Climber Work

Worked on the climber algorithms tonight.

For a ribbon segment without a climber or other ribbon furniture, the forces on the ribbon follow Hook's law, where the distance between the start point of two ribbon segments is compared against the initial segment length to compute the forces exhibited by the two segments on each other.

For a segment with a climber, I break the ribbon segment into two pieces, one 'below' the climber and the other 'above' the climber. If I can accurately state what the initial length of each of the pieces of the resulting ribbon is, then I can compute the forces on the ribbon segments and climber by calling the simple ribbon segment dynamics. I've already developed the method that checks when a climber has transitioned from one segment to the next. The missing pieces are computing the force that the climber applies to the ribbon, computing the amount of 'initial length' of the ribbon that the climber will cross in a simulation time increment, and to modify the old climber dynamics routine to the use the new methods.