A little googling shows "Sweet Home 3D", but it is as slow as a wet week, reportedly. "Google Sketchup" requires wine, and I just don't need two applications to learn. A simple drawing utility which will allow me to generate lines and boxes of keyboard-entered dimensions, drag them (or select and move a keyboard-entered offset) would really do the trick. Although being able to rotate lines would also be useful for the roof. Ah ... there's LibreCAD. Does anyone know if that's so fancy that the learning curve is too long to be worth it for single-use? (Seems to be more for mechanical drawings.) AHA, I've just opened LibreOffice Draw for the first time, and spent an hour to get it to draw a box. (It defaults to a line width of 0, so nothing appears. Then it defaults to goddam fill. Then ... ) BUT, is there a way to move a line to a keyboard-entered position? Mouse-fiddling to a precise point is such a time-wasting torture that it's just not worth pursuing, I find.¹ After a few apt-cache searches, I've stumbled across: sketch - 3D diagrams for TeX from scene description language sketch-doc - Extra documentation for the sketch 3D line drawing system That seems overkill, with likely excessive learning curve, but ought to place objects at defined positions, with defined dimensions. These are unknowns: ardesia - free digital sketchpad software tetradraw - ANSI drawing and viewing utility Erik ¹ Eagle (PCB CAD) does that. I'm almost tempted to use it - I could use different track widths for different envelopes.