Strange drawing limits

Hi,

I published a couple of bugs related to limits painting on Forms:

    http://bugs.impara.de/view.php?id=5222

To summarize: Drawing on forms does not work for x-coordinates bigger
than 2047, things get clipped. There seems to be a similar limit for
Display, that is at 4094. I couldn't observe such a limit on
y-coordinates, except for FormCanvas>>initialize that sets quite a
small clipping rectangle but it can be changed easily.

Anybody knowing where this limit for x-coordinates is coming from? Is
it in the VM? Is it in the code somewhere?

The limit on x-coordinates seems to me very low and makes Squeak
basically useless if you want to use it on bigger screens (multi
screen setup) or if you want to produce big graphics.

Cheers,
Lukas

--
Lukas Renggli
http://www.lukas-renggli.ch

Am 15.10.2006 um 11:57 schrieb Lukas Renggli:

I produced larger forms. Like, a 9600x7200x32 bit form downscaled to  
a 4800x3600 antialiased image for printing:

http://croquetweak.blogspot.com/2005/03/print-quality-screenshots.html

This means both bitblt and warpblt handle this just fine, as does the  
JPEG writer.

The resulting image is linked to at the end of the article, but  
beware, your browser may or may not like to display an image of that  
size ;-)

- Bert -

Thanks Bert,

> This means both bitblt and warpblt handle this just fine, as does the
> JPEG writer.

this was interesting to know. I looked even deeper into the process of
Squeak drawing and found yet another suspicious place where a sort of
a clipping is setup (see the whole process documented on Mantis).

Patching two places hardcoding clipping limits fixes the issue I
reported. The patches work fine for me, but maybe an expert can look
at the side-effects ;-) I suggest that we included those patches as
soon as possible as it is really a show-stopper for the graphic
capabilities of Squeak.

Lukas

--
Lukas Renggli
http://www.lukas-renggli.ch