Hello,

Hello,
I've got a performance related question. I've made a test program in Processing and Java, but I don't unterstand the result of  the Processing sketch. There are three types of functions:
1) swaps two array values -> swap()
2 ) 1 + returns the array -> swap2()
3) 2 + assigns the result to the old array -> a = swap2()

The result in Java ( as expected from fastest to slowest): swap() -> swap2() -> a = swap2()
The result in Processing: a = swap2() -> swap2() -> swap() ( = reversed)

Can anyone explain me this behaviour or did I made a silly mistake?
Thanks in advance.

Results in Processing (10 tries):



Java:

1. 
   public class Test {
   
       static int n = 100000000;
       static int[] a = {
         1, 2
       };
       static long std;
   
      
       static void swap(int[] vals) {
             int tmp = vals[0];
             vals[0] = vals[1];
             vals[1] = tmp;
           }
   
           static int[] swap2(int[] vals) {
             int tmp = vals[0];
             vals[0] = vals[1];
             vals[1] = tmp;
             return vals;
           }
      
       public static void main(String[] args) {
   
               std = System.currentTimeMillis();
             for (int i = 0; i < n; i++)
               a = swap2(a);
             System.out.println(System.currentTimeMillis() - std);
            
             std = System.currentTimeMillis();
             for (int i = 0; i < n; i++)
               swap2(a);
             System.out.println(System.currentTimeMillis() - std);
   
               std = System.currentTimeMillis();
             for (int i = 0; i < n; i++)
               swap(a);
             System.out.println(System.currentTimeMillis() - std);
   
             System.exit(0);
   
       }
   
   }
   
   

Processing:

1. int n = 100000000;
   int[] a = {
     1, 2
   };
   long std;
   
   void swap(int[] vals) {
     int tmp = vals[0];
     vals[0] = vals[1];
     vals[1] = tmp;
   }
   
   int[] swap2(int[] vals) {
     int tmp = vals[0];
     vals[0] = vals[1];
     vals[1] = tmp;
     return vals;
   }
   
   void setup() {
   
       std = millis();
     for (int i = 0; i < n; i++)
       a = swap2(a);
     println(millis() - std);
    
     std = millis();
     for (int i = 0; i < n; i++)
       swap2(a);
     println(millis() - std);
   
       std = millis();
     for (int i = 0; i < n; i++)
       swap(a);
     println(millis() - std);
   
     exit();
   }
   

Is it possibly to change a shader in a running sketch?
For example:

1. void setup() {
2. ...
3. shader1 = loadShader(PShader.FLAT, "shader1.glsl");
4. shader2 = loadShader(PShader.FLAT, "shader2.glsl");
5. shader(shader1);
6. ...
7. }
8. void keyReleased() {
9.  shader(shader2);
10. }

Thanks in advance.

1. ControlP5 controlP5 = new ControlP5(this);
    controlP5.setAutoDraw(false);
   

When I use

1. controlP5.draw()
   

in draw() with any Renderer, I get an NullPointerException. I don't know which part of my code causes the Exception, so I try to describe what I'm using.
In the sketch I use Jbox2D and for ControlP5 a ControlFont.In setup() I also added a MouseWheelListener.
Thanks in advance.