///
/// Applies the specified transformation to this polygon.
///
/// <b>Note:</b> if the applied transformation performs a mirror operation
/// the vertex order of this polygon is reversed.
///
/// <param name="transform">the transformation to apply</param>
///
/// <returns>this polygon</returns>
///
public Polygon transform(Transform transform)
{
this.vertices.ForEach(
(v) => {
v.transform(transform);
}
);
IVector3d a = this.vertices[0].pos;
IVector3d b = this.vertices[1].pos;
IVector3d c = this.vertices[2].pos;
this._csg_plane.normal = b.minus(a).crossed(c.minus(a)).normalized();
this._csg_plane.dist = this._csg_plane.normal.dot(a);
this.plane = CSharpVecMath.Plane.
fromPointAndNormal(centroid(), _csg_plane.normal);
vertices.ForEach((vertex) => {
vertex.normal = plane.getNormal();
});
if (transform.isMirror())
{
// the transformation includes mirroring. flip polygon
flip();
}
return(this);
}
/// <summary>
/// Flips this polygon.
/// </summary>
/// <returns>this polygon</returns>
///
public Polygon flip()
{
vertices.ForEach((vertex) => {
vertex.flip();
});
vertices.Reverse();
_csg_plane.flip();
this.plane = plane.flipped();
return(this);
}
/// <summary>
/// Constructor. Creates a new polygon that consists of the specified
/// vertices.
///
/// <b>Note:</b> the vertices used to initialize a polygon must be coplanar
/// and form a convex loop.
/// </summary>
/// <param name="vertices">polygon vertices</param>
///
public Polygon(List <Vertex> vertices)
{
this.vertices = vertices;
this._csg_plane = Plane.createFromPoints(
vertices[0].pos,
vertices[1].pos,
vertices[2].pos);
this.plane = CSharpVecMath.Plane.
fromPointAndNormal(centroid(), _csg_plane.normal);
validateAndInit(vertices);
}
/// <summary>
/// Translates this polygon.
/// </summary>
/// <param name="v">the vector that defines the translation</param>
/// <returns>this polygon</returns>
///
public Polygon translate(IVector3d v)
{
vertices.ForEach((vertex) => {
vertex.pos = vertex.pos.plus(v);
});
IVector3d a = this.vertices[0].pos;
IVector3d b = this.vertices[1].pos;
IVector3d c = this.vertices[2].pos;
// TODO plane update correct?
this._csg_plane.normal = b.minus(a).crossed(c.minus(a));
this.plane = CSharpVecMath.Plane.
fromPointAndNormal(centroid(), _csg_plane.normal);
return(this);
}
