[alogo] Billiard ball trajectories inside polygons

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Example constructed using the user-tool [FindTrajectory].
The script to produce the tool is contained in the file [BilliardTrajectories] in the scripts-files.

The tool selects the free modifiable objects
a) A closed polygon p
b) Two points A, B inside the polygon
c) A number object N

After that it creates a billiard-ball-trajectory with N vertices (reflection points) on the polygon p. The four selected objects are the masters of the trajectory, hence free modifiable. The trajectory is organized as a group of 2+N points and N segments. The first segment (red) contains the first three elements of the group. The group is organized after the pattern:
pt-pt-pt-seg-pt-seg-pt-seg-pt ... etc. Each segment joining the two, preceding it, points.

To quickly modify the number of sides of the trajectory, select the number-object and use the upper arrow key of the keyboard.
You can only augment the number of sides. For the time being you can't reduce the number of sides. Use the [Undo] if you want to come back to fewer sides.

Produced with EucliDraw©