Using the applet:
- the black circle is the eyepoint
- as you move it around with the mouse, the current cell will be highlighted
- you can also insert/move line segments which will split the appropriate BSP leaves
- the positive half-space side of the segments will be colored lighter than the back side
- the line segments (or their parts) will be labeled with red numbers depending on the order in which they should be drawn
- commands:
- left-down + drag -- move either the eye, a segment, or a segment endpoint, depending on where you click
- right-button-down -- start creating a segment (set first endpoint)
- mouse drag -- move the second endpoint around (only if you've set the first endpoint)
- right-button-up -- finish creating the segment (set second endpoint)
- key 'o' or 'O' -- show / hide the ordering numbers of the segments
- i didn't have patience to implement leaf-level insertion
- source code