Burr6 Java Applet Help

The Burr6 Java applet, to display and build your own burr puzzles, runs in either display or build mode. When it comes up initially it is in display mode showing the solution to a particular 6-piece burr.

Display mode

The display mode is shown in the picture below. It allows you to explore and manipulate the puzzle and its solutions. It starts out in an isometric view, but you can also switch it to a smooth VRML mode which allows you to rotate the puzzle by grabbing it with the mouse and dragging it in the direction you want to rotate the puzzle.

To explore the interior construction of the puzzle you may suppress the drawing of pieces and enclosures.

Use the Next/Previous move buttons to see how the puzzle is taken apart.

To switch to build mode click on any of the pieces. You will then be able to change the pieces and have the applet calculate new solutions or cancel out to come back to the display mode.

Build mode

The picture to the left shows the build mode of the applet. Here you can edit the pieces by clicking on the cube symbols below each piece to place or remove a given cube. The applet will keep track of the type of pieces. Once there are no disjoint pieces and the weight of all pieces is less than or equal to 32 the "Calculate" button becomes active. Pressing the calculate button starts the calculation.

There are a number of options at the bottom of the applet:

  • Max calc time per solution (in minutes):
    Some assemblies take extremely long to calculate. This gives you the option to limit the time the applet spends in trying to take an assembly apart. Note: if a set of pieces has 10 assemblies the applet will stop after at most 10 times your timeout value. The default value is 2 minutes.
  • Find first solution only:
    Some sets of pieces have many solutions. Selecting this option will terminate the calculations after the first solution is found. By default this option is off so that all solutions get calculated.
  • Find minimal level:
    When a solution is found, it is not necessary the minimal level solution for a given assembly. Selecting this option will continue the calculations until the minimal level is found. By default this option is off to minimize the compute time.
  • Piece Length:
    Solutions may vary greatly with piece length. This option allows you to specify the most common length of pieces used to make burrs (6, 8, 10, and 12). The default length is 6.
  • Enclose:
    Burr puzzles may be enclosed into different types of cages. You can select among four types: Cube - the burr is completely enclosed into a cube. Box - same as the cube but without the 8 interior cubelets in the corners. Ring - a larger box without the top and bottom of the box. Glass - like a ring but with a bottom added to allow calculation of puzzles like Cutler's Bin-Cross. Note: for the Ring and Box, the piece length should be 8.

    Also note that for Ring and Glass enclosures the code will not always correctly find the solutions. Since the enclosures do not have the same number of symmetries solutions might be missed. If no solution is found switch the first piece around to see if there are other assemblies, with the first piece not in the A position.