import java.awt.*;

public class catmullpatch extends BufferedApplet
{
   int w = 0, h = 0;
   int selected=1;
   int aa,bb,cc;
   Cubic spline;
   Cubic spline2;
   Cubic spline3;
   double GX[][] = {{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0}};
   double GX2[][]={{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0}};
   double GX3[][]={{0,0,0,0},{0,0,0,0},{0,0,0,0},{0,0,0,0}};
   double min;
   double tension=0.5;
   double distance=0;
   double time=1;
   boolean bounceflag;
   double snapped[][]=new double[4][4];
   public void init(){
         w = bounds().width;
         h = bounds().height;      
    }
    
   public void render(Graphics g) {
       time+=1;
       for (int a=0;a<4;a++){
          for (int b=0;b<4;b++){
              if (snapped[a][b]!=0){
                  GX[a][b]+=(10/(time-snapped[a][b]))*10*Math.sin(time-snapped[a][b]);
                  if (time-snapped[a][b]>50){
                      snapped[a][b]=0;
                    }
                }
            }
       }
       
       spline=new Cubic(GX,tension);
       
      for (int a=0;a<4;a++){
          for (int b=0;b<3;b++){
              GX2[a][b]=GX[a][b+1];
            }
        } 
      spline2=new Cubic(GX2,tension);
      
      for (int a=0;a<4;a++){
          for (int b=1;b<4;b++){
              GX3[a][b]=GX[a][b-1];
            }
        }
        
         spline3=new Cubic(GX3,tension);
      g.setColor(Color.white);
      g.fillRect(0,0,w,h);
      g.setColor(Color.blue);
        
        g.drawLine(150,150,150,250);
        g.drawLine(150,150,250,150);
        g.drawLine(250,150,250,250);
        g.drawLine(150,250,250,250);
        
        g.drawLine(200,200,200,300);
        g.drawLine(200,200,300,200);
        g.drawLine(300,200,300,300);
        g.drawLine(200,300,300,300);
        
        g.drawLine(150,150,200,200);
        g.drawLine(250,150,300,200);
        g.drawLine(150,250,200,300);
        g.drawLine(250,250,300,300);
      
      g.setColor(Color.black);
      for (double u = 0 ; u < 1 ; u+=.1) {
      for (double v = 0 ; v < 1 ; v+=.03) {
        int y = (int)(spline.eval(u,v));
        int y2 = (int)(spline.eval(u,v+.01));
        g.drawLine((int)(v*100+u*50)+150,(int)(y+u*50)+150,(int)(v*100+1+u*50)+150,(int)(y2+u*50)+150);
    }
    }
     for (double u = 0 ; u < 1 ; u+=.03) {
      for (double v = 0 ; v < 1 ; v+=.1) {
        int y = (int)(spline.eval(u,v));
        int y2 = (int)(spline.eval(u+.01,v));
        g.drawLine((int)(v*100+u*50)+150,(int)(y+u*50)+150,(int)(v*100+1+u*50)+150,(int)(y2+u*50)+150);
    }    
    }
    
    for (double u = 0 ; u < 1 ; u+=.1) {
      for (double v = 0 ; v < 1 ; v+=.03) {
        int y = (int)(spline2.eval(u,v));
        int y2 = (int)(spline2.eval(u,v+.01));
        g.drawLine((int)(v*100+u*50)+250,(int)(y+u*50)+150,(int)(v*100+1+u*50)+250,(int)(y2+u*50)+150);
    }
    }
     for (double u = 0 ; u < 1 ; u+=.03) {
      for (double v = 0 ; v < 1 ; v+=.1) {
        int y = (int)(spline2.eval(u,v));
        int y2 = (int)(spline2.eval(u+.01,v));
        g.drawLine((int)(v*100+u*50)+250,(int)(y+u*50)+150,(int)(v*100+1+u*50)+250,(int)(y2+u*50)+150);
    }    
    }
    for (double u = 0 ; u < 1 ; u+=.1) {
      for (double v = 0 ; v < 1 ; v+=.03) {
        int y = (int)(spline3.eval(u,v));
        int y2 = (int)(spline3.eval(u,v+.01));
        g.drawLine((int)(v*100+u*50)+50,(int)(y+u*50)+150,(int)(v*100+1+u*50)+50,(int)(y2+u*50)+150);
    }
    }
     for (double u = 0 ; u < 1 ; u+=.03) {
      for (double v = 0 ; v < 1 ; v+=.1) {
        int y = (int)(spline3.eval(u,v));
        int y2 = (int)(spline3.eval(u+.01,v));
        g.drawLine((int)(v*100+u*50)+50,(int)(y+u*50)+150,(int)(v*100+1+u*50)+50,(int)(y2+u*50)+150);
    }    
    }
    g.setColor(Color.red);
    for(int a=0;a<4;a++){
        for (int b=0;b<4;b++){
            g.drawOval(a*100+b*50 -5,b*50+(int)GX[b][a] +100-5,10,10);
        }
    }
   }

