protected boolean needToRecalculateNormals() {
        if (affectedAreaBBox != null)
            return true;
        if (!lastScale.equals(getWorldScale())) {
            affectedAreaBBox = new BoundingBox(getWorldTranslation(), Float.MAX_VALUE, Float.MAX_VALUE, Float.MAX_VALUE);
            lastScale = getWorldScale();
            return true;
        }
        return false;
    }
Signal if the normal vectors for the terrain need to be recalculated.
Does this by looking at the affectedAreaBBox bounding box. If the bbox
exists already, then it will grow the box to fit the new changedPoint.
If the affectedAreaBBox is null, then it will create one of unit size.

@param changedPoint a location to include
jme3-terrain/src/main/java/com/jme3/terrain/geomipmap/TerrainQuad.java