Solids Builder - Curves

Curves are auxiliary geometries for drawing more complex geometries. There are the following activities that create curves:

• Circle - creates a circle with radius, center and normal vector
• Arc - draws an arc, given center, radius, starting and ending angle
• Ellipse - draws an ellipse, given center, major radius, minor radius, major radius vector, start and end angle
• Line - creates a line that passes through two points
• Polyline - creates a 2D polyline that contains the list of selected points
• 3D Polyline - creates a 3D polyline with the option of rounding the vertices (like a wire)
• 3D Polyline (given list) - creates a 3D polyline with the predefined list of points
• 3D arc - creates a sector of helix with beginning, end and convexity
• Offset - creates an offset curve from another curve (line, polyline, circle)
• Join Lines - Junctions lines, arcs and polylines that have a coincident beginning and ending

Properties (to be used in VB expressions)

• StartPoint - curve start point ( point)
• EndPoint - curve end point ( point)
• Length2D - length of the curve projected in the XY plane (the curve will probably be deformed, so its perimeter will be different from the 3D perimeter of the curve)
• Length - 3D perimeter, or real length of the curve, real number
• EndParam - final curve parameter, real number
• StartParam - Initial parameter, real number

Methods (to be used in VB expressions):

• Get2dCurve() - creates a 2D curve in the XY plane
  
  
• GetPointatDist - calculates a point on the curve, given a distance to travel from the start, just like Point On Curve
  pt = curva. GetPointatDist(distance)
  Where:
  pt will be a Point
  distance is a real number
  
  
• GetPointatParameter - calculates a point on the curve, given a parameter
  pt = curva. GetPointatParameter(param)
  Where:
  pt will be a Point
  param is a real number
• GetClosestPointTo - calculates a point (pt) on the curve that is closest to the given point (pinf)
  pt = curve. GetClosestPointTo(pinf)
  Where:
  pt and pinf are Points
• GetDistatPoint - calculates the 3D distance traveled on the curve until you find the informed point
  distance = curve. GetDistatPoint (pt)
  Where:
  pt is a Point
  distance will be a real number
• GetFirstDerivative - calculates the tangent vector to the curve
  vector = curve. GetFirstDerivative (arg)
  Where:
  arg is a Point, or parameter (real number)
  vector will be a vector
• ReverseCurve - returns a curve in the opposite direction
  reverseCurve = curve. ReverseCurve()
  Where:
  curve and reverseCurve are curves