startpt endpt - rotation angle??

[russell84]

if i have a start point and a end point of a line stored how do i get the rotation angle of that line within lisp??

[buddygillespie]

I've not done any lisp for a long while but here is some VBA code that will record the angle of a line. Open or create a drawing with a line in it then

open your VBA editor (Alt F11) and create a new module and add the following sub LineTest to the module and run it.

 

Public Sub LineTest()
Dim oAcEntity As AcadEntity
Dim oAcLine As AcadLine

 'search all entities for a line object
 For Each oAcEntity In ThisDrawing.ModelSpace
   'find the 1st line object in the current drawing
   If oAcEntity.ObjectName = "AcDbLine" Then
     'record the line
     Set oAcLine = oAcEntity
     Exit For
   End If
 Next
 
 'declare a variable to hole the line angle
 Dim ThisLineAngle As Double
 'convert radians to degrees
 ThisLineAngle = oAcLine.Angle * 180# / 3.14159265
 'print the value
 Debug.Print ThisLineAngle
End Sub

Hope this works for you. I'm sure someone will send you a lisp reply...

[lpseifert]

if i have a start point and a end point of a line stored how do i get the rotation angle of that line within lisp??

(angle pt1 pt2)

where pt1 and pt2 are star and end points in (x y z) list form. This will give you the angle in radians relative to the current UCS.

[russell84]

yes thanks kindly - i dont have the help guide here at home..cheers for that

 

i ended up using

 

(setq a (list (car startpt)(cadr startpt)))
(setq b (list (car endpt)(cadr endpt)))
(setq ANG (angle a b))

 

Cheers mate

[TimSpangler]

yes thanks kindly - i dont have the help guide here at home..cheers for that

 

i ended up using

 

(setq a (list (car startpt)(cadr startpt)))
(setq b (list (car endpt)(cadr endpt)))
(setq ANG (angle a b))

 

Cheers mate

 

If a and b are nothing more than place holders then do this instead:

 

(setq ANG 
 (list (car startpt)(cadr startpt))
 (list (car endpt)(cadr endpt))
)

 

If you are using them later then the way you have it is fine.

 

$.02