diff --git a/schema/tool/blender-xrfragments.awk b/schema/tool/blender-xrfragments.awk
index 8e99210..c5c07de 100755
--- a/schema/tool/blender-xrfragments.awk
+++ b/schema/tool/blender-xrfragments.awk
@@ -3,19 +3,21 @@ BEGIN {
   REPLACE=1
   state=0
   while( (getline < "./tool/blender-xrfragments.py") > 0 ){
-    if( $1 ~ /^}/ && state == REPLACE ) state=0
-
-    print $0
-
-    if( state == REPLACE ){
-      while( (getline < "./xrfragment-engine-prefixes.json") > 0 ){
-        gsub("true","True",$0)
-        gsub("false","False",$0)
-        if( $1 == "\"$version\":" ) $2 = ($2+1)","  # bump version
-        if( $0 !~ /^[{}]/ ) print $0
-      }
+    if( $0 ~ /^}/ && state == REPLACE ){ 
+      print $0
+      state=0
     }
 
-    if( $1 == "SCHEMA"               ) state=REPLACE
+    if( state == REPLACE ){
+      gsub("True","true",$0)
+      gsub("False","false",$0)
+      if( $1 == "\"$version\":" ) $2 = ($2+1)","  # bump version
+      if( $0 !~ /^[{}]/ ) print $0
+    }
+
+    if( $1 == "SCHEMA" ){
+      state=REPLACE
+      print "{"
+    }
   }
 }
diff --git a/schema/tool/blender-xrfragments.py b/schema/tool/blender-xrfragments.py
index 9582b6c..bfcdf2e 100644
--- a/schema/tool/blender-xrfragments.py
+++ b/schema/tool/blender-xrfragments.py
@@ -3,495 +3,487 @@ import json
 
 # --- 1. SCHEMA ---
 SCHEMA = {
+    "title": "XR Fragments",
+    "type": "object",
+    "$version": 2,
+    "flatten": True,
+    "$defs": {
 
-  "$schema": "https://json-schema.org/draft/2020-12/schema",  
-  "$id": "https://xrfragment.org/schema/xrfragment-engine-prefixes.json",
-  "$version": 35,
-  "title": "XR Fragments Engine Prefixes",
-  "type": "object",
-  "flatten": True,
+      "xrf":{
+        "title": "XR Fragments",
+        "description": "XR Fragments (level2) promotes embedding clickable hyperlinks\nin 3D files (via the href attribute).\nMake sure to check 'custom attributes' in your export dialog.",
+        "url": "https://xrfragment.org/#How%20it%20works",            
+        "properties":{
+          "_xrf-type": { "title": "type", "type": "string", "default":"xrf", "description": "needed for blender UI"},
+          "href":{
+            "type":"object.name",
+            "description": "teleport to / href"
+            }           
+          }
+        },   
 
-  "properties": {
-    "engine": {
-      "type": "enum",
-      "enum": [
-        ["NONE", "-- Select --", ""], 
-        ["JANUSXR", "JanusXR", ""], 
-        ["THREEJS", "Three.js", ""],
-        ["GODOT3", "Godot 3", ""],
-        ["GODOT4", "Godot 4", ""],
-        ["AFRAME", "AFRAME", ""],
-        ["BABYLON", "Babylon.js", ""],
-        ["PLAYCANVAS", "PlayCanvas", ""]
-      ],
-      "default": "NONE"
-    },
-    "engine_settings": {
-      "oneOf": [
-        {"engine_val": "JANUSXR", "$ref": "#/$defs/janus", "title": "JanusXR"},
-        {"engine_val": "THREEJS", "$ref": "#/$defs/three", "title": "THREE.js"},
-        {"engine_val": "GODOT3", "$ref": "#/$defs/godot3", "title": "Godot3 (beta)"},
-        {"engine_val": "GODOT4", "$ref": "#/$defs/godot4", "title": "Godot4 (beta)"},
-        {"engine_val": "AFRAME", "$ref": "#/$defs/aframe", "title": "AFRAME (beta)"},
-        {"engine_val": "BABYLON", "$ref": "#/$defs/babylon", "title": "Babylon.js (beta)"},
-        {"engine_val": "PLAYCANVAS", "$ref": "#/$defs/playcanvas", "title": "PlayCanvas (beta)"}
-      ]
-    }
-  },
-
-  "$defs": {
-
-
-    "three": {
-      "oneOf":[
-        {"$ref": "#/$defs/three_material"},
-        {"$ref": "#/$defs/three_object"}
-      ]
-    }, 
-
-    "aframe": {
-      "oneOf":[
-        {"$ref": "#/$defs/three_material"},
-        {"$ref": "#/$defs/three_object"}
-      ]
-    }, 
-
-    "three_material":{
-      "title": "Material",
-      "description": "Material is THREE's abstract base material class",
-      "url": "https://threejs.org/docs/?q=material#Material",            
-      "properties":{
-        "_three-type": { "title": "type", "type": "string", "default":"material", "description": "needed for blender UI"},
-        "-three-material.blending":{
-          "type":"string", 
