As the title says, an option to limit threads dedicated to map view generation.

It would be useful especially when loading the terrain on the map view, since obviously it takes more threads and longer to load the map. then the biome view. However, right now it uses 100% of threads to generate the heightmap. It's problematic since it can limit other processes such as videos and OS processes in the background.

Therefore, a toggabale option to limit map view generation to say, 2 or 3 threads, instead of using all the threads, would be useful. Perhaps it can also be tied to the thread option used for the seed finder.

It could also apply to exporting biomes to image with heightmap.