// July 2002, java applet by Oliver Knill  for the CCP project
// Green's Theorem and the Planimeter by Oliver Knill and Dale Winter
// Harvard University, Nov 15, 2002. See
// http://math.duke.edu/education/ccp/materials/mvcalc/green
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License of the Free Software Foundation for
// details. 

import java.lang.Math;
import java.awt.*;

class curve {

public  int h,w;                  // width and height taken over 
private int cx1, cy1;             // previous plot point
private int cx2, cy2;             // next plot point
private int interpolation=400;    // number of interpolation points
private int re,gr,bl;             // red, green, blue
private int re0,gr0,bl0;          // red, green, blue
private int i;                    // index
private double twopi=6.283185307; // constant 2*pi

public curve(int width,int height) {
  this.w = width;   this.h = height;
}

public void draw_dot(Graphics g,
                     int red, int green, int blue,
                     int center_x,int center_y,int dot_size) {
  g.setColor(new Color(red,green,blue));
  g.drawOval(center_x-dot_size,center_y-dot_size,2*dot_size,2*dot_size);
}

public void draw_text(Graphics g, int red, int green, int blue,
                         int center_x,int center_y,
                         int size,String text) {
  g.setColor(new Color(red,green,blue));
  Font f = new Font("Helvetica",Font.BOLD,size); g.setFont(f);
  g.drawString(text,center_x+10,center_y);
}

public void draw_poteto(Graphics g,
                         int red, int green, int blue,
                         int center_x,int center_y,
                         int scale_x,int scale_y,String text,
                         int dot_size) {
  g.setColor(new Color(red,green,blue));
  for (i=0; i<interpolation+1; i++) {
    cx1=(int) (center_x+scale_x*Math.cos(twopi*i/interpolation));
    cy1=(int) (center_y+scale_y*Math.sin(twopi*i/interpolation)
                       +scale_y*Math.sin(2*twopi*i/interpolation)/2);
    cx2=(int) (center_x+scale_x*Math.cos(twopi*(i+1)/interpolation));
    cy2=(int) (center_y+scale_y*Math.sin(twopi*(i+1)/interpolation)
                       +scale_y*Math.sin(2*twopi*(i+1)/interpolation)/2);
    g.drawLine(cx1,cy1,cx2,cy2);
  }
  draw_text(g,red,green,blue,center_x+scale_x,center_y,12,text);
  draw_dot(g,red,green,blue,center_x+scale_x,center_y,dot_size);
}

public void draw_flower(Graphics g,
                         int red, int green, int blue,
                         int center_x,int center_y,
                         int scale_x,int scale_y,String text,
                         int dot_size) {
  g.setColor(new Color(red,green,blue));
  for (i=0; i<interpolation+1; i++) {
    cx1=(int) (center_x+scale_x*Math.cos(twopi*i/interpolation));
    cy1=(int) (center_y+scale_y*Math.sin(twopi*i/interpolation)
                       +scale_y*Math.sin(3*twopi*i/interpolation)/2);
    cx2=(int) (center_x+scale_x*Math.cos(twopi*(i+1)/interpolation));
    cy2=(int) (center_y+scale_y*Math.sin(twopi*(i+1)/interpolation)
                       +scale_y*Math.sin(3*twopi*(i+1)/interpolation)/2);
    g.drawLine(cx1,cy1,cx2,cy2);
  }
  draw_text(g,red,green,blue,center_x+scale_x,center_y,12,text);
  draw_dot(g,red,green,blue,center_x+scale_x,center_y,dot_size);
}


public void draw_ellipse(Graphics g,
                         int red, int green, int blue,
                         int center_x,int center_y,
                         int scale_x,int scale_y,String text,
                         int dot_size) {
  g.setColor(new Color(red,green,blue));
  for (i=0; i<interpolation+1; i++) {
    cx1=(int) (center_x+scale_x*Math.cos(twopi*i/interpolation));
    cy1=(int) (center_y+scale_y*Math.sin(twopi*i/interpolation));
    cx2=(int) (center_x+scale_x*Math.cos(twopi*(i+1)/interpolation));
    cy2=(int) (center_y+scale_y*Math.sin(twopi*(i+1)/interpolation));
    g.drawLine(cx1,cy1,cx2,cy2);
  }
  draw_text(g,red,green,blue,center_x+scale_x,center_y,12,text);
  draw_dot(g,red,green,blue,center_x+scale_x,center_y,dot_size);
}

