Modify a text file: $/players4331a.java

$/players4331a.java

//// Exercise 4331a:  Defining and using objects - part 1.

String title=  "Exercise 4331a:  Defining and using objects";

int left=20, right=  left+600;        // Boundaries of a rectangular field.
int top=50, bottom=  top+400;         // (Leave room for text).

Player george;          //// Declare an  object. ////

void setup() {
  //// Set up the screen and reset everything else.
  size( right+20, bottom+30 );
  reset();    // New players.
}
void reset() {
  //// Create new object ////
  george=  new Player();
  george.name=  "George";
}

void draw() {
  //// Next frame:  move the players, then draw them.
  background( 200, 200, 255 );    // Sky blue;
  scene();
  george.move();
  george.show();
}
void scene() {
  //// Draw a light-brown field, plus some grass at the bottom.
  fill( 200, 150, 100 );
  noStroke();
  rectMode(CORNERS);
  rect( left, top, right, bottom );      // Field.
  text( title, width/4, 25 );
}

class Player {
  //////// Player HAS: has position, velocity, etc. and drawing characteristics.
  //// Player DOES:  move(), show()
 
  float x=100,y=100;    // Position on the screen (i.e. "coordinates")
  float dx=3,dy=2;  // How far to move in one flame (i.e. "velocity")
 
  String name="Whatever";      // Name of this player 
  int r1=100, g1=150, b1=50;   // Color of this player (body);
  int w=30,h=50;    // Width and height of this player's body (with default values).
  
  //// METHODS ////
  void move() {
    //// Move this player. ////
    if (x<left+w/2 || x>right-w/2) dx=  -dx;     // Bounce off boundaries.
    if (y<top+h/2 || y>bottom-h/2) dy=  -dy; 
    x += dx;
    y += dy;
  }
  void show() {
    //// Display this player on the screen (at x,y, with color rgb, etc.)
    rectMode( CENTER );
    fill( r1,g1,b1 );
    rect( x,y, w,h );                  // Body.
    ellipseMode( CENTER );
    ellipse( x, y-h/2-12, 24, 24 );    // Head.
    fill(0);
    text( name, x-w/2+3, y-10 );
  }
      
}// END OF class Player. //