[futurebasic] Re: CALL SetCCursor in a VBL task

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From: "L. Frank Turovich" <turovich@...>
Date: Thu, 8 Jan 1998 21:45:42 -0500
On 1/7/98 19:48 charlied@... wrote:

>I put together a color cursor animation and tried to run it within a VBL
>task. Boy, did it cause problems! Corrupted heap! I come to find out that
>SetCCursor moves memory around in trying to accomodate the color depth of
>the screen and moving memory around during an interrupt is a very bad thing
>to do.
>All I did was to call SetCCursor from within a FN from within the VBL task
>and apparently this is not enough. Has anyone had success with this type of
>thing? It's not enough to just run a simple test and say "See, it works!"
>because the heap won't be in jeopardy unless you are doing something that
>uses it like allocating and deallocating regions, GWorlds, etc.

Charlie --

Don't know if this will help, but it just came across my desk from Apple 
just now. It might offer some clues as to your color cursor problem.


[6]  Technote 1020 Revised: Color Cursor Quirks

If you're building an application that uses color cursors, you may
encounter some quirks present in Color QuickDraw. This technote
provides solutions to a few of the most common cursor problems.


L. Frank Turovich                              turovich@...
Sentient Fruit                    http://home.earthlink.net/~turovich