#107 Viking eating a lot of GPU/CPU with many trackpoints?!

[rooots]

After switching to Ubuntu 14.04, I recognised that when opening a file containing tracks with a lot of trackpoints (2000..3000 for example), zooming in onto the track (<= 8 pixelfact) and trying to pan about the map, Viking will become very sluggish, responding to pan movement only after a couple of seconds of wait. If I still keep on trying to zoom in and pan, Viking will eventually stall and become a case for kill -9.

I am used to seeing pretty high CPU load by Xorg (up to 50%) in those cases, but seeing Viking unresponsive was new to me. Unlike my previous Ubuntu install, where I always used the proprietary Catalyst driver (fglrx) I had used the free Radeon driver with the new Ubuntu install. Out of curiosity, I switched to the Catalyst driver and - surprise: No lag at all, smooth panning and zooming, no issues.
I mean, the free Radeon driver is known to show lower performance than the nonfree one, but hey - with a AMD HD5870 this shouldn't be an issue with a 2D app?!

I'm using gnome-panel (aka gnome-flashback) and this behaviour can be observed with both Compiz 3D activated and also Metacity 2D.

Have you already observed this kind of behaviour? Maybe this isn't Viking's fault at all, but I'd like to understand why this happens.

Cheers,
r.