Contour layer for scatterplot

[keller-mark]

Fixes #1775

Background

TODO:

• Allow to filter points by sample set membership - use stratification hook
• Option to weight points by the selected gene
• Option to simultaneously visualize data from multiple sample sets (e.g. with diverging colormap)?
• Option to use per-cell type contour layers using the cell type colors
  • Need to compute the isoline thresholds ahead of time (prior to cell type stratification?)
• Option to use colormapRange cutoffs when calculating weights.
• Option for user to modify or specify the percentiles used for the contour thresholds Support a mean aggregation strategy d3/d3-contour#78

Resources

• https://seaborn.pydata.org/generated/seaborn.kdeplot.html#seaborn.kdeplot
• https://github.com/mwaskom/seaborn/blob/9bdfc7484c15894dd35d58d3f16475389dfe4fe5/seaborn/distributions.py#L1816
• https://scanpy.readthedocs.io/en/stable/generated/scanpy.tl.embedding_density.html
• https://deck.gl/docs/api-reference/aggregation-layers/contour-layer#render-options
• https://observablehq.com/@d3/density-contours
• https://d3js.org/d3-contour/density
• https://github.com/scPolyphony/polyphony-vis/blob/54f19a9617710a0da2d2379cc18adae6285623b0/src/view-types/comparison/QRComparisonScatterplot.js#L214

Change List

Checklist

• Ensure PR works with all demos on the dev.vitessce.io homepage
• Open (draft) PR's into vitessce-python and vitessce-r if this is a release PR
• Documentation added or updated

[github-actions]

Size Change: +77.3 kB (+1%)

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