Create polylines with the starting point selected at the end of the program

[Isaac26a]

Hi friends, I hope you can help me to solve this question that I have, I want to create a polyline or a line with entmake but, let's say I want to create a the next polyline with the following points ( (1,1,0) (2,2,0) (6,5,0)) that is kind of simple, but I want this polyline start from a selected point at the end of the program, I mean is like a polyline created like a ghost, and defined at the end when you pick the starting point, so if I pick the point (10,10,0) the polyline becomes ((10,10,0) (11,11,0) (15,14,0)). I have seen programs that do that but I still don't know how to, thanks in advance for your help

[Jonathan Handojo]

Alright... so then I'm assuming that ((1,1,0) (2,2,0) (6,5,0)) are the "vectors" of the polyline indicating the direction of where the polyline shall be drawn... and then you want to click a point somewhere to draw the polyline in that exact direction from the picked point.

 

Assuming that you already obtained vec = ((1,1,0) (2,2,0) (6,5,0)) and pt = (10,10,0), you can get the list of points of your polyline using the below:

(mapcar '(lambda (x) (mapcar '+ x pt)) vec)

 

Hopefully that will give you a start and then be able to make your 'ghost' polyline.

[Isaac26a]

11 hours ago, Jonathan Handojo said:

Hopefully that will give you a start and then be able to make your 'ghost' polyline.

Thank you Jonathan Handojo, didn't know about grvecs, I think now I have homework to do.