I also tried using this  Layers library, but for some reason it doesn't work when combined with the SimpleOpenNi library in one sketch. It leaves the whole applet window white, except for a top-left 100*100 square portion which functions properly. Both libraries and all the code I'm using with them work individually, but just not together for some weird reason... 

I don't expect to be able to solve this problem myself, as it seems like an issue with the source code, or that they're simply incompatible with each other, so I'm wondering if anyone else knows of any other options to achieve this? Any tips/ideas would be awesome. 

This is my main sketch:

2. /OPENNI
3. import SimpleOpenNI.*;
4. SimpleOpenNI  context;
5. 
   
6. //LAYERS
7. import com.nootropic.processing.layers.*;
8. AppletLayers layers;
9. 
   
10. 
    
11. void setup() {
12. 
    
13.   //LAYERS
14.   layers = new AppletLayers(this);
15.   drawing m = new drawing(this);
16.   layers.addLayer(m); 
17. 
    
18.   //CAM PARAMS
19.   // instantiate a new context
20.   context = new SimpleOpenNI(this);
21. 
    
22.   // enable depth image generation 
23.   context.enableDepth();
24.   //  context.enableRGB(640,480,30);
25. 
    
26.   // create a window the size of the depth information
27.   size(context.depthWidth(), context.depthHeight()); 
28.   //  size(context.rgbWidth(),context.rgbHeight()); 
29. 
    
30.   //DRAW PARAMS
31.   //  size(displayWidth,displayHeight);
32.   fill(0, 0, 255);
33.   noStroke();
34.   smooth();
35.   noCursor();
36.   frameRate(50);
37.   background(0);
38. }
39. 
    
40. 
    
41. //THIS VOID PAINT IS NECESSARY FOR THE LAYERS LIBRARY TO WORK PROPERLY
42. void paint(java.awt.Graphics g) {
43.   // This method MUST be present in your sketch for layers to be rendered!
44.   if (layers != null) {
45.     layers.paint(this);
46.   } else {
47.     super.paint(g);
48.   }
49. }
50. 
    
51. void draw() {
52. 
    
53.   //CAM
54.   // update the camera
55.   context.update();
56. 
    
57.   // draw depth image
58.   image(context.depthImage(), 0, 0);
59. }

and the class:

2. class drawing extends Layer {
3. 
   
4.   drawing(PApplet parent) {
5.     super(parent); // This is necessary!
6.   }
7. 
   
8.   void draw() {
9.     fill(0, 0, 255);
10.     noStroke();
11.     smooth();
12.     noCursor();
13. //    frameRate(50);
14.     // background(0, 0); // clear the background every time, but be transparent
15. 
    
16.     //DRAW
17.     ellipse(mouseX, mouseY, 10, 10);
18.     if (mousePressed == true) {
19.       ellipse(mouseX, mouseY, 10, 10);
20.     }
21.   }
22. }

Also, a kinect is needed to run the sketch properly, but if anyone can find a problem in the code anyway, that'd be amazing. Thanks in advance

I have this if statement:

The player2 class (relevant variables in red):

The enemy1 class:

The if statement gets highlighted when I run the sketch with "NullPointerException", and the following message:

Why? What do I have to do for this to work? In the player2 class, I'm using .png sprites to animate the player's movement (up down left right). In the enemy1 class, 'jellyfish' is an animated gif being called with the gifAnimation library, and they're also being called in an arrayList. Any ideas on the source of the issue?

I'd post the whole sketch but it's all a huge mess and I don't want to confuse anyone who might be able to spot the issue without it. Any tips at all would be greatly appreciated!