mbostock/d3 — pull request #1586 by jasondavies (2013-10-15 21:45:33+00:00)
Title: Minor optimisation for projection.precision(0).

When resampling is turned off, d3_geo_resample can return a special
transform that only performs projection of points to 2D, rather than
performing any additional computations such as conversion to 3D
coordinates for resampling.