Javadoc
CombinerHeightMap
generates a new height map based on
two provided height maps. These had maps can either be added together
or subtracted from each other. Each heightmap has a weight to
determine how much one will affect the other. By default it is set to
0.5, 0.5 and meaning the two heightmaps are averaged evenly. This
value can be adjusted at will, as long as the two factors are equal
to 1.0.