A while back I came across: https://github.com/jemmybutton/fiziko a Metapost library for simulating wood grain in a style suitable to b/w illustrations from old physics books --- what would be the modern 3D equivalent? If I understand things correctly, at this time, it would only show in the initial preview, but would be lost (unless 3MF was used?) when making the actual object (though I'm almost tempted to make a wood grain "molded" surface like to what was used for plastic objects back in the 60s...) Has anyone else considered or tried or written on this? I've been trying to search but not finding much. William --  Sphinx of black quartz, judge my vow. https://designinto3d.com/