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view docs/html/sdlfillrect.html @ 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 | 355632dca928 |
children |
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<HTML ><HEAD ><TITLE >SDL_FillRect</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="Video" HREF="video.html"><LINK REL="PREVIOUS" TITLE="SDL_BlitSurface" HREF="sdlblitsurface.html"><LINK REL="NEXT" TITLE="SDL_DisplayFormat" HREF="sdldisplayformat.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="sdlblitsurface.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdldisplayformat.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SDLFILLRECT" ></A >SDL_FillRect</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN2351" ></A ><H2 >Name</H2 >SDL_FillRect -- This function performs a fast fill of the given rectangle with some color</DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN2354" ></A ><H2 >Synopsis</H2 ><DIV CLASS="FUNCSYNOPSIS" ><A NAME="AEN2355" ></A ><P ></P ><PRE CLASS="FUNCSYNOPSISINFO" >#include "SDL.h"</PRE ><P ><CODE ><CODE CLASS="FUNCDEF" >int <B CLASS="FSFUNC" >SDL_FillRect</B ></CODE >(SDL_Surface *dst, SDL_Rect *dstrect, Uint32 color);</CODE ></P ><P ></P ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN2361" ></A ><H2 >Description</H2 ><P >This function performs a fast fill of the given rectangle with <TT CLASS="PARAMETER" ><I >color</I ></TT >. If <TT CLASS="PARAMETER" ><I >dstrect</I ></TT > is <TT CLASS="LITERAL" >NULL</TT >, the whole surface will be filled with <TT CLASS="PARAMETER" ><I >color</I ></TT >.</P ><P >The color should be a pixel of the format used by the surface, and can be generated by the <A HREF="sdlmaprgb.html" >SDL_MapRGB</A > or <A HREF="sdlmaprgba.html" >SDL_MapRGBA</A > functions. If the color value contains an alpha value then the destination is simply "filled" with that alpha information, no blending takes place.</P ><P >If there is a clip rectangle set on the destination (set via <A HREF="sdlsetcliprect.html" >SDL_SetClipRect</A >) then this function will clip based on the intersection of the clip rectangle and the <TT CLASS="PARAMETER" ><I >dstrect</I ></TT > rectangle and the dstrect rectangle will be modified to represent the area actually filled.</P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN2374" ></A ><H2 >Return Value</H2 ><P >This function returns <SPAN CLASS="RETURNVALUE" >0</SPAN > on success, or <SPAN CLASS="RETURNVALUE" >-1</SPAN > on error.</P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN2379" ></A ><H2 >See Also</H2 ><P ><A HREF="sdlmaprgb.html" ><TT CLASS="FUNCTION" >SDL_MapRGB</TT ></A >, <A HREF="sdlmaprgb.html" ><TT CLASS="FUNCTION" >SDL_MapRGBA</TT ></A >, <A HREF="sdlblitsurface.html" ><TT CLASS="FUNCTION" >SDL_BlitSurface</TT ></A >, <A HREF="sdlrect.html" ><SPAN CLASS="STRUCTNAME" >SDL_Rect</SPAN ></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="sdlblitsurface.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="sdldisplayformat.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_BlitSurface</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="video.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL_DisplayFormat</TD ></TR ></TABLE ></DIV ></BODY ></HTML >