Possibly outdated, since we've switched to snap and added new parameters.

• stepsPerSecond: number of simulation steps for gloss to take for each second of real time
• picWidth, picHeight: canvas dimensions
• stepFlag: turns stepping the simulation on and off for debugging (no stepping = objects don't move)
• clampFlag: turns clamping gradient values on and off for debugging
• debug: turns on/off the debug print functions
• constraintFlag: turns constraint satisfaction on/off (currently off because we're doing unconstrained optimization)
• Default ambient objective functions are specified in ambientObjFns, and analogously for ambientConstrFns.
• Default objective functions are specified in genObjsAndFns.
• btls: turn on/off the backtracking line search for debugging (off = use a fixed timestep specified in the code)
• alpha and beta: parameters for the backtracking line search (see code for a more detailed description)
• stopEps: stopping condition sensitivity for gradient descent. Stop when magnitude of gradient is less than stopEps.