anchor.diff:  vec4 lightDir = vec4(-0.577350, -0.577350, -0.577350, 0);
   
   uniform mat4 projectionMatrix;
  +uniform mat4 cameraMatrix;
   uniform mat4 modelMatrix;
   
   void main()
   {
     // add a temporary model and view transform
  -  vec4 modelPos = modelMatrix * in_Position - vec4(0.25, 0.75, 0.0, 0.0);
  +  vec4 modelPos = cameraMatrix * modelMatrix * in_Position;
     gl_Position = projectionMatrix * modelPos;
     float intense = max(dot(-in_Normal, lightDir.xyz), 0.0);
     theColor = intense * in_Color;
  
positive.code:               (if (eq (projection-type window) 'orthographic)
                    'perspective
                    'orthographic))
          (setf (projection-matrix *proj-uset*)
                (compute-projection-matrix window (projection-type window) 1.0 10.0))
          (draw-window window))
        (call-next-method)))
  
negative.code:                            :shaders (list (make-instance 'lpsg:shader
                                                           :shader-type :vertex-shader
                                                           :source *vertex-shader-source*
                                                           :usets '(camera model))
                                            (make-instance 'lpsg:shader
                                                           :shader-type :fragment-shader
                                                           :source *fragment-shader-source*
  