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Fixed bug #46
Date: Fri, 13 Jan 2006 18:09:45 -0500
From: mhall4400 vipmail kvcc edu
Subject: Possible SDL bug
Greetings
I believe Ive come across a bug in your SDL product (1.2.9), in the CD-ROM
control portion of the library.
When calling the SDL_CDPlay() function to play the last track of a CD using the
offset and length from an SDL_CD structure generated by SDL_CDOpen(), I get the
following error from a call to SDL_Error():
mciSendCommand() error: The specified parameter is out of range for the
specified command.
The code returning the error is:
SDL_CDPlay(g_playingDriveSDLCD,
g_playingDriveSDLCD->track[trackNumberInt].offset,
g_playingDriveSDLCD->track[trackNumberInt].length)
Subtracting one from the length of the provided length seems to repair the
problem:
SDL_CDPlay(g_playingDriveSDLCD,
g_playingDriveSDLCD->track[trackNumberInt].offset,
(g_playingDriveSDLCD->track[trackNumberInt].length) - 1)
Ive replicated this problem on Windows 98 SE (several months since last
patch), fully-patched Window ME, seldom-patched Windows XP SP1, and
fully-patched Windows XP SP2.
While investigating the issue, I came across a line in your librarys win32
source code in file \src\cdrom\win32\SDL_syscdrom.c (source code zip archive
from your download page), function: SDL_SYS_CDGetTOC(), line 226 where you add
1 to the value for length to fix MCI last track length bug. This may be the
source of the issue (because subtracting 1 from the length seems to resolve the
issue). Microsoft may have patched the referenced bug since you wrote that
line.
Mike Hall
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Tue, 14 Mar 2006 05:34:39 +0000 |
parents | 355632dca928 |
children |
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<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 -- 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->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 >