public static BSplineSurface GetBSplineSurfaceParams(this ISurface swSurf, double tol)
{
var swSurfParameterisation = swSurf.Parameterization2();
bool sense;
var surfParams = swSurf.GetBSurfParams3(false, false, swSurfParameterisation, tol, out sense);
var uKnotVector = surfParams.UKnots.CastArray <double>();
var vKnotVector = surfParams.VKnots.CastArray <double>();
// Yeah it is flipped. I know. Don't switch it back. BPH
var controlPointArray = new Vector4[surfParams.ControlPointColumnCount, surfParams.ControlPointRowCount];
Enumerable.Range(0, surfParams.ControlPointRowCount)
.ForEach(u =>
{
Enumerable.Range(0, surfParams.ControlPointColumnCount)
.ForEach(v =>
{
var array = surfParams.GetControlPoints(u + 1, v + 1).CastArray <double>();
var x = array[0];
var y = array[1];
var z = array[2];
var w = 1.0;
if (surfParams.ControlPointDimension == 4)
{
w = array[3];
}
var ctrlPoint = new Vector4(x * w, y * w, z * w, w);
controlPointArray[v, u] = ctrlPoint;
});
});
return(new BSplineSurface
(controlPointList: controlPointArray
, orderU: surfParams.UOrder
, orderV: surfParams.VOrder
, knotsU: uKnotVector
, knotsV: vKnotVector
, surfaceDimension: surfParams.ControlPointDimension
, uIsPeriodic: surfParams.UPeriodicity
, vIsPeriodic: surfParams.VPeriodicity
));
}