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02: TriangulationPoint's edges
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+401
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‎Triangulation/Delaunay/DelaunayTriangle.cs‎

Lines changed: 204 additions & 186 deletions
Original file line numberDiff line numberDiff line change
@@ -27,189 +27,207 @@
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* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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/// Changes from the Java version
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/// attributification
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/// Future possibilities
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/// Flattening out the number of indirections
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/// Replacing arrays of 3 with fixed-length arrays?
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/// Replacing bool[3] with a bit array of some sort?
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/// Bundling everything into an AoS mess?
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/// Hardcode them all as ABC ?
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using System;
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using System.Diagnostics;
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using System.Collections.Generic;
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namespace Poly2Tri {
46-
public class DelaunayTriangle {
47-
public FixedArray3<TriangulationPoint> Points;
48-
public FixedArray3<DelaunayTriangle > Neighbors;
49-
public FixedBitArray3 EdgeIsConstrained, EdgeIsDelaunay;
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public bool IsInterior { get; set; }
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public DelaunayTriangle(TriangulationPoint p1, TriangulationPoint p2, TriangulationPoint p3) {
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Points[0] = p1;
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Points[1] = p2;
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Points[2] = p3;
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}
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public int IndexOf(TriangulationPoint p) {
59-
int i = Points.IndexOf(p);
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if (i==-1) throw new Exception("Calling index with a point that doesn't exist in triangle");
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return i;
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}
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public int IndexCWFrom (TriangulationPoint p) { return (IndexOf(p)+2)%3; }
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public int IndexCCWFrom(TriangulationPoint p) { return (IndexOf(p)+1)%3; }
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public bool Contains(TriangulationPoint p) { return Points.Contains(p); }
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/// <summary>
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/// Update neighbor pointers
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/// </summary>
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/// <param name="p1">Point 1 of the shared edge</param>
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/// <param name="p2">Point 2 of the shared edge</param>
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/// <param name="t">This triangle's new neighbor</param>
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private void MarkNeighbor( TriangulationPoint p1, TriangulationPoint p2, DelaunayTriangle t ) {
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int i = EdgeIndex(p1,p2);
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if ( i==-1 ) throw new Exception( "Error marking neighbors -- t doesn't contain edge p1-p2!" );
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Neighbors[i] = t;
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}
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/// <summary>
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/// Exhaustive search to update neighbor pointers
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/// </summary>
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public void MarkNeighbor( DelaunayTriangle t ) {
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// Points of this triangle also belonging to t
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bool a = t.Contains(Points[0]);
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bool b = t.Contains(Points[1]);
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bool c = t.Contains(Points[2]);
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if (b&&c) { Neighbors[0]=t; t.MarkNeighbor(Points[1],Points[2],this); }
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else if (a&&c) { Neighbors[1]=t; t.MarkNeighbor(Points[0],Points[2],this); }
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else if (a&&b) { Neighbors[2]=t; t.MarkNeighbor(Points[0],Points[1],this); }
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else throw new Exception( "Failed to mark neighbor, doesn't share an edge!");
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}
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/// <param name="t">Opposite triangle</param>
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/// <param name="p">The point in t that isn't shared between the triangles</param>
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public TriangulationPoint OppositePoint(DelaunayTriangle t, TriangulationPoint p) {
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Debug.Assert(t != this, "self-pointer error");
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return PointCWFrom(t.PointCWFrom(p));
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}
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public DelaunayTriangle NeighborCWFrom (TriangulationPoint point) { return Neighbors[(Points.IndexOf(point)+1)%3]; }
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public DelaunayTriangle NeighborCCWFrom (TriangulationPoint point) { return Neighbors[(Points.IndexOf(point)+2)%3]; }
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public DelaunayTriangle NeighborAcrossFrom(TriangulationPoint point) { return Neighbors[ Points.IndexOf(point) ]; }
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public TriangulationPoint PointCCWFrom(TriangulationPoint point) { return Points[(IndexOf(point)+1)%3]; }
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public TriangulationPoint PointCWFrom (TriangulationPoint point) { return Points[(IndexOf(point)+2)%3]; }
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private void RotateCW() {
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var t = Points[2];
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Points[2] = Points[1];
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Points[1] = Points[0];
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Points[0] = t;
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}
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/// <summary>
