toNurbsCurve(Arc) and Tranform(NurbsCurve)

Implemented toNurbsCurve(Arc) and Tranform(NurbsCurve) fixes #960
BHoM · May 16, 2019 · 6b61e94 · 6b61e94
1 parent 57027ae
commit 6b61e94
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Showing 2 changed files with 19 additions and 4 deletions.
diff --git a/Geometry_Engine/Convert/NurbsForm.cs b/Geometry_Engine/Convert/NurbsForm.cs
@@ -34,10 +34,21 @@ public static partial class Convert
         /**** Public  Methods - Curves                  ****/
         /***************************************************/
 
-        [NotImplemented]
         public static NurbsCurve ToNurbsCurve(this Arc arc)
         {
-            throw new NotImplementedException();
+            Point P0 = arc.StartPoint();
+            Point P2 = arc.EndPoint();
+            Point M = Query.Average(new List<Point>() { P0, P2 });
+            Point O = arc.CoordinateSystem.Origin;
+
+            double a = Math.PI/2 - Query.Angle(P0 - O, M - O);
+            Point P1 = O + (M - O).Normalise() * arc.Radius / Math.Sin(a);
+
+            return new NurbsCurve() {
+                ControlPoints = new List<Point>() { P0, P1, P2 },
+                Weights = new List<double>() { 1, Math.Sin(a), 1 },
+                Knots = new List<double>() { 0, 0, 1, 1 }
+            };
         }
 
         /***************************************************/

diff --git a/Geometry_Engine/Modify/Transform.cs b/Geometry_Engine/Modify/Transform.cs
@@ -113,10 +113,14 @@ public static Line Transform(this Line line, TransformMatrix transform)
 
         /***************************************************/
 
-        [NotImplemented]
         public static NurbsCurve Transform(this NurbsCurve curve, TransformMatrix transform)
         {
-            throw new NotImplementedException();
+            return new NurbsCurve()
+            {
+                ControlPoints = curve.ControlPoints.Select(cp => cp.Transform(transform)).ToList(),
+                Weights = curve.Weights,
+                Knots = curve.Knots
+            };
         }