Tile-Moving Explorer

This program lets you explore a certain type of tile-moving puzzle.

The goal of the tile-moving puzzles simulated by this program is to change one pattern into another by moving square tiles around on a grid. When a tile is moved, at least two of its edges must touch the edges of other tiles.

How to use this program:

This program starts in "edit mode". Use the Edit check box to toggle edit mode on and off. While in edit mode, you can click on the grid cells to insert or remove tiles. Use edit mode to enter the starting tile pattern by clicking on the cells. The Initialize button removes all of the tiles. Use the Size slider to change the number of cells that appear in the grid when the puzzle is initialized.

Uncheck the Edit check box to try out a puzzle. To move a tile, click on it. The tile, and all legal destination cells, will become highlighted. Click on one of the destination cells to move the tile. Keep moving the tiles until you reach the final pattern or get stuck.

Your moves are recorded in the History panel. The first line in the panel will record the position of the first tile in the initial pattern (the tile that is furthest left in the highest row). This information lets people know how your initial tile pattern was positioned in the grid. Each move is recorded as four numbers. The first two numbers are the coordinates of the moved tile's starting location (row number and column number). The second two numbers are the coordinates of the tile's ending location.

To copy your solution into a file, click on the Copy button, and press Ctrl-C to copy the text into your copy buffer. You can also transfer your solutions to other documents by selecting text in the History panel and using cut and paste techniques.

Whenever the mouse is passed over a cell, the cell's coordinates are shown in the At: field.

The Back button undoes previous moves. The Forward button redoes the moves. Press the Restart button to start at the beginning. You can use the Forward button after pressing Restart to review your moves graphically.

An example puzzle (fairly tricky)::

With the size set to 4 (for a 4 by 4 grid), change the pattern shown on the left into the pattern shown on the right.