Re: [Matplotlib-users] Arrows that shimmy

2008-01-10 Thread Norman Davis
On Jan 9, 2008 11:53 AM, John Hunter <[EMAIL PROTECTED]> wrote: > On Jan 9, 2008 9:11 AM, Michael Droettboom <[EMAIL PROTECTED]> wrote: > > > You could comment out these two lines: > > > > x = (int)x + 0.5; > > y = (int)y + 0.5; > > > > and see if that corrects your wiggliness problem, ju

Re: [Matplotlib-users] Arrows that shimmy

2008-01-09 Thread John Hunter
On Jan 9, 2008 9:11 AM, Michael Droettboom <[EMAIL PROTECTED]> wrote: > You could comment out these two lines: > > x = (int)x + 0.5; > y = (int)y + 0.5; > > and see if that corrects your wiggliness problem, just to confirm that > as the source. > > The bigger question is -- there was pro

Re: [Matplotlib-users] Arrows that shimmy

2008-01-09 Thread Michael Droettboom
Norman, There is code (in 0.91, going back before my time) that rounds the vertices of polygons (which arrows in effect are) to the center of pixels. You can see it here inside RendererAgg::draw_polygon() in _backend_agg.cpp: agg::path_storage path; for (size_t j=0; j On the transforms

[Matplotlib-users] Arrows that shimmy

2008-01-09 Thread Norman Davis
Hi all, I' ve been using matplotlib to create some animations and it seems that the endpoints for arrow polygon lines are being rounded off to the nearest pixel. At least thats my guess. When viewing an animation the arrow changes shape and distorts as it moves around. The code below shows it o