/// <summary>
/// Extracts the polygonal faces from the given mesh and returns them
/// as an array of Polygons.
/// </summary>
/// <returns>Array of Polygons.</returns>
public DSPolygon[] ExtractPolygon()
{
int nFaces = FaceIndices.Length;
List <IPolygonEntity> polygons = new List <IPolygonEntity>();
for (int iFace = 0; iFace < nFaces; ++iFace)
{
int nVerts = FaceIndices[iFace].Length;
IPointEntity[] vertices = new IPointEntity[nVerts];
for (int i = 0; i < nVerts; ++i)
{
vertices[i] = Vertices[FaceIndices[iFace][i]].PointEntity;
}
IPolygonEntity polygon = HostFactory.Factory.PolygonByVertices(vertices);
if (null == polygon)
{
continue;
}
polygons.Add(polygon);
}
return(polygons.ToArray().ToArray <DSPolygon, IPolygonEntity>(true)); //don't persist returned polygons.
}
/// <summary>
/// Returns trimmed polygon after trimming this polygon using the
/// given array of planes as half spaces.
/// </summary>
/// <param name="halfSpaces">Trimming planes.</param>
/// <returns>Trimmed Polygon</returns>
public Polygon Trim(Plane[] halfSpaces)
{
IPlaneEntity[] hosts = halfSpaces.ConvertAll(GeometryExtension.ToEntity <Plane, IPlaneEntity>);
IPolygonEntity entity = PolygonEntity.Trim(hosts);
if (null == entity)
{
return(null);
}
Hide(this);
Hide(halfSpaces);
return(new Polygon(entity, true));
}
void Onbuild(IPolygonEntity polyEntity)
{
var polyObj = new GameObject();
var polyView = polyObj.AddComponent <PolygonView>();
polyObj.transform.parent = contextView.transform;
polyObj.name = "Polygon_" + polyCount++;
var lineParentObj = new GameObject("LineGroup");
lineParentObj.transform.parent = polyObj.transform;
polyView.lineParent = lineParentObj.transform;
var pointParentObj = new GameObject("PointGroup");
pointParentObj.transform.parent = polyObj.transform;
polyView.pointParent = pointParentObj.transform;
int count = polyEntity.Points.Count;
polyView.points = new List <PointView> ( );
polyView.lines = new List <LineView> ( );
var pointViews = polyEntity.Points.Select(p => pointPrefab.Spawn(p.position)).ToArray();
for (int i = 0, j = 1; i < count; i++, j = (i + 1) % count)
{
var entity = polyEntity.Points[i];
var pointView = pointViews[i];
pointView.transform.parent = polyView.pointParent;
var lineView = linePrefab.Spawn();
lineView.transform.parent = polyView.lineParent;
lineView.startPoint = pointViews [i];
lineView.endPoint = pointViews [j];
lineView.curvePosition = entity.curvePosition;
lineView.OnRender( );
polyView.points.Add(pointView);
pointView.poly = polyView;
polyView.lines.Add(lineView);
lineView.poly = polyView;
}
lookup.libs.Add(polyView, polyEntity);
}
/// <summary>
/// 仅取外轮廓的 关键点 与 曲率点 为 顶点（不再新增三角网格顶点），所构建的网格；
/// </summary>
/// <param name="polyEntity"></param>
/// <returns></returns>
public static TriangleNet.Mesh BaseTriangleMesh(this IPolygonEntity polyEntity)
{
int count = polyEntity.Points.Count;
var triPolygon = new Polygon();
var vertices = new Vertex[count * 2];
for (int i = 0; i < count; i++)
{
var point = polyEntity.Points[i];
vertices [2 * i] = new Vertex(point.position.x, point.position.y, i);
vertices [2 * i + 1] = new Vertex(point.curvePosition.x, point.curvePosition.y, i);
}
var contour = new Contour(vertices);
triPolygon.Add(contour);
return((TriangleNet.Mesh)triPolygon.Triangulate( ));
}
public static TriangleNet.Mesh GetTriangleMesh(this IPolygonEntity polyEntity, float segmentLength = 0.1F)
{
int count = polyEntity.Points.Count;
var triPolygon = new Polygon();
for (int i = 0, j = 1; i < count; i++, j = (i + 1) % count)
{
var curPoint = polyEntity.Points[i];
var nextPoint = polyEntity.Points[j];
var dis = curPoint.DistanceTo(nextPoint);
var num = (int)(dis / segmentLength);
int id = i + 1;
var segments = curPoint.SplitToSegments(nextPoint, num).Select(p => new Vertex(p.x, p.y, id)).ToArray();
for (int m = 0, n = 1; m < segments.Count( ) - 1; m++, n = m + 1)
{
triPolygon.Add(new Segment(segments [m], segments [n], id), 0);
}
}
//等边三角形面积公式 ： S=√3a²/4; √3/4 = 0.443F;
var area = 0.443F * segmentLength * segmentLength;// * 1.25F;
var options = new ConstraintOptions()
{
ConformingDelaunay = true
};
var quality = new QualityOptions()
{
MinimumAngle = 30F, MaximumArea = area
}; // 0.2F };
var triMesh = (TriangleNet.Mesh)triPolygon.Triangulate(options, quality);
triMesh.Renumber( );
return(triMesh);
}
private static IPolygonEntity ByVerticesCore(Point[] vertices)
{
IPointEntity[] hosts = vertices.ConvertAll(GeometryExtension.ToEntity <Point, IPointEntity>);
if (hosts.Length <= 2)
{
throw new System.ArgumentException(string.Format(Properties.Resources.LessThan, "number of vertices", "3"), "vertices");
}
if (hosts.ArePointsColinear())
{
throw new System.ArgumentException(string.Format(Properties.Resources.PointsColinear, "vertices"), "vertices");
}
IPolygonEntity entity = HostFactory.Factory.PolygonByVertices(hosts);
if (null == entity)
{
throw new System.Exception(string.Format(Properties.Resources.OperationFailed, "Polygon.ByVertices"));
}
return(entity);
}
private Polygon(IPolygonEntity host, bool persist = false) : base(host, persist)
{
InitializeGuaranteedProperties();
}
private DSPolygon(IPolygonEntity host, bool persist = false)
: base(host, persist)
{
InitializeGuaranteedProperties();
}
