Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!uupsi!sunic!fuug!tuura!risto
From: risto@tuura.UUCP (Risto Lankinen)
Newsgroups: comp.windows.ms.programmer
Subject: Re: Does a window know when it is being overwritten?
Message-ID: <1159@tuura.UUCP>
Date: 7 May 91 08:46:46 GMT
References: <59847@siemens.siemens.com>
Organization: Nokia Data Systems Oy
Lines: 26

jrv@demon.siemens.com (James R Vallino) writes:


>The basic problem is that before anyone overwrites part of my client display
>memory, I have to save the pixels which will be overwritten.  I don't have
>another copy of the pixel data.  It has been generated by a coprocessor ...

Hi!

Wouldn't one solution then be to simply have the other copy around?  Plotting
to a compatible bitmap might even be faster than directly to the client area,
because it uses system memory (instead of display adapter's, which is slower
in many cases althou' maybe not generally).  Also, the window invalidization
(sp?) could be done less frequently.

Then there's a window style, <something>_SAVEBITS, which could be used for
the window's own dialogs to make them automatically memorize whatever they
write over upon initially popping up.  I'm also under the impression, that
the Windows' standard menus have this style flag set.

Terveisin: Risto Lankinen
-- 
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