i have this proccesing project and i need to insert a menu so the user can change the shape of the circles to triangles and squares and i can manage it... so i could use some help... 

void setup(){

size(900,400);

frameRate(250);

background(0);

stroke(0,250);

ellipseMode(CENTER);

smooth();

}

 

float a,b,c;

void draw() {

stroke(255);

 

a=sqrt(b*b+c*c);

b=abs(pmouseX-mouseX);

c=abs(pmouseY-mouseY);

float d= noise(1)*mouseX;

float f= noise(2)*mouseY;

 

fill(f,d,a,25);

 

if (mousePressed) {

  fill(f,d,a); 

}

   

   

ellipse (mouseX, mouseY,a*a,a*a);

}

void keyPressed() {

background(255);

}