LinearColorMapper for line glyph possible?

Community Support
1

I was wondering if it is possible to use a color mapper like LinearColorMapper for a line glyph?
It would be cool to interpolate the color of the line itself between the datapoints according to a given color mapper.

But this is currently not possible, right?

2

This is not currently possible, and will never be possible. The Line Bokeh glyph maps to the underlying HTML canvas line primitive which can only draw a single color.[1] If you want multiple segments that are different colors, you should user multi_line.

  1. Besides that, there is an additional reason why it can’t work. The connected topology of a line is different from other glyphs. A column of N points only gets you N-1 line segments (between the points), as opposed to a scatter which gets you N scatter points. All the columns of a CDS must always be the same length (i.e. N in this case) which means there are too many colors, you would have to somehow colormap N-1 segments based on N values and that does not work out. ↩︎

3

Thank you very much for your thorough explanation!

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