anchor.diff:  
   When you deal with complex game engine features like animations or physics it is handy to get feedback from the engine how it interpreted the current state. Is the physical object's collision shape really where you think it is? Is the skeleton of the animated character moving like you think it should? This document shows you how to activate visual debug aides.
   
  -What if you just want to quickly write code that loads models and brings them in their start position? You may not want to hunt for a sample model, convert it, add lights, and load materials. Instead you use “hasslefree simple shapes, and a “hasslefree unshaded material or wireframe: No model, no light source, no materials are needed to see them in your test scene.
  +What if you just want to quickly write code that loads models and brings them in their start position? You may not want to hunt for a sample model, convert it, add lights, and load materials. Instead you use "`hasslefree`" simple shapes, and a "`hasslefree`" unshaded material or wireframe: No model, no light source, no materials are needed to see them in your test scene.
   
   If you ever have problems with objects appearing in the wrong spot, with the wrong scale, or wrong orientation, simply attach debug shapes to your scene to have a point of reference in 3D space – just like a giant ruler. If your code positions the debug shapes correctly, but models remain invisible when you apply the same code to them, you know that the problem must be either the model (where is its origin coordinate?), or the light (too dark? too bright? missing?), or the model's material (missing?) – and not the positioning code.
   
  
positive.code: 
  Making the skeleton visible inside animated models can be handy for debugging animations. The `control` object is an AnimControl, `player` is the loaded model.
  
  [source,java]
  ----
  
  
negative.code: 
  === Coordinate Axes
  
  The coordinate axes (com.jme3.scene.debug.Arrow) help you see the cardinal directions (X,Y,Z) from their center point. Scale the arrows to use them as a "`ruler`" for a certain length.
  
  [source,java]
  ----
  
  private void attachCoordinateAxes(Vector3f pos) {
      Arrow arrow = new Arrow(Vector3f.UNIT_X);
      putShape(arrow, ColorRGBA.Red).setLocalTranslation(pos);
  
      arrow = new Arrow(Vector3f.UNIT_Y);
      putShape(arrow, ColorRGBA.Green).setLocalTranslation(pos);
  
      arrow = new Arrow(Vector3f.UNIT_Z);
      putShape(arrow, ColorRGBA.Blue).setLocalTranslation(pos);
  }
  
  private Geometry putShape(Mesh shape, ColorRGBA color) {
      Geometry g = new Geometry("coordinate axis", shape);
      Material mat = new Material(assetManager, "Common/MatDefs/Misc/Unshaded.j3md");
      mat.getAdditionalRenderState().setWireframe(true);
      mat.getAdditionalRenderState().setLineWidth(4);
      mat.setColor("Color", color);
      g.setMaterial(mat);
      rootNode.attachChild(g);
      return g;
  }
  ----
  
  