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From Bug #36:
There are a couple of issues with the selection of Altivec alpha-blitting
routines in CalculateAlphaBlit() in src/video/SDL_Blit_A.c.
1) There's no check for the presence of Altivec when checking if the
Blit32to565PixelAlphaAltivec() routine can be selected.
2) Altivec cannot be used in video memory, and there's no check if the
destination surface is a hardware surface. (Alpha-blitting to a hardware
surface with GPU support is a bad idea, but somebody's bound to do it anyway.)
Patch to fix these attached.
author | Ryan C. Gordon <icculus@icculus.org> |
---|---|
date | Sun, 08 Jan 2006 21:18:15 +0000 |
parents | 355632dca928 |
children |
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<HTML ><HEAD ><TITLE >SDL_CDStatus</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="CD-ROM" HREF="cdrom.html"><LINK REL="PREVIOUS" TITLE="SDL_CDOpen" HREF="sdlcdopen.html"><LINK REL="NEXT" TITLE="SDL_CDPlay" HREF="sdlcdplay.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="sdlcdopen.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdlcdplay.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SDLCDSTATUS" ></A >SDL_CDStatus</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN7308" ></A ><H2 >Name</H2 >SDL_CDStatus -- Returns the current status of the given drive.</DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN7311" ></A ><H2 >Synopsis</H2 ><DIV CLASS="FUNCSYNOPSIS" ><A NAME="AEN7312" ></A ><P ></P ><PRE CLASS="FUNCSYNOPSISINFO" >#include "SDL.h"</PRE ><P ><CODE ><CODE CLASS="FUNCDEF" >CDstatus <B CLASS="FSFUNC" >SDL_CDStatus</B ></CODE >(SDL_CD *cdrom);</CODE ></P ><PRE CLASS="FUNCSYNOPSISINFO" >/* Given a status, returns true if there's a disk in the drive */ #define CD_INDRIVE(status) ((int)status > 0)</PRE ><P ></P ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN7319" ></A ><H2 >Description</H2 ><P >This function returns the current status of the given drive. Status is described like so: <PRE CLASS="PROGRAMLISTING" >typedef enum { CD_TRAYEMPTY, CD_STOPPED, CD_PLAYING, CD_PAUSED, CD_ERROR = -1 } CDstatus;</PRE ></P ><P >If the drive has a CD in it, the table of contents of the CD and current play position of the CD will be stored in the SDL_CD structure.</P ><P >The macro <TT CLASS="LITERAL" >CD_INDRIVE</TT > is provided for convenience, and given a status returns true if there's a disk in the drive.</P ><DIV CLASS="NOTE" ><BLOCKQUOTE CLASS="NOTE" ><P ><B >Note: </B ><TT CLASS="FUNCTION" >SDL_CDStatus</TT > also updates the <A HREF="sdlcd.html" ><SPAN CLASS="STRUCTNAME" >SDL_CD</SPAN ></A > structure passed to it.</P ></BLOCKQUOTE ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN7331" ></A ><H2 >Example</H2 ><PRE CLASS="PROGRAMLISTING" >int playTrack(int track) { int playing = 0; if ( CD_INDRIVE(SDL_CDStatus(cdrom)) ) { /* clamp to the actual number of tracks on the CD */ if (track >= cdrom->numtracks) { track = cdrom->numtracks-1; } if ( SDL_CDPlayTracks(cdrom, track, 0, 1, 0) == 0 ) { playing = 1; } } return playing; }</PRE ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN7334" ></A ><H2 >See Also</H2 ><P ><A HREF="sdlcd.html" ><TT CLASS="FUNCTION" >SDL_CD</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="sdlcdopen.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="sdlcdplay.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_CDOpen</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="cdrom.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL_CDPlay</TD ></TR ></TABLE ></DIV ></BODY ></HTML >