I am manipulating geometry with analog input via Arduino [Potenometer]. This is working with the exception of the geometry is being added on top of old sets when ideally I would like it to be visualized as a manipulation of the surface.

I've placed a photo to describe in more detail...

I am new to processing/arduino so please bare with me.

Here is the code:

2. import processing.opengl.*;
3. import igeo.*;
4. import processing.serial.*;
5. Serial port;
6.   float var = 0;
7.   int rvar = round(var);
8. 
   
9.   
10. void setup()
11. {
12.   size(500,500, IG.GL );
13.   port = new Serial(this, "COM3", 9600);
14.   port.bufferUntil('\n');
15. 
    
16. }
17. void draw()
18. 
    
19. {
20.   // 4 points in u direction, 3 points in v direction
21. double[][][] controlPoints = 
22.   {{{ 0, 0, 0},    { 10, 0, var},    { 20, 0, 0}},
23.    {{ 0, 10, var}, { 10, 10, var*2}, { 20, 10, var}}, 
24.    {{ 0, 20, var}, { 10, 20, var*2}, { 20, 20, var}},
25.    {{ 0, 30, 0},   { 10, 30, var},   { 20, 30, 0}}};
26. 
    
27. // u degree = 3, v degree = 2
28. new ISurface(controlPoints, 3, 2).clr(1,.8,0);
29. }
30. 
    
31. void serialEvent (Serial port)
32. {
33.   var = float(port.readStringUntil('\n')); 
34. }
35.