Add shared-scene 2D authoring, sprite animation and Rapier2D physics

docs/COMMANDS.json

@@ -4,7 +4,8 @@
   "commands": {
     "project.rename": "{name}",
     "project.settings": "{background:\"#dedbd2\",ambient:0.85,shadows:true,renderScale:1}",
-    "scene.create": "{id?,name}",
+    "scene.create": "{id?,name,mode?:2d|3d}",
+    "scene.configure": "{sceneId?,mode:2d|3d}; default editor view and fallback game camera",
     "scene.activate": "{id}",
     "scene.rename": "{sceneId,name}",
     "node.create": "{name,id?,position?,parentId?,components?,sceneId?} OR {entity:{id,name,parentId:null,enabled:true,transform:{position:[0,0,0],rotation:[0,0,0],scale:[1,1,1]},components:{}}}",
@@ -14,13 +15,113 @@
     "node.duplicate": "{id,sceneId?}; subtree and internal references",
     "component.set": "{id,type,value,sceneId?}; replaces component",
     "component.remove": "{id,type,sceneId?}",
-    "asset.upsert": "{asset:{id,name,kind:\"model\"|\"geometry\"|\"prefab\",uri?,geometry?,entities?,metadata?}}",
+    "asset.upsert": "{asset:{id,name,kind:\"model\"|\"geometry\"|\"prefab\"|\"image\",uri?,geometry?,entities?,metadata?,image?}}",
     "asset.delete": "{id}; fails if referenced",
     "script.upsert": "{script:{id,name,source,fields:{speed:{type:\"number\",default:5,label:\"Speed\",min:0,max:30}}}}",
     "prefab.create": "{id,name?,sceneId?}",
     "prefab.instantiate": "{assetId,position?,sceneId?}"
   },
   "components": {
+    "sprite": {
+      "assetId": "image asset or empty for white quad",
+      "frame": 0,
+      "size": "optional [width,height], otherwise frame pixels / PPU",
+      "color": "#ffffff",
+      "alpha": 1,
+      "layer": 0,
+      "order": 0,
+      "flipX": false,
+      "flipY": false,
+      "sortY": false,
+      "lit": false
+    },
+    "spriteAnimator": {
+      "autoplay": "idle",
+      "autoStates": false,
+      "clips": [
+        {
+          "name": "idle",
+          "frames": [
+            0,
+            1
+          ],
+          "fps": 8,
+          "loop": true
+        }
+      ]
+    },
+    "tilemap": {
+      "assetId": "image asset",
+      "tileSize": [
+        1,
+        1
+      ],
+      "width": 32,
+      "height": 18,
+      "cells": [
+        {
+          "x": 0,
+          "y": 0,
+          "frame": 0,
+          "solid": true
+        }
+      ],
+      "collisions": false,
+      "layer": 0,
+      "order": 0
+    },
+    "collider2d": {
+      "shape": "box | circle | capsule | polygon",
+      "size": [
+        1,
+        1
+      ],
+      "radius": 0.5,
+      "height": 1.8,
+      "points": "convex polygon vertices [[x,y],...]",
+      "offset": [
+        0,
+        0
+      ],
+      "sensor": false,
+      "oneWay": false,
+      "membership": 1,
+      "mask": 65535
+    },
+    "rigidbody2d": {
+      "type": "fixed | dynamic | kinematic",
+      "mass": 1,
+      "friction": 0.5,
+      "restitution": 0,
+      "gravityScale": 1,
+      "lockRotation": true,
+      "ccd": true,
+      "requires": "collider2d or colliding tilemap"
+    },
+    "character2d": {
+      "mode": "platformer | topDown",
+      "controls": true,
+      "speed": 5,
+      "jumpSpeed": 8,
+      "gravity": 20,
+      "autostep": 0.2,
+      "requires": "kinematic rigidbody2d + collider2d"
+    },
+    "joint2d": {
+      "type": "fixed | revolute | rope | spring",
+      "targetId": "another body2d",
+      "anchor": [
+        0,
+        0
+      ],
+      "targetAnchor": [
+        0,
+        0
+      ],
+      "length": 1,
+      "stiffness": 50,
+      "damping": 5
+    },
     "mesh": {
       "type": "box | sphere | cylinder | icosphere | torus | model | geometry | custom",
       "size": [
@@ -61,7 +162,10 @@
       "restitution": 0.1
     },
     "camera": {
-      "mode": "follow | firstPerson",
+      "mode": "follow | firstPerson | fixed | imported | 2d",
+      "orthoWidth": 20,
+      "pixelPerfect": false,
+      "pixelsPerUnit": 100,
       "targetId": "subject",
       "offset": [
         0,