added face detection

drawing/Edge.pde

@@ -1,5 +1,6 @@
 class Edge extends Gui_element{
   Vertex v1,v2;
+  boolean searched=false;
   Edge(Vertex _v1, Vertex _v2){
     v1=_v1;v2=_v2;
     v1.E.add(this);

drawing/drawing.pde

@@ -5,6 +5,9 @@ final int DRAW_NORMAL=1;
 final int DRAW_DRAG=2;
 final int DRAW_ANIMATION=3;
 final int Vertex_Rad=8;
+final int Width=600;
+final int Height=600;
+final int Margin=10;
 ArrayList<Gui_element> gui=new ArrayList();
 Gui_element gui_current=null;
 Vertex drag_start;
@@ -16,7 +19,7 @@ final int animation_duration=1000;
 void setup() {
   size(600, 600);
   background(255);
-  draw_button.disable=true;
+  draw_button.disable=false;
   gui.add(draw_button);
   gui.add(new Button(500, 500, 80, 40, color(150), "Initial Graph", new InitialGraphEvent()));
   gui.add(new Button(500, 550, 80, 40, color(150), "Reset", new ResetEvent()));
@@ -72,7 +75,7 @@ void mousePressed() {
     Vertex v=new Vertex(mouseX, mouseY);
     G.V.add(v);
     gui.add(v);
-    draw_button.disable=!G.ValidGraph();
+    //draw_button.disable=!G.ValidGraph();
   } else {
     gui_current.mousePressed();
   }
@@ -86,7 +89,7 @@ void mouseReleased() {
         Edge e=new Edge(drag_start, (Vertex)gui_current);
         G.E.add(e);
         gui.add(e);
-        draw_button.disable=!G.ValidGraph();
+        //draw_button.disable=!G.ValidGraph();
         println("Valid");
       } else {
         println("Invalid");
@@ -111,7 +114,7 @@ class InitialGraphEvent implements ButtonEvent {
           gui.add(e);
         }
       }while (G.check3edges_per_vertex (G.V.get (i)));
-      draw_button.disable=!G.ValidGraph();
+      //draw_button.disable=!G.ValidGraph();
     }
   }
 }
@@ -128,6 +131,22 @@ class TutteDrawEvent implements ButtonEvent {
   void onclick() {
     int l=G.V.size();
 
+    ArrayList<Vertex> face=FindFace();
+    print("0");
+    for(Vertex v:face){
+      print(" -",G.V.indexOf(v));
+    }
+    println();
+    int a=0;
+    for(Vertex v:face){
+      ++a;
+      int b=G.V.indexOf(v);
+      if(a!=b){
+        Vertex t=G.V.get(a);
+        G.V.set(a,G.V.get(b));
+        G.V.set(b,t);
+      }
+    }
     //Matrix L
     float[][] L=new float[l][l];
     for(int i=0;i<l;++i){
@@ -142,50 +161,96 @@ class TutteDrawEvent implements ButtonEvent {
             }
           }
         }
-        //print(" ",L[i][j]);
       }
-      //println();
     }
-
-    float[][] L1=new float[3][3];
-    float[][] L2=new float[l-3][l-3];
-    float[][] B=new float[l-3][3];
-    for(int i=0;i<3;++i){
-      for(int j=0;j<3;++j){
+    int n=face.size()+1;
+    float[][] L1=new float[n][n];
+    float[][] L2=new float[l-n][l-n];
+    float[][] B=new float[l-n][n];
+    for(int i=0;i<n;++i){
+      for(int j=0;j<n;++j){
         L1[i][j]=L[i][j];
       }
     }
-    for(int i=0;i<l-3;++i){
-      for(int j=0;j<l-3;++j){
-        L2[i][j]=L[i+3][j+3];
+    for(int i=0;i<l-n;++i){
+      for(int j=0;j<l-n;++j){
+        L2[i][j]=L[i+n][j+n];
       }
     }
-    for(int i=0;i<l-3;++i){
-      for(int j=0;j<3;++j){
-        B[i][j]=L[i+3][j];
+    for(int i=0;i<l-n;++i){
+      for(int j=0;j<n;++j){
+        B[i][j]=L[i+n][j];
       }
     }
 
-    float[][] P1=new float[][]{{10,10},{590,10},{300,590}};
+    float[][] P1=new float[n][2];
+    for(int i=0;i<n;++i){
+      P1[i][0]=sin(i*PI*2/n)*(Height/2-Margin)+Width/2;
+      P1[i][1]=Height/2-cos(i*PI*2/n)*(Height/2-Margin);
+      println(P1[i][0], " " ,P1[i][1]);
+    }
+    Mat.print(L2,2);
     float[][] invL2= Mat.inverse(L2);
     float[][] nagP2=Mat.multiply(Mat.multiply(invL2,B),P1);
     orig=new float[l][2];
     targ=new float[l][2];
-    for(int i=0;i<3;++i){
+    for(int i=0;i<n;++i){
       orig[i][0]=G.V.get(i).x;
       orig[i][1]=G.V.get(i).y;
       targ[i][0]=(int)P1[i][0];
       targ[i][1]=(int)P1[i][1];
     }
-    for(int i=3;i<l;++i){
+    for(int i=n;i<l;++i){
       orig[i][0]=G.V.get(i).x;
       orig[i][1]=G.V.get(i).y;
-      targ[i][0]=(int)-nagP2[i-3][0];
-      targ[i][1]=(int)-nagP2[i-3][1];
+      targ[i][0]=(int)-nagP2[i-n][0];
+      targ[i][1]=(int)-nagP2[i-n][1];
     }
     animation_start_time=millis();
     draw_state=DRAW_ANIMATION;
   }
+  ArrayList<Vertex> FindFaceDFSID(Vertex vs,Vertex vc,int n){//Vsource, Vcurrent, depth
+    if(n==1){//edge of the search
+      for(Edge e:vc.E){
+        if(!e.searched){
+          if((e.v1==vc&&e.v2==vs)||(e.v1==vs&&e.v2==vc)){//find loop
+            println("found!");
+            return new ArrayList();
+          }
+        }  
+      }
+      return null;
+    }else{
+      for(Edge e:vc.E){
+        if(!e.searched){
+          e.searched=true;
+          Vertex nvc;
+          if(e.v1==vc){
+            nvc=e.v2;
+          }else{
+            nvc=e.v1;
+          }
+          ArrayList<Vertex> rt=FindFaceDFSID(vs,nvc,n-1);
+          if(rt!=null){
+            rt.add(nvc);
+            return rt;
+          }
+          e.searched=false;
+        }  
+      }
+    }
+    return null;
+  }
+  ArrayList<Vertex> FindFace(){
+    for(Edge e:G.E){
+      e.searched=false;
+    }
+    for(int i=3;i<=G.E.size();++i){
+      ArrayList rt=FindFaceDFSID(G.V.get(0), G.V.get(0), i);
+      if(rt!=null)return rt;
+    }
+    return null;
+  }
 }