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/// Legalize triangle by rotating clockwise around oPoint
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/// </summary>
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/// <param name="oPoint">The origin point to rotate around</param>
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/// <param name="nPoint">???</param>
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public void Legalize(TriangulationPoint oPoint, TriangulationPoint nPoint) {
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RotateCW();
124-
Points[IndexCCWFrom(oPoint)] = nPoint;
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}
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public override string ToString() { return Points[0] + "," + Points[1] + "," + Points[2]; }
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/// <summary>
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/// Finalize edge marking
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/// </summary>
132-
public void MarkNeighborEdges() {
133-
for (int i = 0; i < 3; i++) if ( EdgeIsConstrained[i] && Neighbors[i] != null ) {
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Neighbors[i].MarkConstrainedEdge(Points[(i+1)%3], Points[(i+2)%3]);
135-
}
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}
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public void MarkEdge(DelaunayTriangle triangle) {
139-
for (int i = 0; i < 3; i++) if ( EdgeIsConstrained[i] ) {
140-
triangle.MarkConstrainedEdge(Points[(i+1)%3], Points[(i+2)%3]);
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}
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}
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public void MarkEdge(List<DelaunayTriangle> tList) {
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foreach ( DelaunayTriangle t in tList )
146-
for ( int i = 0; i < 3; i++ )
147-
if ( t.EdgeIsConstrained[i] )
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{
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MarkConstrainedEdge( t.Points[(i+1)%3], t.Points[(i+2)%3] );
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}
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}
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public void MarkConstrainedEdge(int index) {
154-
EdgeIsConstrained[index] = true;
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}
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public void MarkConstrainedEdge(DTSweepConstraint edge) {
158-
MarkConstrainedEdge(edge.P, edge.Q);
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}
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/// <summary>
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/// Mark edge as constrained
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/// </summary>
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public void MarkConstrainedEdge(TriangulationPoint p, TriangulationPoint q) {
165-
int i = EdgeIndex(p,q);
166-
if ( i != -1 ) EdgeIsConstrained[i] = true;
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}
168-
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public double Area() {
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double b = Points[0].X - Points[1].X;
171-
double h = Points[2].Y - Points[1].Y;
172-
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return Math.Abs((b * h * 0.5f));
174-
}
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public TriangulationPoint Centroid() {
177-
double cx = (Points[0].X + Points[1].X + Points[2].X) / 3f;
178-
double cy = (Points[0].Y + Points[1].Y + Points[2].Y) / 3f;
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return new TriangulationPoint(cx, cy);
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}
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/// <summary>
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/// Get the index of the neighbor that shares this edge (or -1 if it isn't shared)
184-
/// </summary>
185-
/// <returns>index of the shared edge or -1 if edge isn't shared</returns>
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public int EdgeIndex(TriangulationPoint p1, TriangulationPoint p2) {
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int i1 = Points.IndexOf(p1);
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int i2 = Points.IndexOf(p2);
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// Points of this triangle in the edge p1-p2
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bool a = (i1==0 || i2==0);
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bool b = (i1==1 || i2==1);
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bool c = (i1==2 || i2==2);
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if (b&&c) return 0;
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if (a&&c) return 1;
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if (a&&b) return 2;
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return -1;
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}
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201-
public bool GetConstrainedEdgeCCW ( TriangulationPoint p ) { return EdgeIsConstrained[(IndexOf(p)+2)%3]; }
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public bool GetConstrainedEdgeCW ( TriangulationPoint p ) { return EdgeIsConstrained[(IndexOf(p)+1)%3]; }
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public bool GetConstrainedEdgeAcross( TriangulationPoint p ) { return EdgeIsConstrained[ IndexOf(p) ]; }
204-
public void SetConstrainedEdgeCCW ( TriangulationPoint p, bool ce ) { EdgeIsConstrained[(IndexOf(p)+2)%3] = ce; }
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public void SetConstrainedEdgeCW ( TriangulationPoint p, bool ce ) { EdgeIsConstrained[(IndexOf(p)+1)%3] = ce; }
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public void SetConstrainedEdgeAcross( TriangulationPoint p, bool ce ) { EdgeIsConstrained[ IndexOf(p) ] = ce; }
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public bool GetDelaunayEdgeCCW ( TriangulationPoint p ) { return EdgeIsDelaunay[(IndexOf(p)+2)%3]; }
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public bool GetDelaunayEdgeCW ( TriangulationPoint p ) { return EdgeIsDelaunay[(IndexOf(p)+1)%3]; }
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public bool GetDelaunayEdgeAcross( TriangulationPoint p ) { return EdgeIsDelaunay[ IndexOf(p) ]; }
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public void SetDelaunayEdgeCCW ( TriangulationPoint p, bool ce ) { EdgeIsDelaunay[(IndexOf(p)+2)%3] = ce; }
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public void SetDelaunayEdgeCW ( TriangulationPoint p, bool ce ) { EdgeIsDelaunay[(IndexOf(p)+1)%3] = ce; }
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public void SetDelaunayEdgeAcross( TriangulationPoint p, bool ce ) { EdgeIsDelaunay[ IndexOf(p) ] = ce; }
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}
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}
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*/
31+
32+
/// Changes from the Java version
33+
/// attributification
34+
/// Future possibilities
35+
/// Flattening out the number of indirections
36+
/// Replacing arrays of 3 with fixed-length arrays?
