Expert TileMap architectures
Isometric Y-sort
TILE_SHAPE_ISOMETRIC + y_sort_enabled on parent and each TileMapLayer. Tune y_sort_origin on tall TileData.
TileMapPattern stamping
Capture with get_pattern(coords); stamp with set_pattern(position, pattern) — tile_pattern_stamper.gd.
[!CAUTION] Pattern stamp beats thousands of
set_cellcalls and preserves source_id/atlas/alternative.
Layer diff / save deltas
Iterate get_used_cells() on source vs target; sync differing source_id / atlas / alternative — persist deltas via tilemap_data_manager.gd.
Navigation
Paint nav polygons in TileSet; after runtime edits batch-rebuild regions — do not rebuild every single cell.