public static void EarInit(VertexStructure vertices)
{
VertexStructure v1 = vertices;
do {
VertexStructure v2 = v1.next;
VertexStructure v0 = v1.prev;
v1.ear = Diagonal (vertices, v0, v2);
v1 = v1.next;
} while (!ReferenceEquals (v1, vertices));
}
public static bool Diagonalie(VertexStructure vertices, VertexStructure a, VertexStructure b)
{
VertexStructure c = vertices;
do{
VertexStructure c1 = c.next;
if ( !ReferenceEquals(c,a) && !ReferenceEquals(c1,a)
&& !ReferenceEquals(c,b) && !ReferenceEquals(c1,b)
&& Intersect(a.v,b.v,c.v,c1.v) ) {
return false;
}
c = c.next;
}
while (!ReferenceEquals(c,vertices));
return true;
}
// Returns a list of points. Every sequence of three points make up a triangle.
public static List<Point> GetTriangulateTrianglePoints(VertexStructure vertices, int numVertices)
{
List<Point> pointList = new List<Point> ();
EarInit(vertices);
int n = numVertices;
while ( n > 3 ) {
VertexStructure v2 = vertices;
do {
if (v2.ear) {
VertexStructure v3 = v2.next;
VertexStructure v4 = v3.next;
VertexStructure v1 = v2.prev;
VertexStructure v0 = v1.prev;
// Save triangle v1,v2,v3
// Save diagonal v1,v3
pointList.Add(v1.v);
pointList.Add(v2.v);
pointList.Add(v3.v);
// Cut off ear v2
v1.next = v3;
v3.prev = v1;
vertices = v3;
// Update earity of v1 & v3
v1.ear = Diagonal (vertices, v0, v3);
v3.ear = Diagonal (vertices, v1, v4);
n--;
break;
}
v2 = v2.next;
} while (!ReferenceEquals (v2, vertices));
}
pointList.Add (vertices.v);
pointList.Add (vertices.next.v);
pointList.Add (vertices.next.next.v);
return pointList;
}
public static void DrawVertexStructure(VertexStructure vs, Context cr)
{
VertexStructure head = vs;
int i = 0;
do {
cr.MoveTo (vs.v);
cr.SetSourceRGB (0, 0, 0.8);
cr.Arc (vs.v.X, vs.v.Y, 2, 0, 2 * Math.PI);
cr.Fill ();
cr.LineWidth = 1;
cr.MoveTo (vs.v);
cr.LineTo(vs.next.v);
cr.Stroke();
vs = vs.next;
//Logger.Log("Meh..." + i);
i++;
} while(!ReferenceEquals(vs,head));
}
public static int Count(VertexStructure vertices)
{
int n = 0;
VertexStructure v = vertices;
do{
v = v.next;
n++;
}
while(!ReferenceEquals (v, vertices));
return n;
}
public static bool Diagonal(VertexStructure vertices, VertexStructure a, VertexStructure b)
{
return InCone(a,b) && InCone(b,a) && Diagonalie(vertices, a, b);
}
public static void Add(ref VertexStructure head, Point p)
{
VertexStructure vs = new VertexStructure (p);
VertexStructure.Add (ref head,vs);
}
public static void Add(ref VertexStructure head, VertexStructure v)
{
if (head != null) {
v.next = head;
v.prev = head.prev;
head.prev.next = v;
head.prev = v;
} else {
head = v;
head.prev = v;
head.prev = v;
}
}
public static void Triangulate(VertexStructure vertices, int numVertices)
{
EarInit(vertices);
int n = numVertices;
while ( n > 3 ) {
VertexStructure v2 = vertices;
do {
if (v2.ear) {
VertexStructure v3 = v2.next;
VertexStructure v4 = v3.next;
VertexStructure v1 = v2.prev;
VertexStructure v0 = v1.prev;
// Save triangle v1,v2,v3
// Save diagonal v1,v3
// Cut off ear v2
v1.next = v3;
v3.prev = v1;
vertices = v3;
// Update earity of v1 & v3
v1.ear = Diagonal (vertices, v0, v3);
v3.ear = Diagonal (vertices, v1, v4);
n--;
break;
}
v2 = v2.next;
} while (!ReferenceEquals (v2, vertices));
}
}
public static bool InCone(VertexStructure a, VertexStructure b)
{
VertexStructure a0 = a.prev;
VertexStructure a1 = a.next;
if (LeftOn (a.v, a1.v, a0.v)) {
return Left (a.v, b.v, a0.v)
&& Left (b.v, a.v, a1.v);
}
return !( LeftOn(a.v, b.v, a1.v)
&& LeftOn(b.v,a.v,a0.v) );
}
public void onKeyPress(object o, KeyPressEventArgs args)
{
Logger.Log ("key press " + args.Event.Key);
if (args.Event.Key == Gdk.Key.p && state != MyState.AddingPoints) {
state = MyState.AddingPoints;
return;
}
if (args.Event.Key == Gdk.Key.p && state == MyState.AddingPoints) {
foreach (PointD p in demo.points) {
VertexStructure.Add (ref vertices,p);
}
demo.points.Clear ();
demo.vertexStructs.Add (vertices);
state = MyState.NotAddingPoints;
vertices = null;
return;
}
if (args.Event.Key == Gdk.Key.t) {
foreach (VertexStructure polygon in demo.vertexStructs) {
List<PointD> pointList = Geometry.ComputationalGeometry.GetTriangulateTrianglePoints (polygon,VertexStructure.Count(polygon));
List<PointD>.Enumerator iter = pointList.GetEnumerator();
iter.MoveNext ();
do {
PointD a = iter.Current;
iter.MoveNext ();
PointD b = iter.Current;
iter.MoveNext ();
PointD c = iter.Current;
Triangle t = new Triangle (a, b, c);
ActiveTriangle nt = new ActiveTriangle (demo,t);
demo.addObject(nt);
} while(iter.MoveNext ());
Logger.Log ("Iterated");
}
demo.vertexStructs.Clear ();
return;
}
if (args.Event.Key == Gdk.Key.e || args.Event.Key == Gdk.Key.n) {
List<IGameObject> goList = demo.getObjectsByTag (ActiveTriangle.tag);
foreach (IGameObject go in goList){
ActiveTriangle t = (ActiveTriangle) go;
switch (args.Event.Key) {
case Gdk.Key.e:
t.setEvil ();
break;
case Gdk.Key.n:
t.setNeutral ();
break;
default:
t.setNeutral ();
break;
}
}
}
if (args.Event.Key == Gdk.Key.o) {
demo.addObject (new Protagonist (demo));
}
}