Any tips for keeping meshes tileable? Thread

I made my heightmap 4096x4096 and broke it into 16x 1024x1024 chunks and made a mesh from each heightmap. But after adding the "smooth" shading option it rounds them to the point they don't line up perfectly, it's close but not great...

So I was wondering if I should be making a single mesh from the heightmap, and somehow split it into my 16 meshes in Blender after displacing it and smoothing the whole thing....

So say I'm overhead, can I select equal sized squares and cut them up? What term should I be looking up, I'm nub at modeling but can do heightmaps and some basic inanimate objects.. How would you go about it? It's for mobile so I want to make the terrains in chunks so I can cull ones not being rendered.

EDIT:: The almighty "P" key splits the selection into an object how I want. If I split it only into 4 sections it re-aligns perfectly but if I try to make more chunks they don't line up right.

Edited by: shindig

I know tileable meshes, where this problem can occur only during baking. My best guess however, is to first smooth the terrain and then create the chunks. Perhaps you can export the heightmap and tweak it in Photoshop? Isn't there some kind of import option that lets you create the chunks in a modeling program, cut them up there and import to Unity?

That should be more accurate than drawing/fixing a hightmap, too. Just take a 4k plane, subdivide it x16 or to any power of 2 size. Activate proportional transformation and pull out the polygons that are your mountaintops. If you want, add smoothing/subdivision. Then put a planar projection X/Z on it. Look for rendermaps in the software and then render out a heightmap of the piece. Cut that into chunks and it should work, imo.

Edited by: SinKing

I figured it out somewhat. If I only cut it into a 4 chunks it fits back together perfectly, but when I tried to cut it into 12 chunks after smoothing it didn't fit back together. I dunno if unity changed it when I generate colliders/lightmap uvs, or it loses a row of vertex points when I split it, but if I split it into 4 chunks it goes together well enough.

I made the heightmap in photoshop and just magic wand the different colors, copy from a texture layer and past it to quickly make the base texture. Then can add ground features like stones, mud, etc onto the texture in photoshop.

I'll try the steps you list.

Here's a first draft for a top down map:

Edited by: shindig