Algodoo

hrmmmm....

(delete this comment)

Good job, but if you try to move mirrors, it sometimes go through them, or through other objects.
I made a simple box and it enters inside before being refracted, so if the object isn't thick, it will go through it without being refracted (I don't know if refracted is the good term but you understand what I mean).

Anyway, it seems to work fine, this apart.

EDIT : It doesn't work with circles

good job but is it normal that a laser beam has an energy of 0 joule

The circles sometimes go out of control and get launched randomly and everywhere.
fix it