seaborn.objects: z order of layers

[stanmart]

Is there any way to determine the z order of the various layers on a plot with multiple objects? For example, Dots seems to be plotted earlier than Dashes, regardless of the order of the .add method calls. In certain cases, it would be nice to have control over which layer comes first, e.g. to make sure that elements representing summary statistics are easily visible.

[mwaskom]

seaborn.objects currently does not do anything different than matplotlib, which assigns different default zorders to different artist classes. I agree that it would make sense to have the zorder appear more responsive to the order that layers are added. For now, you can use the artist_kws argument of any Mark to assign the artists comprising the mark a specific zorder.

[stanmart]

Thank you, passing the artist_kws is indeed a great solution for the moment. If you ever decide to extend seaborn's API to handle this without going down to matplotlib, I am happy to (try to) help.

[matulad]

Hi @mwaskom ,

change proposal - let's add those two lines to the so.Plot().add() method (e.g. to rows 541 or so):

zorder = len(self._layers) + 1
mark.artist_kws["zorder"] = mark.artist_kws.get("zorder", zorder)

Simple example - let's say I would like to plot points over a line:

(
  so.Plot(tips.sample(20), "total_bill", "tip")
  .add(so.Line(linewidth=3))
  .add(so.Dot(pointsize=50, color="red"))
)

Without the two lines:

With the lines:

Happy to hear your feedback. Thanks.