i want to rotate the controlP5.Button b but it didn't work,  hope someone could help me 

2. import controlP5.*;
3. ControlP5 controlP5;
4. controlP5.Button b;
5. Textarea myTextarea;
6.  ControllerSprite sprite;
7. void setup() {
8.   size(1000,1000);
9.   smooth();
10.   controlP5 = new ControlP5(this);  
11.   sprite = new ControllerSprite(controlP5,loadImage("flowers.jpg"),132,180); 
12.   b = controlP5.addButton("image",100,20,40,100,100); 
13.   b.setSprite(sprite);  
14.   fill(0);
15.   noStroke();
16.   myTextarea = controlP5.addTextarea("txt")
17.                   .setPosition(200,20)
18.                   .setSize(200,200)
19.                   .setFont(createFont("arial",12))
20.                   .setLineHeight(14)
21.                   .setColor(color(128))
22.                   .setColorBackground(color(255,100))
23.                   .setVisible(true)
24.                   .setColorForeground(color(255,100));
25.                   ;
26.   myTextarea.setText("Lorem Ipsum is simply dummy text of the printing and typesetting"
27.                     +" industry. Lorem Ipsum has been the industry's standard dummy text"
28.                     +" ever since the 1500s, when an unknown printer took a galley of type"
29.                     +" and scrambled it to make a type specimen book. It has survived not"
30.                     +" only five centuries, but also the leap into electronic typesetting,"
31.                     +" remaining essentially unchanged. It was popularised in the 1960s"
32.                     +" with the release of Letraset sheets containing Lorem Ipsum passages,"
33.                     +" and more recently with desktop publishing software like Aldus"
34.                     +" PageMaker including versions of Lorem Ipsum."
35.                     );
36. }
37.  
38. void draw() {
39.   background(0); // black background
40.   pushMatrix();
41.   translate(width/2, height/2);
42.   rotate(PI/2);
43.   fill(255);rect(200,40, 80, 50, 15, 15);
44.   //b.setPosition(400,300) ; //in this part i tried to rotate the button but it didn't work
45.   if(controlP5.isMouseOver(controlP5.getController("image"))){
46.     myTextarea.setVisible(true);
47.   }
48.   else{myTextarea.setVisible(false);}
49.    popMatrix();
50. }
51.  
52. 
    
53. 
    
54. void controlEvent(ControlEvent theEvent) {  
55.   if(theEvent.isController()) {
56.     print("control event from : "+theEvent.controller().name());
57.     println(", value : "+theEvent.controller().value());
58.   }
59.   
60. }