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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
>Time</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+
"><LINK
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HREF="sdlgetticks.html"><META
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CONTENT="time"><META
NAME="KEYWORD"
CONTENT="function"></HEAD
><BODY
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><DIV
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><A
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></A
>Chapter 13. Time</H1
><DIV
CLASS="TOC"
><DL
><DT
><B
>Table of Contents</B
></DT
><DT
><A
HREF="sdlgetticks.html"
>SDL_GetTicks</A
>&nbsp;--&nbsp;Get the number of milliseconds since the SDL library initialization.</DT
><DT
><A
HREF="sdldelay.html"
>SDL_Delay</A
>&nbsp;--&nbsp;Wait a specified number of milliseconds before returning.</DT
><DT
><A
HREF="sdladdtimer.html"
>SDL_AddTimer</A
>&nbsp;--&nbsp;Add a timer which will call a callback after the specified number of milliseconds has
elapsed.</DT
><DT
><A
HREF="sdlremovetimer.html"
>SDL_RemoveTimer</A
>&nbsp;--&nbsp;Remove a timer which was added with
<A
HREF="sdladdtimer.html"
>SDL_AddTimer</A
>.</DT
><DT
><A
HREF="sdlsettimer.html"
>SDL_SetTimer</A
>&nbsp;--&nbsp;Set a callback to run after the specified number of milliseconds has
elapsed.</DT
></DL
></DIV
><P
>SDL provides several cross-platform functions for dealing with time.
It provides a way to get the current time, a way to wait a little while,
and a simple timer mechanism.  These functions give you two ways of moving an
object every x milliseconds:

<P
></P
><UL
><LI
><P
>Use a timer callback function.  This may have the bad effect that it runs in a seperate thread or uses alarm signals, but it's easier to implement.</P
></LI
><LI
><P
>Or you can get the number of milliseconds passed, and move the object if, for example, 30 ms passed.</P
></LI
></UL
>&#13;</P
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