Train Set

This is a toy train set: a board of 14 by 10 tiles to lay a railway on, locomotives and cars to put on it, and a power switch to make them go. It is in the spirit of the electronic train sets of the early home computers — MacInooga Choo-Choo, on the first Macintosh in 1985, was one — where the fun was half in building the layout and half in running trains round it without crashing them. There is no score and no goal. Build something, run it, and see what happens.

Building a layout

Draw is the quickest way to lay track: drag across the board and every tile you pass through gets the piece that joins where you came from to where you went next — a straight if you kept going, a curve if you turned. Drag back over the tile you just left and the stroke shortens again, so a wrong turn is undone by retracing it. Drawing across an existing line cuts a crossing into it, and drawing off a line at an angle turns that tile into a set of points, so a branch line is one stroke.

Piece lays one exact piece on a tile, for when you want a particular switch facing a particular way. There are fifteen: two straights, four curves, a crossing, and eight sets of points — every way a straight and a curve can share an end. Tap a tile that already holds the piece you have picked and it turns a quarter, so you can pick roughly and turn it into place. Piece also works from the keyboard: arrow keys move around the board and Enter lays the piece.

Signal puts a signal on a plain straight or curve, and Uncoupler puts an uncoupling ramp on a straight. Scenery plants trees, houses, a station, water and the like on bare ground, and laying track over scenery clears it. Erase clears a tile: a train standing on it goes first, then the signal and track, then the scenery. Track under a train cannot be changed — move the train, or erase it, first.

Running trains

Pick Cars, choose a steam or diesel locomotive or one of five kinds of car, and tap the track to put it down. Every train gets a row in the list below the board with its own throttle, a Reverse button and a Stop button. Press Run and everything with a locomotive in it and its throttle up pulls away. Trains have weight: one takes two and a half seconds to reach full speed, a little over a second to stop from it, and cars with no locomotive coast to a halt rather than stopping dead. Reverse brakes a moving train to a stand before it changes direction. A train that runs out of track stops at the end of it. Fullscreen scales the board up to fill the display, with Run, the tools and the trains beside it; Escape or the Exit button brings the page back.

In Drive, tap a set of points to throw them. The route that is set is drawn in full and the other is greyed out. Points cannot be thrown with a train standing on them, but a train running through them from the back — the two branches towards the point end — throws them itself, the way the sprung points on a toy railway do, rather than coming off. Tap a signal to change it: a train comes to a stand before a red signal and goes again on green.

Coupling, uncoupling and derailing

Two trains that meet end to end at a crawl couple into one. A crawl is a closing speed no faster than 30% throttle into standing cars; any faster and both trains come off the rails and stay there, tipped over, until you press Rerail. Meeting anywhere else — two trains arriving at a crossing together, or one running into the side of another at the points — derails both whatever the speed. A rerailed train is put back on the track standing, and is allowed to pull clear of whatever it was tangled with.

To leave cars behind, tap an uncoupler in Drive to arm it. The next coupling to pass over it comes apart: the front of the train carries on with the locomotive, and the cars behind roll to a stop. The ramp then disarms itself, so it splits one coupling and no more. A train standing with a coupling right over an armed ramp is split where it stands as soon as the layout is running, which is how to drop a cut of cars exactly where you want them.

The layouts it comes with

Five layouts are in the menu next to Run. Countryside is an oval with a line through the middle and two trains on it. Oval is the train set out of the box. Figure eight shares one crossing between two loops, which is safe with one train and a test of timing with two. Passing loop has a freight standing in a siding, waiting for the passenger train to be switched into it. Yard has three cars standing in a spur and an uncoupler, for practising the shunting the original train sets were made for.

Saving and sharing a layout

Whatever you build is saved in this browser as you go, so it is still there next time. Copy link puts the whole layout — track, points, signals, scenery and every train where it stands — into the address, so it can be sent to somebody exactly as it is. Nothing is uploaded: the layout travels in the part of the address after the #, which browsers never send to a server. Opening someone else's link leaves your own layout saved until you keep theirs or start changing it, and the page says so when you open one.