Re: how efficient is the canvas

[John R Sheets <dusk ravendusk org>]

Erik Andersen wrote:
> 
> Hmm.  GnomeHack uses the gnome canvas to create its map out of
> _lots_ of little images (3360 images at a time to be exact).  These
> images are tiled onto the canvas, and then a window which displays
> a subset of the whole map is displayed.  On my computer (a 433Mhz
> Celeron) it takes less than a second to render all of these 3360
> images and display them in the canvas.

Ooh, yeah, that's what I'd like to be able to do.  I'm working on
an online RPG client, too.

> Gnomehack used to take a _really_ long time to render also.  Then
> we fixed our code.  Based on the fact that GnomeHack can display all
> these tiles in a gnome canvas in well under a second, I think that
> your code could also use some improvement if it takes 6 seconds for
> only 36 small images.  Please feel free to check out how GnomeHack
> does things.

Thanks for the pointer, Erik.  I looked over the code, and it
looks pretty much like what I'm doing, except that I don't call
gdk_imlib_render() or gnome_canvas_item_lower_to_bottom().  Could
you go over your optimizations briefly?  Did you change how you
created the canvas items, or how they're rendered?

John