I am sure there is a very basic answer to this, but I can’t seem to find it.
I need to draw a perpendicular line at a fixed point on a curve. There is the “Line perpendicular to a curve” function which keeps the line perpendicular to the curve, but I can’t work out how to fix the start point of the line to a specific point on the curve eg. 300mm from the start.
So if I need to draw a 500mm line perpendicular to the original curve, with a starting point exactly 300mm from the start of that original curve. The 500mm part is easy to input, but I can’t find a function to control the start point.
not sure if any of the options of _line can do this.
to find the precise point
_divide the initial curve by _length
click on the curve / arrows if the direction / start / endpoint does not match.
to draw the line
start drawing a standard _line
pick the startpoint.
use the objectsnap _PerpendicularFrom
(pick the curve again, pick the startpoint again)
now you should get a temporary guide perpendicular to the curve.
alternative to the _PerpendicularFrom Snap
you can also turn on Smarttrack, it should show a guide “onPerp” after you picked the first point.
(smartrack is a Button/field at the top of the window - Gridsnap, Ortho, Planar, Smarttrack )
check the help for above commands to get even more background info.
Heh - on the fly this is not exactly straightforward… probably easiest is to mark the point using SubCrv > Mode=MarkEnds and give it the length you want. This can be done on the fly within the command like so, but I am not sure it is worth it:
Start Line > Perpendicular > PointOnCurve… but instead of selecting the curve, type SubCrv, then select the curve and then type in your distance and snap to the end of that sub curve.