Mercurial > sdl-ios-xcode

view docs/html/sdlcreatergbsurface.html @ 892:dc29e5907694

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Date: Sun, 18 Apr 2004 16:09:53 -0400 (EDT) From: David MacCormack Subject: [SDL] Linux joystick patch I recently got myself a PS2 -> USB converter (a super joybox 5). It accepts 4 PSX/PS2 controllers. It's implemented as a HID, which is nice because it doesn't require its own driver, but the problem is that it's implemented as a *single* HID -- that is, it shows up as a single joystick with 19 axes, 4 hats, and 48 buttons. This poses a problem for a number of apps which use SDL (stella, fce ultra, zsnes, to name a few) and see only a single (physical) joystick even though there are really 4 (logical) joysticks. There are a number of these types of devices on the market, and I've seen others post messages (in the zsnes forum, for example) with the same problem, so I came up with what I think is a pretty generic solution. I patched src/joystick/linux/SDL_sysjoystic.c to include support for logical joysticks; basically, it's a static array and supporting functions that map a single physical joystick to multiple logical joysticks. The attached patch has the new code. It's wrapped inside #ifndef statements so that you can get the old behavior if you want.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 16 May 2004 18:46:24 +0000
parents 355632dca928
children
line wrap: on
line source

<HTML
><HEAD
><TITLE
>SDL_CreateRGBSurface</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_GetRGBA"
HREF="sdlgetrgba.html"><LINK
REL="NEXT"
TITLE="SDL_CreateRGBSurfaceFrom"
HREF="sdlcreatergbsurfacefrom.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="sdlgetrgba.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
></TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="sdlcreatergbsurfacefrom.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><H1
><A
NAME="SDLCREATERGBSURFACE"
></A
>SDL_CreateRGBSurface</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN1773"
></A
><H2
>Name</H2
>SDL_CreateRGBSurface&nbsp;--&nbsp;Create an empty SDL_Surface</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN1776"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN1777"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>SDL_Surface *<B
CLASS="FSFUNC"
>SDL_CreateRGBSurface</B
></CODE
>(Uint32 flags, int width, int height, int depth, Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1783"
></A
><H2
>Description</H2
><P
>Allocate an empty surface (must be called after <A
HREF="sdlsetvideomode.html"
>SDL_SetVideoMode</A
>)</P
><P
>If <TT
CLASS="PARAMETER"
><I
>depth</I
></TT
> is 8 bits an empty palette is allocated for the surface, otherwise a 'packed-pixel' <A
HREF="sdlpixelformat.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_PixelFormat</SPAN
></A
> is created using the <TT
CLASS="PARAMETER"
><I
>[RGBA]mask</I
></TT
>'s provided (see <A
HREF="sdlpixelformat.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_PixelFormat</SPAN
></A
>). The <TT
CLASS="PARAMETER"
><I
>flags</I
></TT
> specifies the type of surface that should be created, it is an OR'd combination of the following possible values.</P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN1795"
></A
><P
></P
><TABLE
BORDER="1"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_SWSURFACE</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>SDL will create the surface in system memory. This improves the performance of pixel level access, however you may not be able to take advantage of some types of hardware blitting.</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_HWSURFACE</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>SDL will attempt to create the surface in video memory. This will allow SDL to take advantage of Video-&#62;Video blits (which are often accelerated).</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_SRCCOLORKEY</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>This flag turns on colourkeying for blits from this surface. If
<TT
CLASS="LITERAL"
>SDL_HWSURFACE</TT
> is also specified and colourkeyed blits
are hardware-accelerated, then SDL will attempt to place the surface in
video memory.
Use <A
HREF="sdlsetcolorkey.html"
><TT
CLASS="FUNCTION"
>SDL_SetColorKey</TT
></A
>
to set or clear this flag after surface creation.</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="LITERAL"
>SDL_SRCALPHA</TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>This flag turns on alpha-blending for blits from this surface. If
<TT
CLASS="LITERAL"
>SDL_HWSURFACE</TT
> is also specified and alpha-blending blits
are hardware-accelerated, then the surface will be placed in video memory if
possible.
Use <A
HREF="sdlsetalpha.html"
><TT
CLASS="FUNCTION"
>SDL_SetAlpha</TT
></A
> to
set or clear this flag after surface creation.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
>If an alpha-channel is specified (that is, if <TT
CLASS="PARAMETER"
><I
>Amask</I
></TT
> is
nonzero), then the <TT
CLASS="LITERAL"
>SDL_SRCALPHA</TT
> flag is automatically
set. You may remove this flag by calling 
<A
HREF="sdlsetalpha.html"
><TT
CLASS="FUNCTION"
>SDL_SetAlpha</TT
></A
>
after surface creation.</P
></BLOCKQUOTE
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1826"
></A
><H2
>Return Value</H2
><P
>Returns the created surface, or <SPAN
CLASS="RETURNVALUE"
>NULL</SPAN
> upon error.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1830"
></A
><H2
>Example</H2
><PRE
CLASS="PROGRAMLISTING"
>    /* Create a 32-bit surface with the bytes of each pixel in R,G,B,A order,
       as expected by OpenGL for textures */
    SDL_Surface *surface;
    Uint32 rmask, gmask, bmask, amask;

    /* SDL interprets each pixel as a 32-bit number, so our masks must depend
       on the endianness (byte order) of the machine */
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
    rmask = 0xff000000;
    gmask = 0x00ff0000;
    bmask = 0x0000ff00;
    amask = 0x000000ff;
#else
    rmask = 0x000000ff;
    gmask = 0x0000ff00;
    bmask = 0x00ff0000;
    amask = 0xff000000;
#endif

    surface = SDL_CreateRGBSurface(SDL_SWSURFACE, width, height, 32,
                                   rmask, gmask, bmask, amask);
    if(surface == NULL) {
        fprintf(stderr, "CreateRGBSurface failed: %s\n", SDL_GetError());
        exit(1);
    }</PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1833"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlcreatergbsurfacefrom.html"
><TT
CLASS="FUNCTION"
>SDL_CreateRGBSurfaceFrom</TT
></A
>,
<A
HREF="sdlfreesurface.html"
><TT
CLASS="FUNCTION"
>SDL_FreeSurface</TT
></A
>,
<A
HREF="sdlsetvideomode.html"
><TT
CLASS="FUNCTION"
>SDL_SetVideoMode</TT
></A
>,
<A
HREF="sdllocksurface.html"
><TT
CLASS="FUNCTION"
>SDL_LockSurface</TT
></A
>,
<A
HREF="sdlpixelformat.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_PixelFormat</SPAN
></A
>,
<A
HREF="sdlsurface.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Surface</SPAN
></A
>
<A
HREF="sdlsetalpha.html"
><TT
CLASS="FUNCTION"
>SDL_SetAlpha</TT
></A
>
<A
HREF="sdlsetcolorkey.html"
><TT
CLASS="FUNCTION"
>SDL_SetColorKey</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="sdlgetrgba.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="sdlcreatergbsurfacefrom.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>SDL_GetRGBA</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_CreateRGBSurfaceFrom</TD
></TR
></TABLE
></DIV
></BODY
></HTML
>