-          "enum": ["THREE.NormalBlending", "THREE.NoBlending", "THREE.AdditiveBlending", "THREE.SubtractiveBlending", "THREE.MultiplyBlending" ]
-        },
-        "-three-material.sides":{
-          "type":"string",
-          "description": "culling: which sides to render (less increases fps)",
-          "enum": ["THREE.FrontSide","THREE.BackSide","THREE.DoubleSide"]
-        },
-        "-three-material.map.offset.x+":{
-          "type":"number",
-          "description": "texture scrolling speed",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        },
-        "-three-material.map.offset.yx+":{
-          "type":"number",
-          "description": "texture scrolling speed",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        }
-      }
-    },
-
-    "three_object":{
-      "title": "Object3D",
-      "description": "Object3D is THREE's abstract base entity class",
-      "url": "https://threejs.org/docs/?q=Object3D#Object3D",
-      "properties":{
-        "_three-type": { "title": "type", "type": "string", "default":"object3D", "description": "needed for blender UI"},
-        "-three-renderOrder":{
-          "type":"integer", 
-          "minimum": 0,
-          "maximum": 100 
-        }                
-      }
-    },        
-
-    "janus": {
-      "oneOf":[
-        {"$ref": "#/$defs/janus_image"},
-        {"$ref": "#/$defs/janus_video"},
-        {"$ref": "#/$defs/janus_link"}
-      ]
-    },
-
-    "janus_image": {
-      "description": "The <image> tag allows displaying images via url, relative file, or data-uri's",
-      "url": "https://janusvr.com/docs/build/roomtag/index.html#Link",          
-      "title": "<image>",
-      "properties": {
-        "-janus-tag": {"type":"string", "default":"image"},
-        "-janus-id":  {"type":"object.name"},
-        "-janus-col": {"$ref": "#/$defs/-janus-col"},
-        "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
-        "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
-        "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
-        "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
-        "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
-        "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"}        
-      }
-    },
-    "janus_video": {
-      "title": "<video>",
-      "description": "The <video> tag allows displaying videos",
-      "url": "https://janusvr.com/docs/build/roomtag/index.html#Video",             
-      "properties": {
-        "-janus-tag": {"type":"string", "default":"video"},
-        "-janus-id":  {"type":"object.name"},
-        "-janus-thumb_id":  {"$ref": "#/$defs/-janus-thumb_id"},
-        "-janus-col": {"$ref": "#/$defs/-janus-col"},
-        "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
-        "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
-        "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
-        "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
-        "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
-        "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"},
-        "-janus-gain": { "type":"float", "minimum":0, "maximum":1 }
-      }
-    },
-    "janus_link": {
-      "title": "<link>",
-      "description": "The <link> tag allows creating portals to other scenes",
-      "url": "https://janusvr.com/docs/build/roomtag/index.html#Link",              
-      "properties": {
-        "-janus-tag": {"type":"string", "default":"link"},
-        "-janus-url":  {"type":"string", "default": "https://..."},
-        "-janus-title": {"type":"string", "default": "my title"},
-        "-janus-thumb_id":  {"$ref": "#/$defs/-janus-thumb_id"},
-        "-janus-draw_glow": {"type": "boolean", "default": True },
-        "-janus-draw_text": {"type": "boolean", "default": True },
-        "-janus-auto_load": {"type": "boolean", "default": False },
-        "-janus-mirror":    {"type": "boolean", "default": False },
-        "-janus-col": {"$ref": "#/$defs/-janus-col"},
-        "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
-        "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
-        "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
