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The MacOSX Carbon/Cocoa/X11 all in one library patch. Relevant emails: To: SDL Developers <sdl@libsdl.org> From: =?ISO-8859-1?Q?Anders_F_Bj=F6rklund?= <afb@algonet.se> Date: Mon, 30 May 2005 23:29:04 +0200 Subject: [SDL] Mac OS X Video Drivers [patch] I've updated/added the Carbon and X11 video drivers to the Mac OS X port of SDL 1.2 (the CVS version), and made the Cocoa driver and runtime *optional*. The default is still Cocoa, and the "Quartz" driver. But you can now also use "toolbox" for Carbon, and "x11" for running with Apple's (or other) X11 server: export SDL_VIDEODRIVER=x11 export SDL_VIDEO_GL_DRIVER=/usr/X11R6/lib/libGL.dylib It also checks if the frameworks are available, by a: #include <Carbon/Carbon.h> or #import <Cocoa/Cocoa.h> (this should make it configure on plain Darwin as well?) Here are the new configure targets: --enable-video-cocoa use Cocoa/Quartz video driver default=yes --enable-video-carbon use Carbon/QuickDraw video driver default=yes --enable-video-x11 use X11 video driver default=no ./configure --enable-video-cocoa --enable-video-carbon --enable-video-x11 \ --x-includes=/usr/X11R6/include --x-libraries=/usr/X11R6/lib The Carbon version is just an updated version of the old SDL driver for Mac OS 9, and could probably be improved... (but it does work, including the Carbon version of SDLmain) If you disable cocoa, you can run with -framework Carbon only, and the C version of SDL_main.c. And if you disable carbon too, you can still use the X11 version which doesn't require SDLmain. I updated the DrawSprocket version, but did not include it. (no blitters or VRAM GWorlds etc. available on OS X anyway) Besides for Mac OS 9, I don't think there's any use for it ? And note that any performance on Mac OS X equals OpenGL anyway... You can get "fair" software SDL results on captured CG displays, but for decent frame rates you need to be using GL for rendering. Finally, here is the patch itself: http://www.algonet.se/~afb/SDL-12CVS-macvideo.patch --anders PS. It says "video", but as usual it applies to mouse/keyboard too. ------ To: A list for developers using the SDL library <sdl@libsdl.org> From: =?ISO-8859-1?Q?Anders_F_Bj=F6rklund?= <afb@algonet.se> Date: Sun, 4 Sep 2005 10:02:15 +0200 Subject: [SDL] Updated Mac patch Updated the previous Mac patch to disable Carbon by default. Also "fixed" the SDL.spec again, so that it builds on Darwin. http://www.algonet.se/~afb/SDL-1.2.9-mac.patch Also applied fine to SDL12 CVS, when I tried it.
author Ryan C. Gordon <icculus@icculus.org>
date Thu, 08 Sep 2005 06:16:14 +0000
parents 355632dca928
children
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<HTML
><HEAD
><TITLE
>SDL_SetAlpha</TITLE
><META
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><HR
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><H1
><A
NAME="SDLSETALPHA"
></A
>SDL_SetAlpha</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN2096"
></A
><H2
>Name</H2
>SDL_SetAlpha&nbsp;--&nbsp;Adjust the alpha properties of a surface</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN2099"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN2100"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_SetAlpha</B
></CODE
>(SDL_Surface *surface, Uint32 flag, Uint8 alpha);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2106"
></A
><H2
>Description</H2
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
>This function and the semantics of SDL alpha blending have changed since version 1.1.4. Up until version 1.1.5, an alpha value of 0 was considered opaque and a value of 255 was considered transparent. This has now been inverted: 0 (<TT
CLASS="LITERAL"
>SDL_ALPHA_TRANSPARENT</TT
>) is now considered transparent and 255 (<TT
CLASS="LITERAL"
>SDL_ALPHA_OPAQUE</TT
>) is now considered opaque.</P
></BLOCKQUOTE
></DIV
><P
><TT
CLASS="FUNCTION"
>SDL_SetAlpha</TT
> is used for setting the per-surface alpha
value and/or enabling and disabling alpha blending.</P
><P
>The<TT
CLASS="PARAMETER"
><I
>surface</I
></TT
> parameter specifies which surface whose alpha
attributes you wish to adjust. <TT
CLASS="PARAMETER"
><I
>flags</I
></TT
> is used to specify
whether alpha blending should be used (<TT
CLASS="LITERAL"
>SDL_SRCALPHA</TT
>) and
whether the surface should use RLE acceleration for blitting
(<TT
CLASS="LITERAL"
>SDL_RLEACCEL</TT
>). <TT
CLASS="PARAMETER"
><I
>flags</I
></TT
> can be an OR'd
combination of these two options, one of these options or 0. If
<TT
CLASS="LITERAL"
>SDL_SRCALPHA</TT
> is not passed as a flag then all alpha
