Transformation of form

Hallo again!

What I need: To make such transformation of basic L-shape.

And what's your problem, hah?: And my problem is that according to my knowdelge of grass I decided to nake by *path1 and want to know, is it efficient way? or there is any way to put like in animation three keyshots and make transformation go?

My path1*: draw projections - lines with the lenght i need on xy plane. then extract points and give them appropriate z value. Then join this points and so on.