-        "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
-        "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
-        "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"}
-      }
-    },
-    "janus_object": {
-      "title": "<object>",
-      "description": "The <object> tag allows displaying 3D files",
-      "url": "https://janusvr.com/docs/build/roomtag/index.html#Object",  
-      "properties": {
-        "-janus-tag": {"type":"string", "default":"object"},
-        "-janus-col": {"$ref": "#/$defs/-janus-col"},
-        "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
-        "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
-        "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
-        "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
-        "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
-        "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"}
-      }
-    },       
-
-    "-janus-thumb_id": {"type":"object.name"},
-    "-janus-lighting": {"type": "boolean", "default": False },
-    "-janus-col":      {"type": "color", "default": "#FFFFFF"},
-    "-janus-fwd":      {"type": "string", "default": "0 0 1"},
-    "-janus-scale":    {"type": "string", "default": "1 1 1"},
-    "-janus-rotation": {"type": "string", "default": "0 0 0"},
-    "-janus-locked":   {"type": "boolean", "default": False},
-    "-janus-draw_layer":   {"type": "integer", "default": 0, "minimum":0, "maximum": 100},   
-
-    "godot3": {
-      "oneOf": [
-        { "$ref": "#/$defs/godot3_material" },
-        { "$ref": "#/$defs/godot3_spatial" }
-      ]
-    },
-
-    "godot3_material": {
-      "title": "SpatialMaterial",
-      "description": "The default Pmaterial for Godot 3.",
-      "url": "https://docs.godotengine.org/en/3.0/tutorials/3d/spatial_material.html",            
-      "properties": {
-        "_godot3-type": { 
-          "title": "type", 
-          "type": "string", 
-          "default": "SpatialMaterial"
-        },
-        "-godot3-params_blend_mode": {
-          "type": "string",
-          "description": "mat.params_blend_mode = SpatialMaterial.BLEND_MODE_MIX",
-          "enum": [
-            "SpatialMaterial.BLEND_MODE_MIX", 
-            "SpatialMaterial.BLEND_MODE_ADD", 
-            "SpatialMaterial.BLEND_MODE_SUB", 
-            "SpatialMaterial.BLEND_MODE_MUL"
+      "three": {
+        "oneOf":[
+          {"$ref": "#/$defs/three_material"},
+          {"$ref": "#/$defs/three_object"}
           ]
-        },
-        "-godot3-params_cull_mode": {
-          "type": "string",
-          "description": "mat.params_cull_mode = SpatialMaterial.CULL_BACK",
-          "enum": [
-            "SpatialMaterial.CULL_BACK", 
-            "SpatialMaterial.CULL_FRONT", 
-            "SpatialMaterial.CULL_DISABLED"
-          ]
-        },
-        "-godot3-uv1_offset.x+": {
-          "type": "number",
-          "description": "mat.uv1_offset.x += speed * delta",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        },
-        "-godot3-uv1_offset.y+": {
-          "type": "number",
-          "description": "mat.uv1_offset.y += speed * delta",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        }
-      }
-    },
+        }, 
 
-    "godot3_spatial": {
-      "title": "Object",
-      "properties": {
-        "_godot3-type": { 
-          "title": "type", 
-          "type": "string", 
-          "default": "Object"
-        },
-        "-godot3-render_priority": {
-          "type": "integer",
-          "description": "mat.render_priority = value",
-          "minimum": -128,
-          "maximum": 127
-        }
-      }
-    },
-
-    "godot4": {
-      "oneOf": [ { "$ref": "#/$defs/godot4_material" },  { "$ref": "#/$defs/godot4_node3d" } ]
-    },
-    "godot4_material": {
-      "title": "StandardMaterial3D",
-      "description": "The default PBR material for Godot 4.",
-      "url": "https://docs.godotengine.org/en/stable/classes/class_standardmaterial3d.html",
-      "properties": {
-        "_godot4-type": {
-          "title": "type",
-          "type": "string",
-          "default": "StandardMaterial3D"
-        },
-        "-gotod4-blend_mode": {
