Node colours in draw_svg()

[gtsambos]

It would be nice to have the facility to colour the nodes in draw_svg(), like you still can with draw(). I'm happy to be assigned to this, but can't tackle it immediately.

[jeromekelleher]

I think we consciously dropped this in favour of the more powerful CSS based approach @gtsambos, like in tshi example

It's not as easy to use, but it's infinitely more flexible.

Is this a fair summary @hyanwong?

[jeromekelleher]

Related: #579

[hyanwong]

Yes, that's right. It seemed better not to set specific attributes like colour by a proliferation of parameters, when you can easily CSS it. There's code showing how to do it as the first example here: https://tskit.dev/tutorials/viz.html#styling

Suggestions on how to make this easier are most welcome. Perhaps the example there is too complicated? All you really need is

ts.draw_svg(style=".node.p0 > .sym {fill: red} .node.p1 > .sym {fill: green} .node.p2 > .sym {fill: blue}")

[hyanwong]

Or if you are want to use matplotlib colours, for example:

import matplotlib.colors as mcolors
ts.draw_svg(style="".join([
    f".node.p{p.id}>.sym {{fill: {col}}"
    for col, p in zip(mcolors.TABLEAU_COLORS.values(), ts.populations())
])

[benjeffery]

Closing this as CSS is the preferred route. Re-open if anyone feels strongly!