/// <summary>
/// returns the area of the polyloop
/// </summary>
/// <param name="loop"></param>
/// <returns></returns>
public static double Area(this IfcPolyLoop loop)
{
XbimVector3D sum = new XbimVector3D(0, 0, 0);
IList <IfcCartesianPoint> pts = loop.Polygon;
for (int i = 0; i < pts.Count - 1; i++)
{
XbimVector3D a = new XbimVector3D(pts[i].X, pts[i].Y, pts[i].Z);
XbimVector3D b = new XbimVector3D(pts[i + 1].X, pts[i + 1].Y, pts[i + 1].Z);
sum = sum + a.CrossProduct(b);
}
XbimVector3D n = loop.NewellsNormal();
return(n.DotProduct(sum) / 2);
}
/// <summary>
/// returns the area of the polyloop
/// </summary>
/// <param name="loop"></param>
/// <returns></returns>
public static double Area(this IfcPolyLoop loop)
{
var sum = new XbimVector3D(0, 0, 0);
var pts = loop.Polygon;
for (var i = 0; i < pts.Count - 1; i++)
{
var a = new XbimVector3D(pts[i].X, pts[i].Y, pts[i].Z);
var b = new XbimVector3D(pts[i + 1].X, pts[i + 1].Y, pts[i + 1].Z);
sum = sum + a.CrossProduct(b);
}
var n = loop.NewellsNormal();
return(n.DotProduct(sum) / 2);
}