After much confusion and some trial-and-error, I managed to stitch together equal-sized neighbor chunks along their faces. Selective debug drawing in Unity, along with some mostly unrelated doodles in Gimp, helped me track down and fix multiple off-by-one errors. The small, green planet with a tall, white building already looks a lot better:
Left to do:
- Stitch equal-sized chunks along edges (four chunks per seam)
- Stitch mixed-sized chunks along faces (two chunks per seam)
- Stitch mixed-sized chunks along edges (three or four chunks per seam)
Steps 1 and 2 shouldn't be too hard, but I dread taking step 3 with my current approach, which involves duplicating a lot of code per axis. There will be many different cases when stitching smaller chunks to larger ones.