Voronoi Labels in d3v4

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Voronoi Labels in d3v4

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Last edited Jun 29, 2016

Created on Jun 29, 2016

This example uses a Voronoi tessellation to place labels in a scatterplot, showing how cell area and centroid direction determine which points get labeled and where. The code generates 200 random points, computes their Voronoi polygons with d3.voronoi, and filters for cells larger than 2000 square pixels. For each qualifying point, it compares the centroid to the point itself, choosing a label orientation among top, right, bottom, or left based on the angle. The visualization renders SVG paths for cell borders and centroid lines, with labels positioned via text anchors and offsets.

AI-generated description

This example demonstrates the use of a Voronoi tessellation as a simple heuristic for labeling scatterplots. The area of the Voronoi cell associated with each point in the scatterplot is used to determine which points are labeled: points with large cells likely have enough room to accommodate labels. Then, the vector between the point and the associated cell’s centroid (shown in orange) is used to choose between four label orientations: top, right, bottom and left.

forked from <a href='http://bl.ocks.org/mbostock/'>mbostock</a>'s block: <a href='http://bl.ocks.org/mbostock/6909318'>Voronoi Labels</a>

gpl-3.0 Licensed

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