Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!bionet!apple!oliveb!amiga!cbmvax!jesup
From: jesup@cbmvax.UUCP (Randell Jesup)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Help with Multitasking and Multiple Windows
Keywords: To many windows cause my program to smoke
Message-ID: <7541@cbmvax.UUCP>
Date: 4 Aug 89 18:36:17 GMT
References: <15645@watdragon.waterloo.edu>
Reply-To: jesup@cbmvax.UUCP (Randell Jesup)
Distribution: comp
Organization: Commodore Technology, West Chester, PA
Lines: 26

In article <15645@watdragon.waterloo.edu> ffishman@lion.waterloo.edu (Flynn D. Fishman) writes:
>This program opens a screen and then spawns several tasks which in turn
>open windows on the new screen.  
>
>The major problem is that the more tasks (actually process) I have running
>the better chance I have of guruing (completely, no system message or 
>anything just a grey screen or fire workds)
>
>If I put forbids or permits in key locations I can reduce this problem
>(If I put a forbid at the start of each process the problem goes away).  I am
>currently hypothesing that some of the graphics routines I use have
>some kind of contention.  But this does not make sense to me since they
>all use the rastport and therefore the Layers library which should lock
>when necessary.  The routines that I am using are:
>    RectFill, SetRast, SetAPen, Text, Move, Draw, WritePixel.

	Many of those don't involve layers, just the rastport.  There is no
locking of rastports.  What you need to do is create multiple rastports refer-
ing to the same bitmap/layers.  I believe copying the entire rastport is kosher,
provided you also make new tmpras's if you have one (i.e. don't try to share
a tmpras.)  Then a SetAPen will only affect one process, not both/all.

-- 
Randell Jesup, Keeper of AmigaDos, Commodore Engineering.
{uunet|rutgers}!cbmvax!jesup, jesup@cbmvax.cbm.commodore.com  BIX: rjesup  
Common phrase heard at Amiga Devcon '89: "It's in there!"