matplotlib/basemap — pull request #89 by jswhit (2012-11-25 17:55:12+00:00)
Title: fix for issue #88

previously, the contourf and contour methods masked all points outside the map projection region. This meant that if a grid cell was partly inside and partly outside the map projection region, nothing was drawn, leaving a gap along the edge of the map. This is particularly noticeable for very coarse resolution grids. This commit only masks those points more than one grid length beyond the edge of the map projection region.

This may have some unintended consequences, so it will need a fair bit of testing before being merged into master.