Modify a text file: $/2914a-colors.java

$/2914a-colors.java

//// Exercise in class -- color-changing square.

float x,y, w,h;    // Position and size of square.
int r,g,b;        // Color of fill.
int kr=255,kg=255,kb=255;        // Color of fill.
int birdX=50, birdY=50, birdDX=10, birdDY=10, birdW=30;

void setup() {
  size( 800, 600 );
  //// Initialize the position, color, etc.
  x=  width/2;  y=  height/2;
  w=  width/4;  h=  height/4;
  rectMode(CENTER);
  ellipseMode(CENTER);
  //// Initialize colors.
  fillColor();  
  bgColor();
}

void draw() {
  background( kr, kg, kb );
  fill( (128+kr)%256, (128+kg)%256, (128+kb)%256 );
  text( "Click within rectangle, to change color!", 10, 10 );
  text( "Press 'k' to change background color!", 10, 25 );
  //// Chase mouse & squeeze the creature.
  chase();
  squeeze();
  creature();
  //// Birds
  bird();
  //// Debugging:    Display some values on screen.
  fill( 0 );
  text( "w= "+w, width-100, height-20 );
  text( "h= "+h, width-100, height-10 );
}
void creature() {
  //// Draw creature at x,y
  //// FIll with latest color.
  fill( r,g,b );
  rect( x,y, w,h );
  //// Complimentary color for head.
  float d=  (h+w) / 6;      // Diameter of head.
  fill( (128+r)%256, (128+g)%256, (128+b)%256 );
  ellipse( x, y-h/2-d/2, d, d );
}
void bird() {
  //// Draw bird.
  birdDX=  (birdX>0 && birdX<width) ? birdDX : -birdDX;
  birdX += birdDX;
  birdDY=  (birdY>0 && birdY<height) ? birdDY : -birdDY;
  birdY += birdDY;
  //// Fill with latest color.
  fill( r,g,b );
  triangle( birdX+birdW,birdY, birdX-50+birdW,birdY-15, birdX-50+birdW,birdY+15); 
  text( birdDX, width-50,50 );
}

void keyPressed() {
  //// 'k' changes bg color randomly.
  if (key == 'k') {
    bgColor();
  }
}
void bgColor() {
  //// Change bg color randomly.
  kr=  int( random(255) );
  kg=  int( random(255) );
  kb=  int( random(255) );
}
void mousePressed() {
  //// Change fill color randomly, when click is within rectangle.
  if ( abs(mouseX-x)<w/2 && abs(mouseY-y)<h/2  ) {
    fillColor();
  }
}
void fillColor() {
  //// Change fill color randomly.
    r=  int( random(255) );
    g=  int( random(255) );
    b=  int( random(255) );
}

void chase() {
  //// Chase the mouse:  
  //    cut x distance in half, y by 1/3.
  float dx=  mouseX - x;
  float dy=  mouseY - y;
  x = x + dx/30;
  y = y + dy/20;
}  
void squeeze() {
  //// Squeeze the mouse:  
  //    Shrink from L to R, bottom to top.
  w=  10 + 100 * ( x/width );
  h=  20 + 200 * ( y/height );
}