issues: fixes #2414
Makes it possible to specify selection_glyph=None to mean no policy (i.e. use regular glyph)
Default behaviors are unchanged.
allow auto for non/selection glyphs
E.g. makes this possible:
import numpy as np
from bokeh.plotting import figure, show, output_file
N = 4000
x = np.random.random(size=N) * 100
y = np.random.random(size=N) * 100
radii = np.random.random(size=N) * 1.5
colors = [
"#%02x%02x%02x" % (int(r), int(g), 150) for r, g in zip(50+2*x, 30+2*y)
p = figure(tools="box_select")
r = p.scatter(x, y, radius=radii,
r.nonselection_glyph = None
output_file("color_scatter.html", title="color_scatter.py example")
show(p) # open a browser
before, setting to None gave the "auto" non-selection glyph.
Ping @mattpap seems ok? Not super important but its irritated me for ages, this seem more consistent and correct.
This seems fairly un-controversial, so I will merge it. If there are any objections later it is easy enough to revert.