float radijus = 30;
float xc, yc;
int bat = 65;

float xbrzina = 2;
float ybrzina = 2;

int xsmer = 1;
int ysmer = 1;

void setup() 
{
  size(640, 360);
  stroke(0);
  frameRate(30);
  strokeWeight(2);
  ellipseMode(RADIUS);
  noFill();
  xc = width / 3;
  yc = height / 3;
}

void robot(int x, int y, int l, int baterija) {
  ellipseMode(RADIUS);
  strokeWeight(2);
  fill(255);

  //glava
  rect(x, y, l, 2*l/3);

  //antena
  noFill();
  beginShape();
  vertex(x + l/2, y);
  vertex(x + l/2 + l/16, y - l/8);
  vertex(x + l/2 - l/16, y - l/8);
  vertex(x + l/2, y - l/4);
  endShape();
  fill(255, 0, 0);
  ellipse(x + l/2, y - l/4, l/24, l/24);
  fill(255);

  //oči
  ellipse(x + l/4, y + 2*l/9, l/10, l/10);
  ellipse(x + 3*l/4, y + 2*l/9, l/10, l/10);
  fill(0);
  ellipse(x + l/4 + l/24, y + 2*l/9 + l/24, l/24, l/24);
  ellipse(x + 3*l/4 - l/24, y + 2*l/9, l/24, l/24);
  fill(255);

  //usta
  rect(x + l/3, y + 9*l/24, l/3, 2*l/9);

  //vrat
  rect(x + l/2 - l/8, y + 2*l/3, l/4, l/16);
  rect(x + l/2 - l/16, y + 2*l/3 + l/16, l/8, l/16);
  rect(x + l/2 - l/8, y + 2*l/3 + l/8, l/4, l/16);

  //točak
  fill(0);
  ellipse(x + l/2, y + 4*l/6 + l, l/3, l/3);

  //trup
  fill(255);
  rect(x - l/8, y + 5*l/6, l + l/4, l);

  //baterija
  fill(255,0, 0);
  rect(x + l/8, y + 7*l/6, baterija, l/3);
  noFill();
  rect(x + l/8, y + 7*l/6, 3*l/4 - l/16, l/3);
  fill(0);
  rect(x + l/8 + 3*l/4 - l/16, y + 7*l/6 + l/9, l/16, l/9);
}

void draw() {
  background(220);
  xc = xc + xbrzina * xsmer;
  yc = yc + ybrzina * ysmer;

  int odbijanje = 0;
  if (xc > width-108 || xc < 12) {
    xsmer = -xsmer;
    odbijanje = 1;
  }

  if (yc > height-192 || yc < 28) {
    ysmer = -ysmer;
    odbijanje = 1;
  }
  
  if (odbijanje == 1)
    if (bat > 3)
      bat = bat  - 3;
    else {
      bat = 0;
      noLoop();
    }
    
  robot(int(xc), int(yc), 96, bat);
}