How many lines in 3-space intersect 4 given lines in general position? Answer...
Toggle some partitions to activate them.
Define the active partitions.
Press "Process". Puzzles will be created (as surfaces embedded in 4d).
They can be selected by left-clicking on the buttons in the lower section. The "∅" button is a template, numbered buttons are individual puzzles, the "S" button is a panoramic view (left-click on the picture to go from/to it).
Drag with the mouse/right-button to 3d-rotate the picture.
Use ``Sizes'' and ``Tiles'' to vary those features of puzzles (before processing).
Use ``Controls'' for various preset views and keyboard shortcuts.
You can also browse the examples in the ``Examples'' section.
canvas wobbling a bit
line numbering is buggy with double puzzles or partial puzzles
Resizing only works with certain browsers
Try building puzzles yourself! (alpha)
Left click to select tiles at bottom, right click to unselect.
For easier editing, turn on ``Points'' in toggle view, and use views 0 or 1.
No erasing (but can undo last tile with middle button), only one editable puzzle at a time.
(turn on frame and green line numbering)
(turn on frame and red line numbering)
(move a bit to 0 or 1, or use edge numbering)
(move a bit to 7 or 8, or use dual edge numbering)
puzzle rotated 180°
rotate 90° in the plane orthogonal to the projection plane
← and → for previous/next puzzle, ↑ and ↓ for previous/next series.
Enable keyboard shortcuts
(prevents normal keyboard behavior)
Switch left and right mouse buttons
(or switch touch behavior)