public CylinderParams GetBoundingCylinder(IBody2 body, double[] dir) { double[] xAxis = new double[] { 1, 0, 0 }; double[] yAxis = new double[] { 0, 1, 0 }; double[] zAxis = new double[] { 0, 0, 1 }; bool isAligned = m_MathHelper.ArrayEqual(dir, yAxis); IMathTransform alignTransform = null; if (!isAligned) { alignTransform = m_MathHelper.GetTransformBetweenVectorsAroundPoint( dir, yAxis, new double[] { 0, 0, 0 }); IBody2 bodyCopy = body.ICopy(); bodyCopy.ApplyTransform(alignTransform as MathTransform); body = bodyCopy; } double[] rootPt; double[] endPt; GetExtremePoints(body, yAxis, out rootPt, out endPt); double height = Math.Abs(endPt[1] - rootPt[1]); dir = new double[] { 0, endPt[1] - rootPt[1], 0 }; List <double[]> perPoints = GetPerimeterPoints(body, xAxis, zAxis); List <Point> points = new List <Point>(); foreach (double[] pt in perPoints) { points.Add(new Point(pt[0], pt[2])); } Circle cir = SmallestEnclosingCircle.MakeCircle(points); double[] circCenter = new double[] { cir.c.x, rootPt[1], cir.c.y }; if (!isAligned) { circCenter = m_MathHelper.TransformPoint(circCenter, alignTransform.IInverse()); dir = m_MathHelper.TransformVector(dir, alignTransform.IInverse()); } double radius = cir.r; return(new CylinderParams(height, circCenter, dir, radius)); }