/// <summary>
/// Extrudes a polygon.
/// </summary>
/// <param name="polygon">The polygon to extrude</param>
/// <param name="distance">Extrusion distance</param>
/// <param name="normal">Optional normal to extrude along, default is polygon normal</param>
/// <returns></returns>
public static List <Polygon> extrudePolygon(Polygon polygon, float distance, Vector3?normal = null)
{
normal = normal != null ? normal : polygon.plane.normal;
Vector3 du = normal.GetValueOrDefault();
Vertex[] vertices = polygon.vertices;
List <Vertex> top = new List <Vertex>();
List <Vertex> bot = new List <Vertex>();
List <Polygon> polygons = new List <Polygon>();
Vector3 invNormal = normal.GetValueOrDefault();
du *= distance;
invNormal *= -1f;
for (int i = 0; i < vertices.Length; i++)
{
int j = (i + 1) % vertices.Length;
Vector3 p1 = vertices[i].position;
Vector3 p2 = vertices[j].position;
Vector3 p3 = p2 + du;
Vector3 p4 = p1 + du;
Plane plane = Plane.fromPoints(p1, p2, p3);
Vertex v1 = new Vertex(p1, plane.normal);
Vertex v2 = new Vertex(p2, plane.normal);
Vertex v3 = new Vertex(p3, plane.normal);
Vertex v4 = new Vertex(p4, plane.normal);
Polygon poly = new Polygon(new List <Vertex>(new Vertex[] { v1, v2, v3, v4 }), polygon.shared);
polygons.Add(poly);
top.Add(new Vertex(p4, normal.GetValueOrDefault()));
bot.Insert(0, new Vertex(p1, invNormal));
}
polygons.Add(new Polygon(top, polygon.shared));
polygons.Add(new Polygon(bot, polygon.shared));
return(polygons);
}
public Polygon(List <IVertex> vertices, System.Object shared)
{
this.vertices = vertices.ToArray();
this.shared = shared;
this.plane = Plane.fromPoints(vertices[0].pos, vertices[1].pos, vertices[2].pos);
}
public Polygon(List <IVertex> vertices)
{
this.vertices = vertices.ToArray();
this.plane = Plane.fromPoints(vertices[0].pos, vertices[1].pos, vertices[2].pos);
}
public Polygon(IVertex[] vertices, System.Object shared)
{
this.vertices = vertices;
this.shared = shared;
this.plane = Plane.fromPoints(vertices[0].pos, vertices[1].pos, vertices[2].pos);
}
public Polygon(IVertex[] vertices)
{
this.vertices = vertices;
this.plane = Plane.fromPoints(vertices[0].pos, vertices[1].pos, vertices[2].pos);
}