-          "type": "string",
-          "description": "mat.blend_mode = BaseMaterial3D.BLEND_MODE_MIX",
-          "enum": [
-            "BaseMaterial3D.BLEND_MODE_MIX",
-            "BaseMaterial3D.BLEND_MODE_ADD",
-            "BaseMaterial3D.BLEND_MODE_SUB",
-            "BaseMaterial3D.BLEND_MODE_MUL"
+      "aframe": {
+        "oneOf":[
+          {"$ref": "#/$defs/three_material"},
+          {"$ref": "#/$defs/three_object"}    
           ]
-        },
-        "-gotod4-cull_mode": {
-          "type": "string",
-          "description": "mat.cull_mode = BaseMaterial3D.CULL_BACK",
-          "enum": [
-            "BaseMaterial3D.CULL_BACK",
-            "BaseMaterial3D.CULL_FRONT",
-            "BaseMaterial3D.CULL_DISABLED"
-          ]
-        },
-        "-gotod4-uv1_offset.x+": {
-          "type": "number",
-          "description": "mat.uv1_offset.x += speed * delta",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        },
-        "-gotod4-uv1_offset.y+": {
-          "type": "number",
-          "description": "mat.uv1_offset.y += speed * delta",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        }
-      }
-    },
-    "godot4_node3d": {
-      "title": "Node3D",
-      "properties": {
-        "_godot4-type": {
-          "title": "type",
-          "type": "string",
-          "default": "Node3D"
-        },
-        "-godot4-render_priority": {
-          "type": "integer",
-          "description": "mat.render_priority = value",
-          "minimum": -128,
-          "maximum": 127
-        }
-      }
-    }, 
+        }, 
 
-    "playcanvas": {
-      "oneOf": [
-        {
-          "$ref": "#/$defs/playcanvas_material"
+      "three_material":{
+        "title": "Material",
+        "description": "Material is THREE's abstract base material class",
+        "url": "https://threejs.org/docs/?q=material#Material",            
+        "properties":{
+          "_three-type": { "title": "type", "type": "string", "default":"material", "description": "needed for blender UI"},
+          "-three-material.blending":{
+            "type":"string", 
+            "enum": ["THREE.NormalBlending", "THREE.NoBlending", "THREE.AdditiveBlending", "THREE.SubtractiveBlending", "THREE.MultiplyBlending" ] 
+            },
+          "-three-material.sides":{
+            "type":"string",
+            "description": "culling: which sides to render (less increases fps)",
+            "enum": ["THREE.FrontSide","THREE.BackSide","THREE.DoubleSide"]
+            },
+          "-three-material.map.offset.x+":{
+            "type":"number",
+            "description": "texture scrolling speed",
+            "default": 0.005,
+            "minimum": 0.000001,
+            "maximum": 1
+            },
+          "-three-material.map.offset.yx+":{
+            "type":"number",
+            "description": "texture scrolling speed",
+            "default": 0.005,
+            "minimum": 0.000001,
+            "maximum": 1
+            }                    
+          }
         },
-        {
-          "$ref": "#/$defs/playcanvas_entity"
-        }
-      ]
-    },
-    "playcanvas_material": {
-      "title": "StandardMaterial",
-      "properties": {
-        "_playcanvas-type": {
-          "title": "type",
-          "type": "string",
-          "default": "material",
-          "description": "var mat = new pc.StandardMaterial()"
-        },
-        "-playcanvas-material.blendType": {
-          "type": "string",
-          "description": "mat.blendType = pc.BLEND_NORMAL",
-          "enum": [
-            "pc.BLEND_NORMAL",
-            "pc.BLEND_NONE",
-            "pc.BLEND_ADDITIVE",
-            "pc.BLEND_SUBTRACTIVE",
-            "pc.BLEND_MULTIPLICATIVE"
-          ]
-        },
-        "-playcanvas-material.cull": {
-          "type": "string",
-          "description": "mat.cull = pc.CULL_BACK",
-          "enum": [
-            "pc.CULL_BACK",
-            "pc.CULL_FRONT",
-            "pc.CULL_NONE"
-          ]
-        },
-        "-playcanvas-material.diffuseMapOffset.x": {
-          "type": "number",
-          "description": "mat.diffuseMapOffset.x += speed * dt",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        },
