[comp.sys.amiga] writemask use by layer library

dale@amiga.UUCP (03/12/87)

> Leo says:
>        I also tried setting the RastPort's Mask value to 0.  I thought this
>would prevent any subsequent rendering into the window.  It was here I
>encountered what appears to be at first sight a bug in the graphics library.
>After rendering into the window, I set the Mask to 0.  Everything appeared
>to be fixed on the screen.  Then I moved my CLI window around.  Everything
>underneath it was erased.  "Hmmm," I thought.  "Could it be that, when
>returning backup bitmaps to the visible screen, it's wrongly observing the
>Mask value?"
>
Yup, I think unfortunately this bug was noted too late in development
of 1.2.  Since SOOOO many things depend on the layer/graphics
library, a fix to this will be a major deal. By major deal I mean
it could cause major problems so extensive QA will be required.
Maybe in 1.3, that will be one of the first things that get
fixed. This will gove developers long enough lead time to scream
and cry about breaking their programs when I try to fix somehting
in the kickstart. Can't beat that backwards compatibility.
If there isn't too much fuss, like the developer was going to
rev his program anyway, or it wasn't selling that well anyway,
or it only breaks it a little eentsy bit than it may stay.

Dale Luck
of Commodore-Amiga, Inc.