anchor.diff:        vPosition = uMVMatrix * vec4(aVertexPosition, 1.0);
         gl_Position = uPMatrix * vPosition;
         vTextureCoord = aTextureCoord;
  -      vNormal = uNMatrix * aVertexNormal;
  +      vNormal = uIdentMatrix * aVertexNormal;
       }
       """;
   
  
positive.code: 
      _uPMatrix = _gl.getUniformLocation(_shaderProgram, "uPMatrix");
      _uMVMatrix = _gl.getUniformLocation(_shaderProgram, "uMVMatrix");
      _uNMatrix = _gl.getUniformLocation(_shaderProgram, "uNMatrix");
      _uSampler = _gl.getUniformLocation(_shaderProgram, "uSampler");
      _uUseLighting = _gl.getUniformLocation(_shaderProgram, "uUseLighting");
      _uAmbientColor = _gl.getUniformLocation(_shaderProgram, "uAmbientColor");
  
negative.code:     wsegments.add(new Segment(new Vector2( 0.0,-2.0), new Vector2(-0.5,-2.0)));
      wsegments.add(new Segment(new Vector2(-0.5,-2.0), new Vector2(-1.0,-1.0)));
      
      ftiles.add(new FloorTile(new Vector2(-1.0,-2.0), new Vector2(-1.0, 1.0), new Vector2(1.0,1.0), new Vector2(1.0,-2.0)));
      
      
      rendergroups[textures["./assets/trak5/tile2a.png"]].renderables = wsegments;
  