HO UK model rail
There are many makes of track planning software, one called SCARM is open source and therefore freely available. Unfortunately for me it doesn’t work directly on a Mac, although I can use it under bootcamp on the Apple iMac and it works very well. I was lucky to be able to get an early version of a Apple iMac program called Rail Modeller, and I used this to prototype various designs to fit my 3 x 1 metre baseboard.
All versions also provides a 2D view as well as a nice rotatable 3D presentation of layouts. Usefully it also allows you to input a stock list of the track you already have and from that it produces a want list of additional track parts you might need to complete your new layout. A listing of parts can be produced, providing their part numbers, quantities and if you wish you can add their costs. The track plan can be printed, screen shots saved, as well as printing the layouts at various scales.
I’ve only touched upon a small number of its features, but can wholeheartedly recommend it to you. Get the new express version and give a test drive!