE ></DIV ></BODY ></HTML >