A tile gains Collision scale: below 1 each blocking cell pulls in on the sides without a blocking neighbour and stays flush towards its neighbours, so a wall of bushes becomes a narrower wall without gaps and the inner corner of an L closes cleanly; above 1 the cell grows at its open sides; on several layers the largest value counts, and the merged rectangles work in fractions of a cell with exactly the old result at 1 (#140)

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/core/properties/PropertySchema.ts

@@ -20,7 +20,15 @@ import {
   type VariableKind,
 } from './kinds';
 import { findAssetOf, type Project } from '../model/Project';
-import { TILE_FPS_KEY, TILE_KIND_KEY, TILE_PLAYBACK_KEY, TILE_SOLID_KEY } from '../model/tile';
+import {
+  TILE_COLLISION_SCALE_KEY,
+  TILE_COLLISION_SCALE_MAX,
+  TILE_COLLISION_SCALE_MIN,
+  TILE_FPS_KEY,
+  TILE_KIND_KEY,
+  TILE_PLAYBACK_KEY,
+  TILE_SOLID_KEY,
+} from '../model/tile';
 import { TILEMAP_COLUMNS_KEY, TILEMAP_MAX_CELLS, TILEMAP_ROWS_KEY, TILEMAP_TILE_KEY } from '../model/tilemap';
 import { SLICE_SCALE_KEY } from '../model/texture';
 import type { SceneObject } from '../model/SceneObject';
@@ -249,6 +257,17 @@ const ASSET_SCHEMAS: Record<AssetType, PropertySchema> = {
     },
     // Solid is what the tile *is* – water, a wall – so it holds wherever the tile lies (#132).
     { key: TILE_SOLID_KEY, label: 'Solid', kind: 'boolean', default: false },
+    // Below 1 a cell blocks less than its square, above 1 more – but only on the sides without a
+    // blocking neighbour, so a wall of such cells stays closed (#140).
+    {
+      key: TILE_COLLISION_SCALE_KEY,
+      label: 'Collision scale',
+      kind: 'number',
+      default: 1,
+      min: TILE_COLLISION_SCALE_MIN,
+      max: TILE_COLLISION_SCALE_MAX,
+      step: 0.05,
+    },
   ],
   // The layers and their cells are intrinsic data on the asset (see TilemapAsset); these three say
   // how far the grid reaches and how big one cell is drawn. A tile's own pictures are scaled onto