How to make a Android controller

Just made a simple controller for processing for Android. I need help with the output in which I would like a angle instead of a x & y position as the out put

class Controller
{

int touches_on;
float d;

PVector right_mouse = new PVector(0,0);
PVector left_mouse = new PVector(0,0);

PVector right_mouse_output = new PVector(0,0);
PVector left_mouse_output = new PVector(0,0);

Controller(float D)
{
d = D;
}

void All ()
{

noFill();
strokeWeight(10);
stroke(100);

//start
if(touches.length == 0)
{
touches_on = 3;

}
//start for
for(int i = 0; i < touches.length; i++)
{
if( touches[i].y > height/2 && touches_on == 3 )
{
touches_on = i;
}
if(i == touches_on && touches[i].y > height/2)
{

     right_mouse.x = touches[i].x;
     right_mouse.y = touches[i].y;
     
     if(right_mouse.x  > d*0.75 + d/2){right_mouse.x = d*0.75+d/2;}
     else if(right_mouse.x  < d*0.75 - d/2){right_mouse.x = d*0.75-d/2;}
     if(right_mouse.y  > height-d*0.75 + d/2){right_mouse.y = height-d*0.75+d/2;}
     else if(right_mouse.y  < height-d*0.75 - d/2){right_mouse.y = height-d*0.75-d/2;}

     ellipse(right_mouse.x, right_mouse.y , d/2 , d/2); 
     
     right_mouse_output.x = right_mouse.x - d*0.75;
     right_mouse_output.y = height-d*0.75-right_mouse.y;
     
     
     
     
     
     
     } 
     else if(i != touches_on && touches[i].y < height/2)
     {
       
       left_mouse.x = touches[i].x;
       left_mouse.y = touches[i].y;
       
       

       if(left_mouse.x  > d*0.75 + d/2){left_mouse.x = d*0.75+d/2;}
       else if(left_mouse.x  < d*0.75 - d/2){left_mouse.x = d*0.75-d/2;}
    
    
    
       if(left_mouse.y  > d*0.75 + d/2){left_mouse.y = d*0.75+d/2;}
       else if(left_mouse.y  < d*0.75 - d/2){left_mouse.y = d*0.75-d/2;}

       ellipse(left_mouse.x , left_mouse.y , d/2, d/2);     
           
       
       left_mouse_output.x = left_mouse.x - d*0.75;
       left_mouse_output.y = left_mouse.y - d*0.75;
       
     
     }

//for end
}

ellipse(d * 0.75,d * 0.75, d, d);
ellipse(d * 0.75, height-d * 0.75, d, d);

//stop

//end
}

}