    public boolean keyUp(Event e, int key) {
        switch (key)
        {
            case '1':
            aa=0;
            bb=0;
            cc=1;
            break;
            case '2':
            aa=0;
            bb=1;
            cc=1;
            break;
            case '3':
            aa=0;
            bb=2;
            cc=1;
            break;
            case '4':
            aa=0;
            bb=3;
            cc=1;
            break;
            case 'q':
            aa=1;
            bb=0;
            cc=1;
            break;
            case 'w':
            aa=1;
            bb=1;
            cc=1;
            break;
            case 'e':
            aa=1;
            bb=2;
            cc=1;
            break;
            case 'r':
            aa=1;
            bb=3;
            cc=1;
            break;
            case 'a':
            aa=2;
            bb=0;
            cc=1;
            break;
            case 's':
            aa=2;
            bb=1;
            cc=1;
            break;
            case 'd':
            aa=2;
            bb=2;
            cc=1;
            break;
            case 'f':
            aa=2;
            bb=3;
            cc=1;
            break;
            case 'z':
            aa=3;
            bb=0;
            cc=1;
            break;
            case 'x':
            aa=3;
            bb=1;
            cc=1;
            break;
            case 'c':
            aa=3;
            bb=2;
            cc=1;
            break;
            case 'v':
            aa=3;
            bb=3;
            cc=1;
            break;
            case '!':
            aa=0;
            bb=0;
            cc=-1;
            break;
            case '@':
            aa=0;
            bb=1;
            cc=-1;
            break;
            case '#':
            aa=0;
            bb=2;
            cc=-1;
            break;
            case '$':
            aa=0;
            bb=3;
            cc=-1;
            break;
            case 'Q':
            aa=1;
            bb=0;
            cc=-1;
            break;
            case 'W':
            aa=1;
            bb=1;
            cc=-1;
            break;
            case 'E':
            aa=1;
            bb=2;
            cc=-1;
            break;
            case 'R':
            aa=1;
            bb=3;
            cc=-1;
            break;
            case 'A':
            aa=2;
            bb=0;
            cc=-1;
            break;
            case 'S':
            aa=2;
            bb=1;
            cc=-1;
            break;
            case 'D':
            aa=2;
            bb=2;
            cc=-1;
            break;
            case 'F':
            aa=2;
            bb=3;
            cc=-1;
            break;
            case 'Z':
            aa=3;
            bb=0;
            cc=-1;
            break;
            case 'X':
            aa=3;
            bb=1;
            cc=-1;
            break;
            case 'C':
            aa=3;
            bb=2;
            cc=-1;
            break;
            case 'V':
            aa=3;
            bb=3;
            cc=-1;
            break;
            case '[':
            tension-=.25;
            cc=-2;
            break;
            case ']':
            tension+=.25;
            cc=-2;
            break;
            
        }
        if (cc!=-2 && snapped[aa][bb]==0){
            GX[aa][bb]+=20*cc;
            GX[aa][bb]-=110;
            snapped[aa][bb]=time;
        }
        damage=true;
        return true;
    }
   public boolean mouseUp(Event e, int x, int y) {
return true;
   }

   public boolean mouseDrag(Event e, int x, int y) {
     damage=true;
      return true;
   }
}