Controls

Geometry

The "A" key toggles the boundary texture from shape color to white. See Settings for the whole story.

Control-R reloads the current scene from the scene file. This is very handy if you've made a mess of things or if you're working on some changes to the file.

The "page up" and "page down" keys let you flip through all the scene files in the current directory in alphabetical order.

Control-N removes the front faces of the blocks so that you can see inside. It's like X-ray vision!

Control-S turns separation on and off. When it's off, you can move through the blocks and the ground, and the blocks can move through each other and through the ground. You can use this to untangle blocks that are packed together too tightly, and also to look at blocks from the inside (this requires control-N too).

Blocks

The space bar is used to select and deselect blocks. When a block is selected, the motion keys apply to the block instead of to you. See Block Motion for more about that.

If the selection marks are getting in the way, you can use control-H to hide them.

Control-W scatters the blocks all over the mat at random. I'm not sure what the best verb is: explode? scramble? knock down? In any case, the mnemonic is "wham!". Control-R (above) acts as an inverse operation. Note: when you're in align mode the blocks are scattered into aligned positions.

The "insert" key adds a new block of whatever type is currently selected at a random position on the mat. The "delete" key deletes the block that you're pointing at. Neither of these work when a block is selected. If you hit "shift-insert", you can change the selected block type and also request a large quantity all at once. Note: the performance of the graphics engine is a lot better than I expected, but please don't overdo it with the blocks. One or two hundred seems to be fine though!

The "P" key lets you paint the blocks. If you paint the wrong face, you can press "P" again to unpaint it. You can control the color and whether you're painting faces or whole blocks by pressing shift-P.

Trains

The keys X-C-V are the train speed control. "V" speeds the train up, "X" slows it down, and "C" brings it to a full halt immediately. "X" can also take it into reverse.

The "Q" key toggles the track from multi-rail to monorail. In 3D it's just a matter of taste, but in 4D the setting you want depends on what you're doing. The multi-rail track can be slow to draw, especially in large scenes, but it's interesting to look at up close, especially at junctions and helices.

Switching

The space bar is also used to control switching. To use it, first point at the tile you want to control. In 3D that's easy enough, but in 4D it can be a bit of a challenge. You'll either need to move around until you're directly above the tile you want to control or switch to non-aligned mode and use the turn keys as a three-dimensional mouse. Either way, it's a good exercise in 4D thinking!

The track starts off all orange. As you switch it, one segment at a time will become red, then when you've gone full circle it will all be orange again. When there's a red segment, trains will choose that segment to move on if they can, otherwise they'll choose at random.

Fisheye

Control-F turns fisheye mode on and off. If you imagine yourself at the center of a cube (in 3D), what fisheye mode does is unfold that cube and show you five of the sides at once, giving you a full 270-degree field of view (where an ideal fisheye lens or a large retina value gives you 180). To put it another way, what you see in the center square is a normal view with the retina set to 1, what you see in the left square is what you'd see if you turned left, and so on.

Similarly, in 4D fisheye mode you see seven of the eight sides of an unfolded tesseract. This is a very good way to think about how much space there is around you!

There are some fisheye options available on the Fisheye tab of the Options screen. The "Enable" option is what you're changing when you press control-F. The "Width" setting controls the width of the side views relative to the center view. The "Rainbow" option turns on double rainbow mode, where the top area shows in-center-out views and the bottom area shows left-center-right views. Ben Blohowiak invented it. It's not my favorite thing, but it's an interesting idea. Ben also had the idea of making the side views flare out, which is awesome!

Also note that you can adjust some of the fisheye settings in game—see Keys tab # 6.

It's a lot of fun playing the maze game in fisheye mode, especially unaligned, and it's addictive to be able to see down side passages without turning to look. On the other hand, fisheye mode definitely interferes with whatever process I use to construct mental maps. All I want to do when it's on is fly around at random.