Re: canvas drawing speed

From: Jin S. Choi <>
Date: Wed, 1 Mar 95 16:24:40 -0500

Erick Gallesio writes:
> > Along the same vein, is there any way to move regions of the canvas
> > around quickly without individually translating every object?
> >
> You cannot move easily a region (i.e. a rectangle of the canvas to another
> place), but "tags" permits to move a set of object in one shot (and it is
> fast!).

This is useful to know, but I don't think it will be helpful for my
application. I want to be able to scroll horizontally through a
potentially large set of vertical lines. I'd think just using a large
canvas, drawing all the lines, and putting a scrollbar on it would be
out of the question since the canvas might suck up all the memory
(unless it's implemented efficiently?), so I was planning to redraw the
lines myself, but that might be too slow. I guess I'll just have to try

Oh, by the way, does anyone know if one can change the behavior of the
scrollbar so that you cannot push the thumb partly off the bottom?
Received on Wed Mar 01 1995 - 22:30:51 CET

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