How to flip y with d3.geoIdentity()? about d3-geo

[mbostock]

Added identity.reflectY in d3-geo 1.4 to make this easier and more obvious.

shp2json nad83.shp \
  | geoproject 'd3.geoIdentity().reflectY(true).fitSize([960, 500], d)' \
  | geo2svg \
  > test.svg

[mbostock]

You can’t use d3.geoIdentity for this. You need to use the more general d3.geoTransform. From the README:

var flipY = d3.geoTransform({
  point: function(x, y) {
    this.stream.point(x, -y);
  }
});

Let me find or cook up an example…

[mbostock]

Yeah, here it is:

shp2json nad83.shp \
  | geoproject 'd3.geoTransform({point: function(x, y) { this.stream.point(x, -y); }})' \
  | geoproject 'd3.geoIdentity().fitSize([960, 500], d)' \
  | geo2svg \
  > test.svg

So you have to chain two geoprojects together. Let me think about whether it’s possible to compose these transitions (which was the goal of the new graphics pipeline, which I haven’t had time to work on…).

[jstcki]

Very nice, thanks!

[jstcki]

Works like a charm, thank you!