Hi G! https://www.babylonjs-playground.com/#165IV6#1267
Lines like these… also have a master .color property… which you can easily set to a Color3-type value. In the above PG, I start green, then turn red after 5 secs, then turn white after another 5 secs.
StandardMaterial doesn’t work on these babies.
As a side-note, I’m not sure you can “pick” a line… but you can certainly highlightLayer and glowLayer them. Both of those… have colors of their own, too… so you can leave the lines white, but then when glowLayer or highlightLayer activates, it will “appear” to change the line color… to the glow/highlight color.
Lots of options, but… standardMaterial colors is not one. Sorry. Stay tuned for more comments, as I could have said something wrong, and I might need correcting. (common for me)