When plotting a large amount of bars, like
the bars seem to overlap and it produces a weird effect.
My feeling is that the culprit is the contour line around each rectangle, who probably don’t scale properly in this limit. In fact, the problem is maybe not so much that the contour width doesn’t scale, but that the contour is drawn outside the rectangle.
I’d be glad to submit a patch, but I’d need some directions (where in the code is the contour drawn ?)
Thanks for matplotlib !