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, start and end angle
• Arc by Points - draws an arc, given 3 points
• Ellipse - draws an ellipse, given center, major radius, minor radius, major radius vector, start and end angle
• Line - creates a line passing through two points
• Polyline - creates a 2D polyline containing the list of selected points
• Rectangle - creates rectangle at the given point and direction
• Polyline 3D - creates a 3D polyline with the option of rounding the vertices (like a wire)
• Arc 3D - creates a helix sector with start, end and convexity
• Offset - creates an offset curve from another curve (line, polyline, circle)
• Join Lines - Junctions lines, arcs and polylines that have coincident start and end
• Trim Lines - Trims a line, like AutoCAD's TRIM command
• Spline - creates a 3D spline

Properties (for use in VB expressions)

• StartPoint - starting point of the curve ( point)
• EndPoint - endpoint of the curve ( 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 curve length, real number
• EndParam - end parameter of the curve, real number
• StartParam - Start parameter, real number

Methods (for use 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, such as Point on the Curve
  pt = curve. GetPointAtDist(distance)
  Where:
  pt will be an Point
  distance is a real number
  
  
• GetPointAtParameter - calculates a point on the curve, given a parameter
  pt = curve. GetPointAtParameter(param)
  Where:
  pt will be an 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 will be a Point
• GetDistAtPoint - calculates the 3D distance traveled on the curve until reaching the given point
  distance = curve. GetDistAtPoint (en)
  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 an Point, or the parameter (real number)
  vector will be an vector
• ReverseCurve - returns a curve in the opposite direction
  reversecurve = curve. ReverseCurve()
  Where:
  curve and reversecurve are curves