There are examples ... examples/webgl_lines_fat.html (for instance) which indicate that thick lines can work.... but they only work for a line geometry. I have a bunch of line segments https://d3x0r.github.io/STFRPhysics/3d/indexArmProper.html which are not lines... but just segments; can't the same thing be done for those?
I don't really want to add 150,000 objects to the scene, but rather 1 object with 150,000 point/color pairs is much more reasonable. (depending on options a LOT of segments can be shown).
There's no example for them but both LineSegments2 and LineSegmentsGeometry in the examples/jsm/lines folder should do what you want.
As @gkjohnson said, what you want is already supported.
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There's no example for them but both LineSegments2 and LineSegmentsGeometry in the
examples/jsm/linesfolder should do what you want.