Re: [matplotlib-devel] Overlap with bar

>>>>> "David" == David Huard <dav...@gm...> writes:

    David> Hi, When plotting a large amount of bars, like

    >>>> bar(arange(500), rand(500))

    David> the bars seem to overlap and it produces a weird effect.

    David> My feeling is that the culprit is the contour line around
    David> each rectangle, who probably don't scale properly in this
    David> limit. In fact, the problem is maybe not so much that the
    David> contour width doesn't scale, but that the contour is drawn
    David> outside the rectangle.

    David> I'd be glad to submit a patch, but I'd need some directions
    David> (where in the code is the contour drawn ?)

This is likely due to either antialising of the bar patch.Rectangle
objects (does it help to turn the antialiased property off?) or
subpixel rendering (does it help to comment out these lines in
src/_backend_agg.cpp in the draw_polygon function?)

    //snapto pixel centers
    x = (int)x + 0.5;
    y = (int)y + 0.5;

JDH