projection fixed-precision option?

[Fil]

I'm not sure how we could name it, but it would be useful to add an optional quantization/line simplification step at the end of the projection stream pipeline. For instance, the test outputs could be drastically reduced in size. And any SSR map rendered with plot would download faster.

[mbostock]

There’s an ancient PR in d3-path for this, I believe.

[Fil]

Yes, d3/d3-path#12. It's for generic paths, and probably more complicated than we'd want here (we know that we are in screen coordinates and are the last transform in the stream pipeline).

[mbostock]

probably more complicated than we'd want here

How is it complicated? I feel like that’s a pretty good existing solution and it’s nice that it would also work for pre-projected and planar geometry. I guess you’re saying we could do it as a point transform and abuse the interface by passing stream.point strings instead of numbers? But I think it would be best to fix this generically in d3-path since other people have wanted this for a while.

[Fil]

I meant more complicated in the sense that it also has to process arcs. But I also prefer if we can land it.

[mbostock]

I have updated d3/d3-path#12 and it should be ready to go now. Once that’s released as D3 7.8, we can adopt that here and switch to d3.pathFixed instead of d3.path.