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Fixed bug #943 Ozkan Sezer 2010-02-06 12:31:06 PST Hi: Here are some small fixes for compiling SDL against mingw-w64. (see http://mingw-w64.sourceforge.net/ . Despite the name, it supports both win32 and win64.) Two patches, one for SDL-1.2 and one for SDL-1.3 attached. src/audio/windx5/directx.h and src/video/windx5/directx.h (both SDL-1.2 and SDL-1.3.) I get compilation errors about some union not having a member named u1 and alike, because of other system headers being included before this one and them already defining DUMMYUNIONNAME and stuff. This header probably assumes that those stuff are defined in windef.h, but mingw-w64 headers define them in _mingw.h. Easily fixed by moving NONAMELESSUNION definition to the top of the file. SDL_dx5yuv.c (SDL-1.2-only) also needs to include the header before SDL_video.h to avoid the same problem. src/thread/win32/SDL_systhread.c (both SDL-1.2 and SDL-1.3.) : The __GNUC__ case for pfnSDL_CurrentBeginThread is 32-bit centric because _beginthreadex returns uintptr_t, not unsigned long which is 32 bits in win64. Changing the return type to uintptr_t fixes it. Hope these are useful. Thanks.
author Sam Lantinga <slouken@libsdl.org>
date Wed, 10 Mar 2010 15:04:13 +0000
parents 355632dca928
children
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<HTML
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>SDL_LockSurface</TITLE
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><H1
><A
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>SDL_LockSurface</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN1919"
></A
><H2
>Name</H2
>SDL_LockSurface&nbsp;--&nbsp;Lock a surface for directly access.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN1922"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN1923"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_LockSurface</B
></CODE
>(SDL_Surface *surface);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1929"
></A
><H2
>Description</H2
><P
><TT
CLASS="FUNCTION"
>SDL_LockSurface</TT
> sets up a surface for directly 
accessing the pixels.  Between calls to <TT
CLASS="FUNCTION"
>SDL_LockSurface</TT
>
and <TT
CLASS="FUNCTION"
>SDL_UnlockSurface</TT
>, you can write to and read from 
<TT
CLASS="PARAMETER"
><I
>surface-&#62;<TT
CLASS="STRUCTFIELD"
><I
>pixels</I
></TT
></I
></TT
>, using the pixel format stored in
<TT
CLASS="PARAMETER"
><I
>surface-&#62;<TT
CLASS="STRUCTFIELD"
><I
>format</I
></TT
></I
></TT
>.  Once you are done accessing the
surface, you should use <TT
CLASS="FUNCTION"
>SDL_UnlockSurface</TT
> to release it.</P
><P
>Not all surfaces require locking.  
If <TT
CLASS="LITERAL"
>SDL_MUSTLOCK</TT
>(<TT
CLASS="PARAMETER"
><I
>surface</I
></TT
>)
evaluates to <SPAN
CLASS="RETURNVALUE"
>0</SPAN
>, then you can read and write to the 
surface at any time, and the pixel format of the surface will not change. </P
><P
>No operating system or library calls should be made between lock/unlock
pairs, as critical system locks may be held during this time.</P
><P
>It should be noted, that since SDL 1.1.8 surface locks are recursive. This means that you can lock a surface multiple times, but each lock must have a match unlock.
<PRE
CLASS="PROGRAMLISTING"
>    .
    .
    SDL_LockSurface( surface );
    .
    /* Surface is locked */
    /* Direct pixel access on surface here */
    .
    SDL_LockSurface( surface );
    .
    /* More direct pixel access on surface */
    .
    SDL_UnlockSurface( surface );
    /* Surface is still locked */
    /* Note: Is versions &#60; 1.1.8, the surface would have been */
    /* no longer locked at this stage                         */
    .
    SDL_UnlockSurface( surface );
    /* Surface is now unlocked */
    .
    .</PRE
></P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1947"
></A
><H2
>Return Value</H2
><P
><TT
CLASS="FUNCTION"
>SDL_LockSurface</TT
> returns <SPAN
CLASS="RETURNVALUE"
>0</SPAN
>, 
or <SPAN
CLASS="RETURNVALUE"
>-1</SPAN
> if the surface couldn't be locked.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1953"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlunlocksurface.html"
><TT
CLASS="FUNCTION"
>SDL_UnlockSurface</TT
></A
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