public void draw_rectangle(Graphics g,
                         int red, int green, int blue,
                         int center_x,int center_y,
                         int scale_x,int scale_y,String text,
                         int dot_size) {
  g.setColor(new Color(red,green,blue));
  g.drawLine(center_x-scale_x,center_y-scale_y,center_x+scale_x,center_y-scale_y);
  g.drawLine(center_x+scale_x,center_y-scale_y,center_x+scale_x,center_y+scale_y);
  g.drawLine(center_x+scale_x,center_y+scale_y,center_x-scale_x,center_y+scale_y);
  g.drawLine(center_x-scale_x,center_y+scale_y,center_x-scale_x,center_y-scale_y);
  draw_text(g,red,green,blue,center_x+scale_x,center_y,12,text);
  draw_dot (g,red,green,blue,center_x+scale_x,center_y,dot_size);
}

public void draw_triangle(Graphics g,
                         int red, int green, int blue,
                         int center_x,int center_y,
                         int scale_x,int scale_y,String text,
                         int dot_size) {
  g.setColor(new Color(red,green,blue));
  g.drawLine(center_x-scale_x,center_y-scale_y,center_x+scale_x,center_y-scale_y);
  g.drawLine(center_x+scale_x,center_y-scale_y,center_x,center_y+scale_y);
  g.drawLine(center_x,center_y+scale_y,center_x-scale_x,center_y-scale_y);
  draw_text(g,red,green,blue,center_x+scale_x,center_y-scale_y,12,text);
  draw_dot(g,red,green,blue,center_x+scale_x,center_y-scale_y,dot_size);
}

public void erase(Graphics g) {
   draw_ellipse(g,0,0,0,350,200,80,100,"Start",2); 
   draw_ellipse(g,0,0,0,350,200,80, 80,"Start",2); 
   draw_poteto(g,0,0,0,350,200,80,100,"Start",2); 
   draw_rectangle(g,0,0,0,350,200,80,80,"Start",2); 
   draw_triangle(g,0,0,0,350,280,80,80,"Start",2);  
   draw_flower(g,0,0,0,350,200,80,100,"Start",2);
}

public void menu(Graphics g,boolean over,int curve) {
   re0=0; gr0=255; bl0=0; 
   if (over) { re=255; gr=255; bl=0; } else { re=255; gr=255; bl=0; }
   
   g.setColor(new Color(75,0,75));               // menu rectangle around wheel
   g.drawRect(0,0,50,75);

   g.setColor(new Color(0,75,0));                // menu rectangle around curves
   g.drawRect(0,80,50,350);

