/// <summary>
/// Apply opening polygons on contour polygons, with triangulation
/// </summary>
private static void _cutOpenings(List <Point3DCollection> surfVertices,
IEnumerable <List <Point3DCollection> > openingVertices,
out Point3DCollection vertices,
out Int32Collection indices)
{
vertices = new Point3DCollection();
indices = new Int32Collection();
var tes = new LibTessDotNet.Double.Tess();
foreach (var poly in surfVertices)
{
var cont = poly.Select(pt => new ContourVertex(new Vec3(pt.X, pt.Y, pt.Z))).ToArray();
tes.AddContour(cont, ContourOrientation.CounterClockwise);
}
foreach (var opening in openingVertices)
{
foreach (var poly in opening)
{
var hole = poly.Select(pt => new ContourVertex(new Vec3(pt.X, pt.Y, pt.Z))).ToArray();
tes.AddContour(hole, ContourOrientation.Clockwise);
}
}
tes.Tessellate();
vertices = new Point3DCollection(tes.Vertices.Select(i => new Point3D(i.Position.X, i.Position.Y, i.Position.Z)));
indices = new Int32Collection(tes.Elements);
}
/// <summary>
/// Create viewport geometry for the polygons (with tesselation)
/// </summary>
private static List <GeometryModel3D> _geometryFromPolygons(List <Point3DCollection> polyList)
{
var geomList = new List <GeometryModel3D>();
foreach (var poly in polyList)
{
var tes = new LibTessDotNet.Double.Tess();
tes.AddContour(poly.Select(pt => new ContourVertex(new Vec3(pt.X, pt.Y, pt.Z))).ToArray());
tes.Tessellate();
var positions = new Point3DCollection(tes.Vertices.Select(i => new Point3D(i.Position.X, i.Position.Y, i.Position.Z)));
var triangleIndices = new Int32Collection(tes.Elements);
var material = MaterialHelper.CreateMaterial(Colors.LightGray); // Just in case, not to accidentally remain invisible (consequence of null)
var mesh = new MeshGeometry3D()
{
Positions = positions,
TriangleIndices = triangleIndices
};
var geom = new GeometryModel3D()
{
Geometry = mesh,
Material = material,
BackMaterial = null
};
geomList.Add(geom);
}
return(geomList);
}