Affine transformation without augmented matrix
In the attached file (it's a draft, so many things have to be done - have a look at the current selection) I've applied a matrix ((a,b),(c,d)) to points A,B,C, then applied a translation (p,q) to the resulting points A',B',C' to get the final ones A'', B'', C''.
What I don't understand is why the final points are moveable. I can drag them, and the vector (p,q) changes. But (p,q) is defined using direct input, that is 2 values independent by the objects in the construction, so it should stay as it is.
If I save and reopen, the transformed points are where they are supposed to be, but are draggable. I'm probably missing something obvious that I'm totally unable to see, this morning.
Anyone can share some insights? Thank you.