Javadoc
Tests whether a triangular ring would be eroded completely by the given
buffer distance.
This is a precise test. It uses the fact that the inner buffer of a
triangle converges on the inCentre of the triangle (the point
equidistant from all sides). If the buffer distance is greater than the
distance of the inCentre from a side, the triangle will be eroded completely.
This test is important, since it removes a problematic case where
the buffer distance is slightly larger than the inCentre distance.
In this case the triangle buffer curve "inverts" with incorrect topology,
producing an incorrect hole in the buffer.