information is ignored when blitting the surface. The
<TT
CLASS="PARAMETER"
><I
>alpha</I
></TT
> parameter is the per-surface alpha value; a
surface need not have an alpha channel to use per-surface alpha and blitting
can still be accelerated with <TT
CLASS="LITERAL"
>SDL_RLEACCEL</TT
>.</P
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
>The per-surface alpha value of 128 is considered a special case and
is optimised, so it's much faster than other per-surface values.</P
></BLOCKQUOTE
></DIV
><P
>Alpha effects surface blitting in the following ways:</P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN2126"
></A
><P
></P
><TABLE
BORDER="0"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>RGBA-&#62;RGB with <TT
CLASS="LITERAL"
>SDL_SRCALPHA</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><P
>The source is alpha-blended with the destination, using the alpha channel. <TT
CLASS="LITERAL"
>SDL_SRCCOLORKEY</TT
> and the per-surface alpha are ignored.</P
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>RGBA-&#62;RGB without <TT
CLASS="LITERAL"
>SDL_SRCALPHA</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><P
>The RGB data is copied from the source. The source alpha channel and the per-surface alpha value are ignored.</P
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>RGB-&#62;RGBA with <TT
CLASS="LITERAL"
>SDL_SRCALPHA</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><P
>The source is alpha-blended with the destination using the per-surface alpha
value. If <TT
CLASS="LITERAL"
>SDL_SRCCOLORKEY</TT
> is set, only the pixels not
matching the colorkey value are copied. The alpha channel of the copied pixels
is set to opaque.</P
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>RGB-&#62;RGBA without <TT
CLASS="LITERAL"
>SDL_SRCALPHA</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><P
>The RGB data is copied from the source and the alpha value of the copied pixels
is set to opaque. If <TT
CLASS="LITERAL"
>SDL_SRCCOLORKEY</TT
> is set, only the pixels
not matching the colorkey value are copied. </P
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>RGBA-&#62;RGBA with <TT
CLASS="LITERAL"
>SDL_SRCALPHA</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><P
>The source is alpha-blended with the destination using the source alpha
channel. The alpha channel in the destination surface is left untouched.
<TT
CLASS="LITERAL"
>SDL_SRCCOLORKEY</TT
> is ignored.</P
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>RGBA-&#62;RGBA without <TT
CLASS="LITERAL"
>SDL_SRCALPHA</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><P
>The RGBA data is copied to the destination surface. If <TT
CLASS="LITERAL"
>SDL_SRCCOLORKEY</TT
> is set, only the pixels not matching the colorkey value are copied.</P
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>RGB-&#62;RGB with <TT
CLASS="LITERAL"
>SDL_SRCALPHA</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><P
>The source is alpha-blended with the destination using the per-surface alpha value. If <TT
CLASS="LITERAL"
>SDL_SRCCOLORKEY</TT
> is set, only the pixels not matching the colorkey value are copied.</P
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
>RGB-&#62;RGB without <TT
CLASS="LITERAL"
>SDL_SRCALPHA</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><P
>The RGB data is copied from the source. If <TT
CLASS="LITERAL"
>SDL_SRCCOLORKEY</TT
> is set, only the pixels not matching the colorkey value are copied.</P
></TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
> Note that RGBA-&#62;RGBA blits (with SDL_SRCALPHA set) keep the alpha
of the destination surface. This means that you cannot compose two arbitrary
RGBA surfaces this way and get the result you would expect from "overlaying"
them; the destination alpha will work as a mask.</P
><P
>Also note that per-pixel and per-surface alpha cannot be combined;
the per-pixel alpha is always used if available</P
></BLOCKQUOTE
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2179"
></A
><H2
>Return Value</H2
><P
>This function returns <SPAN
CLASS="RETURNVALUE"
>0</SPAN
>, or
<SPAN
CLASS="RETURNVALUE"
>-1</SPAN
> if there was an error.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN2184"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlmaprgba.html"
><TT
CLASS="FUNCTION"
>SDL_MapRGBA</TT
></A
>,
<A
HREF="sdlgetrgba.html"
><TT
CLASS="FUNCTION"
>SDL_GetRGBA</TT
></A
>,
<A
HREF="sdldisplayformatalpha.html"
><TT
CLASS="FUNCTION"
>SDL_DisplayFormatAlpha</TT
></A
>,
<A
HREF="sdlblitsurface.html"
><TT
CLASS="FUNCTION"
>SDL_BlitSurface</TT
></A
></P
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