/* built with Studio Sketchpad: 
 *   https://sketchpad.cc
 * 
 * observe the evolution of this sketch: 
 *   https://studio.sketchpad.cc/sp/pad/view/ro.9G-Hu-KK84R/rev.257
 * 
 * authors: 
 *   Nathaniel Phillips
 *   Kevin Crouch

 * license (unless otherwise specified): 
 *   creative commons attribution-share alike 3.0 license.
 *   https://creativecommons.org/licenses/by-sa/3.0/ 
 */ 



// Global variables for the ball  
float ball_x;  
float ball_y;  
float ball_dir = 1;  
float ball_size = 5;  // Radius  
float dy = 0;  // Direction  
  
// Global variables for the paddle  
int paddle_width = 5;  
int paddle_height = 20;  
  
int dist_wall = 15;  
  
void setup()  
{  
  size(200, 200);  
  rectMode(CENTER_RADIUS);  
  ellipseMode(CENTER_RADIUS);  
  noStroke();  
  smooth();  
  ball_y = height/2;  
  ball_x = 1;  
}  
  
void draw()   
{  
  background(255);  
    
  ball_x += ball_dir * 1.0;  
  ball_y += dy;  
  if(ball_x > width+ball_size) {  
    ball_x = -width/2 - ball_size;  
    ball_y = random(0, height);  
    dy = 0;  
  }  
    
  // Constrain paddle to screen  
  float paddle_y = constrain(mouseY, paddle_height, height-paddle_height);  
  
  // Test to see if the ball is touching the paddle  
  float py = width-dist_wall-paddle_width-ball_size;  
  if(ball_x == py   
     && ball_y > paddle_y - paddle_height - ball_size   
     && ball_y < paddle_y + paddle_height + ball_size) {  
    ball_dir *= -1;  
    if(mouseY != pmouseY) {  
      dy = (mouseY-pmouseY)/2.0;  
      if(dy >  5) { dy =  5; }  
      if(dy < -5) { dy = -5; }  
    }  
  }   
    
  // If ball hits paddle or back wall, reverse direction  
  if(ball_x < ball_size && ball_dir == -1) {  
    ball_dir *= -1;  
  }  
    
  // If the ball is touching top or bottom edge, reverse direction  
  if(ball_y > height-ball_size) {  
    dy = dy * -1; 
    resetrings(); 
  }  
  if(ball_y < ball_size) {  
    dy = dy * -1;  
  }  
  
  // Draw ball  
  fill(0);  
  ellipse(ball_x, ball_y, ball_size, ball_size);  
    
  // Draw the paddle  
  fill(0);  
  rect(width-dist_wall, paddle_y, paddle_width, paddle_height);    
}  


/*
int  ring_x;
int   ring_y;
float ringSize;
int  ringWidth = 5;
 
int    lastClick;
 
void  setup() {
    size(500, 400);
   resetRings(width/2, height/2, 0);
     stroke(0);
  noFill();
   lastClick = millis();
}
 
void    resetRings(int newX, int newY) {
  ring_x =  newX;
  ring_y  =  newY;
  ringSize = 0;
}  
 
void    mousePressed() {
  lastClick = millis();
     resetRings(mouseX, mouseY);
}
 
void    circle(int x, int y, int d) {
  ellipse(ring_x, ring_y,   d, d);
}
 
void    draw() {
  if (millis() - 1000 > lastClick) {
       resetRings(random(width), random(height));
       lastClick = millis();
  }
    
     background(255);
 
  ringSize = ringSize +  0.3;
  int   ringCount = 0;
  
  while  (ringCount < 5   && ringSize - ringCount * ringWidth*2 >  0) {
      circle(ring_x, ring_y, ringSize - ringCount *  ringWidth*2);
      ringCount = ringCount + 1;
  }
}

*/