Describe what each theme slot is used for, and stop theming the farming seeds as rocks

README.md

@@ -112,7 +112,12 @@ is neither mapped to a slot nor listed in ignoredObjects in theme-slots.json.
 - **Add a slot to the root `theme-slots.json` only for a genuinely new role.**
   Every theme is missing it until someone fills it in the assets repository:
   those objects keep their placeholder art in the meantime, which is not an
-  error.
+  error. Give it a `description` saying what its objects do in the starters
+  and what fits it: the authors of themes choose its asset from it (the gun of
+  the FPS starters must shoot, a crop must grow from the soil).
+- **Map an object only to a slot whose description fits what it does.** A seed
+  planted in a plot is not a small rock: every theme would show a rock (or a
+  bone, or a wheel) instead. List it in `ignoredObjects` if no slot fits.
 - **List in `ignoredObjects`** what is not meant to be seen as art: the camera
   anchor cube, an invisible collision helper, the faceless player of a first
   person game.

examples/starting-expanded-first-person-farming/theme-slots.json

@@ -12,8 +12,6 @@
     "scene:Game Scene/Beet": "crop.b",
     "scene:Game Scene/Harvest_Seed_Beet": "prop.container",
     "scene:Game Scene/Harvest_Seed_Carrot": "prop.container",
-    "scene:Game Scene/Seed_Beet": "nature.rock.small",
-    "scene:Game Scene/Seed_Carrot": "nature.rock.small",
     "scene:Game Scene/Barn": "building.tower",
     "scene:Game Scene/SmallBarn": "building.tower",
     "scene:Game Scene/ChickenCoop": "building.tower",
@@ -69,6 +67,8 @@
     "object:Water3D::Water3D/AreaPlaceholder",
     "object:Terrain3D::Terrain3D/AreaPlaceholder",
     "object:Terrain3D::TerrainGrass/AreaPlaceholder",
-    "object:Terrain3D::ScatteredModels/AreaPlaceholder"
+    "object:Terrain3D::ScatteredModels/AreaPlaceholder",
+    "scene:Game Scene/Seed_Beet",
+    "scene:Game Scene/Seed_Carrot"
   ]
 }

examples/starting-first-person-farming/theme-slots.json

@@ -15,8 +15,6 @@
     "scene:Game Scene/Beet": "crop.b",
     "scene:Game Scene/Harvest_Seed_Beet": "prop.container",
     "scene:Game Scene/Harvest_Seed_Carrot": "prop.container",
-    "scene:Game Scene/Seed_Beet": "nature.rock.small",
-    "scene:Game Scene/Seed_Carrot": "nature.rock.small",
     "scene:Game Scene/Walls": {
       "front": "env.wall",
       "left": "env.wall",
@@ -29,6 +27,8 @@
     "effect:Game Scene//Effect2": "sky.day"
   },
   "ignoredObjects": [
-    "scene:Game Scene/Player"
+    "scene:Game Scene/Player",
+    "scene:Game Scene/Seed_Beet",
+    "scene:Game Scene/Seed_Carrot"
   ]
 }

scripts/lib/ThemeSlots.js

@@ -3,10 +3,11 @@ const path = require('path');
 const fs = require('fs').promises;
 
 /**
- * The vocabulary of slots a theme can fill, shared by every starter.
+ * The vocabulary of slots a theme can fill, shared by every starter. The
+ * description of a slot is what the authors of themes read to choose its asset.
  * @typedef {{
  *   version: number,
- *   slots: Array<{id: string, kind: ThemeSlotKind, label: string}>,
+ *   slots: Array<{id: string, kind: ThemeSlotKind, label: string, description: string}>,
  * }} ThemeSlotsVocabulary
  *
  * @typedef {'model' | 'texture' | 'material' | 'skybox' | 'color'} ThemeSlotKind

scripts/lib/__tests__/ThemeSlots.spec.js

@@ -11,13 +11,48 @@ const {
 const vocabulary = {
   version: 1,
   slots: [
-    { id: 'character.player', kind: 'model', label: 'Player character' },
-    { id: 'nature.tree', kind: 'model', label: 'Tree' },
-    { id: 'env.ground', kind: 'texture', label: 'Ground' },
-    { id: 'env.wall', kind: 'texture', label: 'Wall' },
-    { id: 'sky.day', kind: 'skybox', label: 'Daytime sky' },
-    { id: 'terrain.ground', kind: 'material', label: 'Terrain ground' },
-    { id: 'terrain.grass.tip', kind: 'color', label: 'Grass tip color' },
+    {
+      id: 'character.player',
+      kind: 'model',
+      label: 'Player character',
+      description: 'The character the player controls.',
+    },
+    {
+      id: 'nature.tree',
+      kind: 'model',
+      label: 'Tree',
+      description: 'The trees.',
+    },
+    {
+      id: 'env.ground',
+      kind: 'texture',
+      label: 'Ground',
+      description: 'The texture of the ground.',
+    },
+    {
+      id: 'env.wall',
+      kind: 'texture',
+      label: 'Wall',
+      description: 'The texture of the walls.',
+    },
+    {
+      id: 'sky.day',
+      kind: 'skybox',
+      label: 'Daytime sky',
+      description: 'The sky.',
+    },
+    {
+      id: 'terrain.ground',
+      kind: 'material',
+      label: 'Terrain ground',
+      description: 'The main ground of a terrain.',
+    },
+    {
+      id: 'terrain.grass.tip',
+      kind: 'color',
+      label: 'Grass tip color',
+      description: 'The color of the grass blades at their tip.',
+    },
   ],
 };