GOAL |
Your GOAL is to make this 2D framework rigid. Click mouse and buttons, or tap console keys to choose and brace/unbrace tiles. Toggle mode to check rigidity by choosing and shifting ribbons. The carpet is rigid if a shift along EVERY ribbon rigidly rotates the carpet. |
CONTROLS
Toggle choose/brace modes: | Choose tile: | Toggle brace/unbrace: | To choose ribbons: |
Tap or click (v) key or button. | Click mouse on it or travel to it with (j)(k) keys or buttons. | Click mouse or toggle with (spacebar) key or button | .Travel to it with (j)(k) keys or buttons. |
SOLUTION
The graph (on the right) represents the intersections between ribbons. Each vertex corresponds to a ribbon. The edges connecting two vertices represents the intersection of those two ribbons. When the face at an intersection is braced, the edge in the graph representing that intersection turns red. The carpet is rigid when the Wester Graph (red) is connected and spanning.