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view docs/html/sdldisplayformat.html @ 1012:f14e3059e138
Date: Mon, 13 Dec 2004 21:28:18 -0500
From: Jonathan Atkins
Subject: [SDL] SDL_SaveBMP width bugfix
this fixes the pitch versus width difference that can happen
(especially for 8bit and 24bit (with the exact RGBAmasks) surfaces)
when you use SDL_SaveBMP. The problem was the pitch was used
instead of the width, which in some cases is much wider than the
screen area you really want to save...making for ugly crud on the
saved image borders.
This code has been tested with & without pitch overhangs...and
with the right masks for 24 bit surfaces.
I tested 8,15,16,24,32-0RGB,32-RGBA(with no SDL_SRCALPHA flag).
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Tue, 14 Dec 2004 06:20:49 +0000 |
parents | 355632dca928 |
children |
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<HTML ><HEAD ><TITLE >SDL_DisplayFormat</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_FillRect" HREF="sdlfillrect.html"><LINK REL="NEXT" TITLE="SDL_DisplayFormatAlpha" HREF="sdldisplayformatalpha.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="sdlfillrect.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdldisplayformatalpha.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SDLDISPLAYFORMAT" ></A >SDL_DisplayFormat</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN2394" ></A ><H2 >Name</H2 >SDL_DisplayFormat -- Convert a surface to the display format</DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN2397" ></A ><H2 >Synopsis</H2 ><DIV CLASS="FUNCSYNOPSIS" ><A NAME="AEN2398" ></A ><P ></P ><PRE CLASS="FUNCSYNOPSISINFO" >#include "SDL.h"</PRE ><P ><CODE ><CODE CLASS="FUNCDEF" >SDL_Surface *<B CLASS="FSFUNC" >SDL_DisplayFormat</B ></CODE >(SDL_Surface *surface);</CODE ></P ><P ></P ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN2404" ></A ><H2 >Description</H2 ><P >This function takes a surface and copies it to a new surface of the pixel format and colors of the video framebuffer, suitable for fast blitting onto the display surface. It calls <A HREF="sdlconvertsurface.html" >SDL_ConvertSurface</A ></P ><P >If you want to take advantage of hardware colorkey or alpha blit acceleration, you should set the colorkey and alpha value before calling this function.</P ><P >If you want an alpha channel, see <A HREF="sdldisplayformatalpha.html" >SDL_DisplayFormatAlpha</A >.</P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN2411" ></A ><H2 >Return Value</H2 ><P >If the conversion fails or runs out of memory, it returns <SPAN CLASS="RETURNVALUE" >NULL</SPAN ></P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN2415" ></A ><H2 >See Also</H2 ><P ><A HREF="sdlconvertsurface.html" ><TT CLASS="FUNCTION" >SDL_ConvertSurface</TT ></A >, <A HREF="sdldisplayformatalpha.html" ><TT CLASS="FUNCTION" >SDL_DisplayFormatAlpha</TT ></A > <A HREF="sdlsetalpha.html" ><TT CLASS="FUNCTION" >SDL_SetAlpha</TT ></A >, <A HREF="sdlsetcolorkey.html" ><TT CLASS="FUNCTION" >SDL_SetColorKey</TT ></A >, <A HREF="sdlsurface.html" ><SPAN CLASS="STRUCTNAME" >SDL_Surface</SPAN ></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="sdlfillrect.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="sdldisplayformatalpha.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_FillRect</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_DisplayFormatAlpha</TD ></TR ></TABLE ></DIV ></BODY ></HTML >