37+
/// Replacing bool[3] with a bit array of some sort?
38+
/// Bundling everything into an AoS mess?
39+
/// Hardcode them all as ABC ?
40+
41+
using System;
42+
using System.Diagnostics;
43+
using System.Collections.Generic;
44+
45+
namespace Poly2Tri
46+
{
47+
public class DelaunayTriangle
48+
{
49+
public FixedArray3<TriangulationPoint> Points;
50+
public FixedArray3<DelaunayTriangle> Neighbors;
51+
public FixedBitArray3 EdgeIsConstrained, EdgeIsDelaunay;
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public bool IsInterior { get; set; }
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public DelaunayTriangle(TriangulationPoint p1, TriangulationPoint p2, TriangulationPoint p3)
54+
{
55+
Points[0] = p1;
56+
Points[1] = p2;
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Points[2] = p3;
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}
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public int IndexOf(TriangulationPoint p)
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{
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int i = Points.IndexOf(p);
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if (i == -1) throw new Exception("Calling index with a point that doesn't exist in triangle");
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return i;
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}
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public int IndexCWFrom(TriangulationPoint p) { return (IndexOf(p) + 2) % 3; }
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public int IndexCCWFrom(TriangulationPoint p) { return (IndexOf(p) + 1) % 3; }
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public bool Contains(TriangulationPoint p) { return Points.Contains(p); }
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/// <summary>
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/// Update neighbor pointers
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/// </summary>
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/// <param name="p1">Point 1 of the shared edge</param>
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/// <param name="p2">Point 2 of the shared edge</param>
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/// <param name="t">This triangle's new neighbor</param>
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private void MarkNeighbor(TriangulationPoint p1, TriangulationPoint p2, DelaunayTriangle t)
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{
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int i = EdgeIndex(p1, p2);
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if (i == -1) throw new Exception("Error marking neighbors -- t doesn't contain edge p1-p2!");
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Neighbors[i] = t;
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}
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/// <summary>
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/// Exhaustive search to update neighbor pointers
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/// </summary>
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public void MarkNeighbor(DelaunayTriangle t)
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{
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// Points of this triangle also belonging to t
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bool a = t.Contains(Points[0]);
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bool b = t.Contains(Points[1]);
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bool c = t.Contains(Points[2]);
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if (b && c) { Neighbors[0] = t; t.MarkNeighbor(Points[1], Points[2], this); }
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else if (a && c) { Neighbors[1] = t; t.MarkNeighbor(Points[0], Points[2], this); }
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else if (a && b) { Neighbors[2] = t; t.MarkNeighbor(Points[0], Points[1], this); }
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else throw new Exception("Failed to mark neighbor, doesn't share an edge!");
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}
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/// <param name="t">Opposite triangle</param>
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/// <param name="p">The point in t that isn't shared between the triangles</param>
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public TriangulationPoint OppositePoint(DelaunayTriangle t, TriangulationPoint p)
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{
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Debug.Assert(t != this, "self-pointer error");
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return PointCWFrom(t.PointCWFrom(p));
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}
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public DelaunayTriangle NeighborCWFrom(TriangulationPoint point) { return Neighbors[(Points.IndexOf(point) + 1) % 3]; }
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public DelaunayTriangle NeighborCCWFrom(TriangulationPoint point) { return Neighbors[(Points.IndexOf(point) + 2) % 3]; }
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public DelaunayTriangle NeighborAcrossFrom(TriangulationPoint point) { return Neighbors[Points.IndexOf(point)]; }
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public TriangulationPoint PointCCWFrom(TriangulationPoint point) { return Points[(IndexOf(point) + 1) % 3]; }
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public TriangulationPoint PointCWFrom(TriangulationPoint point) { return Points[(IndexOf(point) + 2) % 3]; }
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private void RotateCW()
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{
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var t = Points[2];
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Points[2] = Points[1];
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Points[1] = Points[0];
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Points[0] = t;
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}
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/// <summary>
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/// Legalize triangle by rotating clockwise around oPoint
125+
/// </summary>
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/// <param name="oPoint">The origin point to rotate around</param>
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/// <param name="nPoint">???</param>
128+
public void Legalize(TriangulationPoint oPoint, TriangulationPoint nPoint)
129+
{
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RotateCW();
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Points[IndexCCWFrom(oPoint)] = nPoint;
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}
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public override string ToString() { return Points[0] + "," + Points[1] + "," + Points[2]; }
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/// <summary>
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/// Finalize edge marking
138+
/// </summary>
139+
public void MarkNeighborEdges()
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{
