curve planari

[Lulla]

hi to all..I have a problem with the curves planari after drawing them, I send but disappear! how can I solve?

 

[paolino]

Hi.
I don't think I understand, what do you mean by planar curves? . . .
if you are simply tracking a segment with the line command, you have to click the mouse left on the initial point and then also on the final point, then you can press Enter to exit the command.. .