<div class="gmail_quote">On 18 March 2012 17:46, Chris Wilson <<a href="mailto:chris@chris-wilson.co.uk" target="_blank">chris@chris-wilson.co.uk</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <div>On Sun, 18 Mar 2012 17:37:06 +0200, Christos Sotiriou <<a href="mailto:csotiriou@gmail.com" target="_blank">csotiriou@gmail.com</a>> wrote: > My problem is that drawing is too, too slow when drawing >100K rectangles. > I have tried double buffering in two ways (a) by using a cairo image > surface, drawing upon it and then copying the pattern to my drawing > context, and (b) by using cairo's surface_create_similar() function, which > supposedly uses X. > > I have found that drawing is simply toooooo slow, every which way. </div>My first suspicion is that you may simply be expecting too much. The fastest hardware I have can only render 2M 10x10 rectangles per second. Having said that, there are likely many tricks we can show you to improve your drawing performance, mostly to make you aware of exactly what you are asking to be drawn and to then simplify those operations until they match hardware capabilities. </blockquote><div> Dear Chris, Dear Dov, thanks again for your replies. I have thought through my current approach carefully, and have concluded that its weakness lies in the fact that I am drawing > 100K objects "live", i.e. whenever the window is exposed or the user zooms in/out, I use cairo to draw the double buffer image, then I copy it over to the GtkLayout window. I believe it would be easier to create an cairo image surface at the maximum required resolution, and then simply scale/pan that appropriately. Thanks, Christos. </div></div> -- -------------------------------------------------------------------------- Christos P. Sotiriou email: <a href="mailto:csotiriou@gmail.com" target="_blank">csotiriou@gmail.com</a> Cell: <a href="tel:%2B30%20697%208984%20222" value="+306978984222" target="_blank">+30 697 8984 222</a>