Compute contour polygons using marching squares.

Mike Bostock

Volcano contours

density.contours(data)

Density contours with linear binning

Smooth Contours

GeoTIFF contours II

GeoTIFF Contours

Cloud Contours

Animated Contours

Density contours

Contours

D3 Documentation

d3-contour

Explore and explain patterns in quantitative data using D3, Vega, and Observable Plot

Observable

Visualization

Gallery

I'm confused why the transformation above is `i*q + (-q/2)`, but the transformation in this function is effectively `i*q + (-q)`.  My mental model is that there's a "sample" domain and then the "pixel" domain, so the transformation function should be the same in both situations.  I tried experimenting, and it looks like it's correct (as in if I use the same function in both places, things are offset: https://observablehq.com/@pcarleton/working-with-d3-contours)  Am I missing something?

Paul Carleton