Button

int x=50;

int y=50; 

​

void setup() {

  size(400,400);

}

boolean  backgroundisPURPLE= false; 

​

void draw() {

  if (backgroundisPURPLE ==true){

  background(58,67,153); //PURPLE

    ellipse (x+50,y+50,30,30); 

  x= x+5;

    ellipse (x+100,y+50,50,50); 

  x= x+5;

      ellipse (x,y+50,50,50); 

  y= y+5;

  }else{

    background(241,249,0); //YELLOW 

fill(0,255,33);

if ((mouseX>width/2)&&(mouseY<height/2))

ellipse(width/2+width/4,height/4,100,100);   

fill(255,255,255);

if((mouseX>width/2)&&(mouseY>height/2))

ellipse(width/2+width/4,height/2+height/4,100,100);   

  ellipse (x,y,20,20); 

  x= x+2;

}  }

void mousePressed (){

  if (backgroundisPURPLE == true){

    backgroundisPURPLE = false;

  } else {

    backgroundisPURPLE = true;

  }

}

void mouseDragged(){

  fill(232,9,12);

  ellipse (x+50,y-10,100,100); 

}