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pythonzoomingscalingbokehglyph

Bokeh glyph line_width scaling

So I'm currently trying to plot a categorical heatmap in bokeh. It uses rects of 95% size in bokeh, mimicking a grid. I want to highlight areas using rectangles (quads). Getting it to plot is not the problem: Heatmap example plot

However, when zooming in and out, the line widths become a problem:

Zoomed out

I've read something concerning 'screen' and 'data' dimensioning, but I can't find how to apply this on glyph borders.

Workaround solution

I think I could write my own function that adds 4 lines for each rectangle, since line glyphs are scalable if I'm to believe the docs. That doesn't seem very elegant.

Any ideas?

Solution

  • Data space units only apply to things like the overall width or height or radius of a glyph. Line widths (e.g. glyph outlines) are always and only in screen units (pixels).

    However, is there are reason to allow zooming out at all? It seems nonsensical in the presence of categorical axes. You can prevent zooming and panning of categorical axes by setting the bounds property of ranges.