Math wizardry

[Roger.E.Eller at sealedair.com]

For anyone interested, the modifications I made to Jim's original function 
will now return a negative or positive angle that can be used to set the 
angle property of an image object. This is great for rotating an image by 
simply drawing a line object at the angle you desire.

function theGeometricalAngle p1,p2
  --Geometrical angle of line defined by the two points p1 and p2
  get the paramcount
  if it is 1 then
    put line 2 of p1 into p2
    put line 1 of p1 into p1
  end if
  put item 1 of p2 - item 1 of p1 into dx
  put item 2 of p2 - item 2 of p1 into dy
  put atan2(dy,dx) into tAngle
  --Add or subtract pi as needed.
  switch
  case  tAngle < 0
    put (tAngle + pi)*(360/pi) into tAngle
    break
  case  tAngle > pi
    put (tAngle - pi)*(360/pi) into tAngle
    break
  default
    put tAngle*(360/pi) into tAngle
  end switch
--Change to negative/positive angle format.
  if (360-tAngle)/2 <= 90 then
    return round((360-tAngle)/2)
  else
    return round(((360-tAngle)/2)-180)
  end if
end theGeometricalAngle

--
Roger Eller <roger.e.eller at sealedair.com>