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for (int i = 0; i < 3; i++) if (EdgeIsConstrained[i] && Neighbors[i] != null)
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{
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Neighbors[i].MarkConstrainedEdge(Points[(i + 1) % 3], Points[(i + 2) % 3]);
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}
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}
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public void MarkEdge(DelaunayTriangle triangle)
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{
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for (int i = 0; i < 3; i++) if (EdgeIsConstrained[i])
150+
{
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triangle.MarkConstrainedEdge(Points[(i + 1) % 3], Points[(i + 2) % 3]);
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}
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}
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public void MarkEdge(List<DelaunayTriangle> tList)
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{
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foreach (DelaunayTriangle t in tList)
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for (int i = 0; i < 3; i++)
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if (t.EdgeIsConstrained[i])
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{
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MarkConstrainedEdge(t.Points[(i + 1) % 3], t.Points[(i + 2) % 3]);
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}
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}
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public void MarkConstrainedEdge(int index)
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{
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EdgeIsConstrained[index] = true;
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}
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public void MarkConstrainedEdge(DTSweepConstraint edge)
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{
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MarkConstrainedEdge(edge.P, edge.Q);
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}
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/// <summary>
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/// Mark edge as constrained
177+
/// </summary>
178+
public void MarkConstrainedEdge(TriangulationPoint p, TriangulationPoint q)
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{
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int i = EdgeIndex(p, q);
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if (i != -1) EdgeIsConstrained[i] = true;
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}
183+
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public double Area()
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{
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double b = Points[0].X - Points[1].X;
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double h = Points[2].Y - Points[1].Y;
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return Math.Abs((b * h * 0.5f));
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}
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public TriangulationPoint Centroid()
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{
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double cx = (Points[0].X + Points[1].X + Points[2].X) / 3f;
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double cy = (Points[0].Y + Points[1].Y + Points[2].Y) / 3f;
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return new TriangulationPoint(cx, cy);
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}
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/// <summary>
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/// Get the index of the neighbor that shares this edge (or -1 if it isn't shared)
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/// </summary>
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/// <returns>index of the shared edge or -1 if edge isn't shared</returns>
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public int EdgeIndex(TriangulationPoint p1, TriangulationPoint p2)
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{
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int i1 = Points.IndexOf(p1);
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int i2 = Points.IndexOf(p2);
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// Points of this triangle in the edge p1-p2
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bool a = (i1 == 0 || i2 == 0);
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bool b = (i1 == 1 || i2 == 1);
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bool c = (i1 == 2 || i2 == 2);
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if (b && c) return 0;
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if (a && c) return 1;
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if (a && b) return 2;
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return -1;
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}
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public bool GetConstrainedEdgeCCW(TriangulationPoint p) { return EdgeIsConstrained[(IndexOf(p) + 2) % 3]; }
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public bool GetConstrainedEdgeCW(TriangulationPoint p) { return EdgeIsConstrained[(IndexOf(p) + 1) % 3]; }
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public bool GetConstrainedEdgeAcross(TriangulationPoint p) { return EdgeIsConstrained[IndexOf(p)]; }
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public void SetConstrainedEdgeCCW(TriangulationPoint p, bool ce) { EdgeIsConstrained[(IndexOf(p) + 2) % 3] = ce; }
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public void SetConstrainedEdgeCW(TriangulationPoint p, bool ce) { EdgeIsConstrained[(IndexOf(p) + 1) % 3] = ce; }
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public void SetConstrainedEdgeAcross(TriangulationPoint p, bool ce) { EdgeIsConstrained[IndexOf(p)] = ce; }
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public bool GetDelaunayEdgeCCW(TriangulationPoint p) { return EdgeIsDelaunay[(IndexOf(p) + 2) % 3]; }
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public bool GetDelaunayEdgeCW(TriangulationPoint p) { return EdgeIsDelaunay[(IndexOf(p) + 1) % 3]; }
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public bool GetDelaunayEdgeAcross(TriangulationPoint p) { return EdgeIsDelaunay[IndexOf(p)]; }
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public void SetDelaunayEdgeCCW(TriangulationPoint p, bool ce) { EdgeIsDelaunay[(IndexOf(p) + 2) % 3] = ce; }
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public void SetDelaunayEdgeCW(TriangulationPoint p, bool ce) { EdgeIsDelaunay[(IndexOf(p) + 1) % 3] = ce; }
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public void SetDelaunayEdgeAcross(TriangulationPoint p, bool ce) { EdgeIsDelaunay[IndexOf(p)] = ce; }
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}
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}

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