I am trying to figure out how to set the text color of the HoverTool tooltips text to match the color of the glyph whose source it is currently displaying information from. I have been unable to find where in the documentation the property I can use with cb_obj to set that color in some CustomJS code, or how to tap into the Source information used by the HoverTool to generate the tooltips.
BTW, in the tool tip these two choices give identical results. It appears that the hex code for the color will be shown either way:
hover.tooltips = [ ("Color", "$color[swatch]:Color"), ("Color", "$color[hex, swatch]:Color") ]