Support up to 4 weightmap layers on terrain Add single internal function to create terrain of any size with optional heightmap and weightmap data pointers Bail out of creating new terrain if it already has been created, it's better to just create a new entity than to clean up the existing one Initialize weightmaps on new terrain using weightmap data if it exists, otherwise default to 255 on first layer, 0 on the rest Pass heightmap and weightmap data from managed to native. Ensure data arrays match terrain size Test loading weightmap data from png