   g.setColor(new Color(0,255,0));
   draw_text(g,re0,gr0,bl0,1,100,12,"Menu"); 
   switch (curve) {
     case 1: 
             draw_ellipse(g,re,gr,bl,25,150,2*8,2*10,"",0);
             draw_ellipse(g,re0,gr0,bl0,25,200,2*8, 2*8,"",0);
             draw_poteto(g,re0,gr0,bl0,25,250,2*8,2*10,"",0);
             draw_rectangle(g,re0,gr0,bl0,25,300,2*8,2*8,"",0); 
             draw_triangle(g,re0,gr0,bl0,25,350,2*8,2*8,"",0);
             draw_flower(g,re0,gr0,bl0,25,400,2*8,2*10,"",0);
             break; 
     case 2: 
             draw_ellipse(g,re0,gr0,bl0,25,150,2*8,2*10,"",0);
             draw_ellipse(g,re,gr,bl,25,200,2*8, 2*8,"",0);
             draw_poteto(g,re0,gr0,bl0,25,250,2*8,2*10,"",0);
             draw_rectangle(g,re0,gr0,bl0,25,300,2*8,2*8,"",0); 
             draw_triangle(g,re0,gr0,bl0,25,350,2*8,2*8,"",0);
             draw_flower(g,re0,gr0,bl0,25,400,2*8,2*10,"",0);
             break; 
     case 3: 
             draw_ellipse(g,re0,gr0,bl0,25,150,2*8,2*10,"",0);
             draw_ellipse(g,re0,gr0,bl0,25,200,2*8, 2*8,"",0);
             draw_poteto(g,re,gr,bl,25,250,2*8,2*10,"",0);
             draw_rectangle(g,re0,gr0,bl0,25,300,2*8,2*8,"",0); 
             draw_triangle(g,re0,gr0,bl0,25,350,2*8,2*8,"",0);
             draw_flower(g,re0,gr0,bl0,25,400,2*8,2*10,"",0);
             break; 
     case 4: 
             draw_ellipse(g,re0,gr0,bl0,25,150,2*8,2*10,"",0);
             draw_ellipse(g,re0,gr0,bl0,25,200,2*8, 2*8,"",0);
             draw_poteto(g,re0,gr0,bl0,25,250,2*8,2*10,"",0);
             draw_rectangle(g,re,gr,bl,25,300,2*8,2*8,"",0); 
             draw_triangle(g,re0,gr0,bl0,25,350,2*8,2*8,"",0);
             draw_flower(g,re0,gr0,bl0,25,400,2*8,2*10,"",0);
             break;
     case 5:
             draw_ellipse(g,re0,gr0,bl0,25,150,2*8,2*10,"",0);
             draw_ellipse(g,re0,gr0,bl0,25,200,2*8, 2*8,"",0);
             draw_poteto(g,re0,gr0,bl0,25,250,2*8,2*10,"",0);
             draw_rectangle(g,re0,gr0,bl0,25,300,2*8,2*8,"",0);
             draw_triangle(g,re,gr,bl,25,350,2*8,2*8,"",0);
             draw_flower(g,re0,gr0,bl0,25,400,2*8,2*10,"",0);
             break;
     case 6:
             draw_ellipse(g,re0,gr0,bl0,25,150,2*8,2*10,"",0);
             draw_ellipse(g,re0,gr0,bl0,25,200,2*8, 2*8,"",0);
             draw_poteto(g,re0,gr0,bl0,25,250,2*8,2*10,"",0);
             draw_rectangle(g,re0,gr0,bl0,25,300,2*8,2*8,"",0);
             draw_triangle(g,re0,gr0,bl0,25,350,2*8,2*8,"",0);
             draw_flower(g,re,gr,bl,25,400,2*8,2*10,"",0);
             break;
     default: 
             draw_ellipse(g,re0,gr0,bl0,25,150,2*8,2*10,"",0);
             draw_ellipse(g,re0,gr0,bl0,25,200,2*8, 2*8,"",0);
             draw_poteto(g,re0,gr0,bl0,25,250,2*8,2*10,"",0);
             draw_rectangle(g,re0,gr0,bl0,25,300,2*8,2*8,"",0); 
             draw_triangle(g,re0,gr0,bl0,25,350,2*8,2*8,"",0);
             draw_flower(g,re0,gr0,bl0,25,400,2*8,2*10,"",0);
             break;
   }
}

public void update(Graphics g,boolean status, int c) {
  switch(c) {
    case 1: draw_ellipse(g,0,255,0,350,200,80,100,"Start",2); break;
    case 2: draw_ellipse(g,0,255,0,350,200,80,80,"Start",2);  break;
    case 3: draw_poteto(g,0,255,0,350,200,80,100,"Start",2); break;
    case 4: draw_rectangle(g,0,255,0,350,200,80,80,"Start",2); break;
    case 5: draw_triangle(g,0,255,0,350,280,80,80,"Start",2); break;
    case 6: draw_flower(g,0,255,0,350,200,80,100,"Start",2); break;
    default: break; 
  }
}

}