Mercurial > sdl-ios-xcode
view docs/html/sdlupdaterects.html @ 1897:c2a27da60b18
Solved the performance problems by introducing the concept of a single-buffered
display, which is a fast path used for the whole-surface SDL 1.2 API.
Solved the flicker problems by implementing a backbuffer in the GDI renderer.
Unfortunately, now using the GDI renderer with a backbuffer and HBITMAPs is
significantly slower than SDL's surface code. *sigh*
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Wed, 12 Jul 2006 06:39:26 +0000 |
parents | 355632dca928 |
children |
line wrap: on
line source
<HTML ><HEAD ><TITLE >SDL_UpdateRects</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_UpdateRect" HREF="sdlupdaterect.html"><LINK REL="NEXT" TITLE="SDL_Flip" HREF="sdlflip.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="sdlupdaterect.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdlflip.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SDLUPDATERECTS" ></A >SDL_UpdateRects</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN1392" ></A ><H2 >Name</H2 >SDL_UpdateRects -- Makes sure the given list of rectangles is updated on the given screen.</DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN1395" ></A ><H2 >Synopsis</H2 ><DIV CLASS="FUNCSYNOPSIS" ><A NAME="AEN1396" ></A ><P ></P ><PRE CLASS="FUNCSYNOPSISINFO" >#include "SDL.h"</PRE ><P ><CODE ><CODE CLASS="FUNCDEF" >void <B CLASS="FSFUNC" >SDL_UpdateRects</B ></CODE >(SDL_Surface *screen, int numrects, SDL_Rect *rects);</CODE ></P ><P ></P ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN1402" ></A ><H2 >Description</H2 ><P >Makes sure the given list of rectangles is updated on the given screen. The rectangles must all be confined within the screen boundaries (no clipping is done).</P ><P >This function should not be called while <TT CLASS="PARAMETER" ><I >screen</I ></TT > is <A HREF="sdllocksurface.html" >locked</A >.</P ><DIV CLASS="NOTE" ><BLOCKQUOTE CLASS="NOTE" ><P ><B >Note: </B >It is adviced to call this function only once per frame, since each call has some processing overhead. This is no restriction since you can pass any number of rectangles each time.</P ><P >The rectangles are not automatically merged or checked for overlap. In general, the programmer can use his knowledge about his particular rectangles to merge them in an efficient way, to avoid overdraw.</P ></BLOCKQUOTE ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN1411" ></A ><H2 >See Also</H2 ><P ><A HREF="sdlupdaterect.html" ><TT CLASS="FUNCTION" >SDL_UpdateRect</TT ></A >, <A HREF="sdlrect.html" ><SPAN CLASS="STRUCTNAME" >SDL_Rect</SPAN ></A >, <A HREF="sdlsurface.html" ><SPAN CLASS="STRUCTNAME" >SDL_Surface</SPAN ></A >, <A HREF="sdllocksurface.html" ><TT CLASS="FUNCTION" >SDL_LockSurface</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="sdlupdaterect.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="sdlflip.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_UpdateRect</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_Flip</TD ></TR ></TABLE ></DIV ></BODY ></HTML >