Tile Z is now hypotenused to 1 rather than stretching to have Z of 1.

tools/asset/chunk/__main__.py

@@ -44,6 +44,7 @@ Usage:
 """
 
 import json
+import math
 import os
 import struct
 import sys
@@ -58,6 +59,10 @@ CHUNK_HEIGHT     = 16
 CHUNK_DEPTH      = 4
 CHUNK_TILE_COUNT = CHUNK_WIDTH * CHUNK_HEIGHT * CHUNK_DEPTH  # 1024
 
+# World-space Z distance of one Z-layer/story, in world-float space.
+# Must match WORLD_LAYER_HEIGHT in src/dusk/rpg/overworld/worldpos.h.
+WORLD_LAYER_HEIGHT = 1.0 / math.sqrt(2)
+
 CHUNK_MESH_COUNT_MAX = 10
 CHUNK_MESH_NAME_MAX  = 64
 
@@ -231,7 +236,10 @@ def build_terrain_verts(tiles_bytes):
                 sw, se, ne, nw = corners
                 buf += _tile_quad(
                     u0, u1, v0, v1, fx, fy,
-                    fz + sw, fz + se, fz + ne, fz + nw
+                    (fz + sw) * WORLD_LAYER_HEIGHT,
+                    (fz + se) * WORLD_LAYER_HEIGHT,
+                    (fz + ne) * WORLD_LAYER_HEIGHT,
+                    (fz + nw) * WORLD_LAYER_HEIGHT
                 )
     return bytes(buf)