You could interpolate and make the grid smaller. Basically the idea would be to take those large squares and make them smaller so that the edges are not so obvious.

I posted the algorithm here with an example and some pretty pictures:

Creating colour spectrum by light flux values

Essentially, you would have to take your generated map data array -- and then just stretch it out over a larger map array, making the edges look a lot smoother. This would be an alternative approach to utilizing bitmasking.

Considering you are already converting your map into a mesh, I would assume this wouldn't be much of a performance hit during gameplay, so as long as you pre-calculate it all during the map creation portion.

Edit Alternatively to this -- you could also just sample a larger dataset so that your world is larger to begin with.

You could interpolate and make the grid smaller. Basically the idea would be to take those large squares and make them smaller so that the edges are not so obvious.

I posted the algorithm here with an example and some pretty pictures:

Creating colour spectrum by light flux values

Essentially, you would have to take your generated map data array -- and then just stretch it out over a larger map array, making the edges look a lot smoother. This would be an alternative approach to utilizing bitmasking.

Considering you are already converting your map into a mesh, I would assume this wouldn't be much of a performance hit during gameplay, so as long as you pre-calculate it all during the map creation portion.

Edit Alternatively to this -- you could also just sample a larger dataset so that your world is larger to begin with.