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static variable doesn't change


I started using jMonekyEngine and it's easy way of interacting with Swing GUI. Following their tutorial here http://jmonkeyengine.org/wiki/doku.php/jme3:advanced:swing_canvas

It all works and I get everything loaded,however I'm having trouble modifying things.

According to their tutorial, the constant update and happens here:

public void simpleUpdate(float tpf) {
    geom.rotate(0, 2 * tpf, 0);
}

(this is an example from the tutorial on rotating objects). what i'm trying to do is just increasing and decreasing the speed of rotation (by changing the 2 or tpf with a variable which gets update inside an ActionListener in the Swing gui.

However, since in their tutorial they stated that the swing gui is to be created inside the main method, I have to create a variable which is static in order to change it.

static float rotate = 0.0f;

it gets modified inside the main method, but when trying to use it like so:

public void simpleUpdate(float tpf) {
    geom.rotate(0, rotate * tpf, 0);
}

it remains constant to the initial value. I tried creating a GUI class to build the gui (extends JPanel) and using getters and setters, but still not go.. Any help would be appreciated! Thanks!

EDIT: Here's how I change the rotate value:

JButton faster = new JButton("Faster");
faster.addActionListener(new ActionListener() {

    @Override
    public void actionPerformed(ActionEvent arg0) {
        rotate +=0.1f;
    }
});

inside the main method. rotate is a static field.


Solution

  • This is working for me

    http://test.jmonkeyengine.org/wiki/doku.php/jme3:beginner:hello_main_event_loop http://test.jmonkeyengine.org/wiki/doku.php/jme3:beginner:hello_input_system?s[]=input

    Is your action listener really triggering the event on click? maybe you have a problem there and not in the rotate variable. Note that I'm not using swing on this example..

    import com.jme3.app.SimpleApplication;
    import com.jme3.input.KeyInput;
    import com.jme3.input.controls.ActionListener;
    import com.jme3.input.controls.KeyTrigger;
    import com.jme3.material.Material;
    import com.jme3.math.ColorRGBA;
    import com.jme3.math.Vector3f;
    import com.jme3.scene.Geometry;
    import com.jme3.scene.shape.Box;
    
    /** Sample 4 - how to trigger repeating actions from the main update loop.
     * In this example, we make the player character rotate. */
    public class HelloLoop extends SimpleApplication {
    
        public static void main(String[] args){
            HelloLoop app = new HelloLoop();
            app.start();
        }
    
        protected Geometry player;
    
        @Override
        public void simpleInitApp() {
    
            Box b = new Box(Vector3f.ZERO, 1, 1, 1);
            player = new Geometry("blue cube", b);
            Material mat = new Material(assetManager,
              "Common/MatDefs/Misc/Unshaded.j3md");
            mat.setColor("Color", ColorRGBA.Blue);
            player.setMaterial(mat);
            rootNode.attachChild(player);
    
            initKeys();
        }
    
        /* This is the update loop */
        @Override
        public void simpleUpdate(float tpf) {
            // make the player rotate
            player.rotate(0, val*tpf, 0); 
        }
        float val = 2f;
        private void initKeys() {
            // Adds the "u" key to the command "coordsUp"
            inputManager.addMapping("sum",  new KeyTrigger(KeyInput.KEY_ADD));
            inputManager.addMapping("rest",  new KeyTrigger(KeyInput.KEY_SUBTRACT));
    
            inputManager.addListener(al, new String[]{"sum", "rest"});
        }
          private ActionListener al = new ActionListener() {
            public void onAction(String name, boolean keyPressed, float tpf) {
              if (name.equals("sum") ) {
                  val++;
              }else if (name.equals("rest")){
                  val--;
              }
            }
          };
    }