Add a new type of reference : Line


Instead of having only a box as reference for picture, I can add a "line reference". User can then draw a reference line, be prompted for the real size of this line and draw the line of the object to measure.
This will allow to measure almost anything when you have a reference object wich is not a rectangular thing (kind of a "1 pixel height box").
I will have to make some design changes to implement this... have to think of it more...