Paths on a surface 
On the plane?
Instructions
In the figure we have represented two planar paths.
At the vertical bar we can select one of the following actions:
- Move points: To modify the paths drag the marked points.
- Close paths: Each path on the grid is completed by adding one shortest segment from the initial to the final points of the path.
- See deformation: We can bserve a continuous deformation from one path to the other. To control this animation drag the point on the bar of the right.