-        "-playcanvas-material.diffuseMapOffset.y": {
-          "type": "number",
-          "description": "mat.diffuseMapOffset.y += speed * dt",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        }
-      }
-    },
 
-    "playcanvas_entity": {
-      "title": "Entity",
-      "properties": {
-        "_playcanvas-type": {
-          "title": "type",
-          "type": "string",
-          "default": "entity"
-        },
-        "-playcanvas-renderOrder": {
-          "type": "integer",
-          "description": "entity.render.layers = [layerID] // Custom sorting via layers or drawOrder",
-          "minimum": 0,
-          "maximum": 100
-        }
-      }
-    },      
+      "three_object":{
+          "title": "Object3D",
+          "description": "Object3D is THREE's abstract base entity class",
+          "url": "https://threejs.org/docs/?q=Object3D#Object3D",
+          "properties":{
+            "_three-type": { "title": "type", "type": "string", "default":"object3D", "description": "needed for blender UI"},
+            "-three-renderOrder":{
+              "type":"integer", 
+              "minimum": 0,
+              "maximum": 100 
+              }                
+            }
+          },        
+
+      "janus": {
+          "oneOf":[
+            {"$ref": "#/$defs/janus_image"},
+            {"$ref": "#/$defs/janus_video"},
+            {"$ref": "#/$defs/janus_link"}
+            ]
+          },
+
+      "janus_image": {
+          "description": "The <image> tag allows displaying images via url, relative file, or data-uri's",
+          "url": "https://janusvr.com/docs/build/roomtag/index.html#Link",          
+          "title": "<image>",
+          "properties": {
+            "-janus-tag": {"type":"string", "default":"image"},
+            "-janus-id":  {"type":"object.name"},
+            "-janus-col": {"$ref": "#/$defs/-janus-col"},
+            "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
+            "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
+            "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
+            "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
+            "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
+            "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"},        
+            }
+          },
+      "janus_video": {
+          "title": "<video>",
+          "description": "The <video> tag allows displaying videos",
+          "url": "https://janusvr.com/docs/build/roomtag/index.html#Video",             
+          "properties": {
+            "-janus-tag": {"type":"string", "default":"video"},
+            "-janus-id":  {"type":"object.name"},
+            "-janus-thumb_id":  {"$ref": "#/$defs/-janus-thumb_id"},
+            "-janus-col": {"$ref": "#/$defs/-janus-col"},
+            "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
+            "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
+            "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
+            "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
+            "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
+            "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"}
+            "-janus-gain": { "type":"float", "minimum":0, "maximum":1 }
+            }
+          },
+      "janus_link": {
+          "title": "<link>",
+          "description": "The <link> tag allows creating portals to other scenes",
+          "url": "https://janusvr.com/docs/build/roomtag/index.html#Link",              
+          "properties": {
+            "-janus-tag": {"type":"string", "default":"link"},
+            "-janus-url":  {"type":"string", "default": "https://..."},
+            "-janus-title": {"type":"string", "default": "my title"},
+            "-janus-thumb_id":  {"$ref": "#/$defs/-janus-thumb_id"},
+            "-janus-draw_glow": {"type": "boolean", "default": True },
+            "-janus-draw_text": {"type": "boolean", "default": True },
+            "-janus-auto_load": {"type": "boolean", "default": False },
+            "-janus-mirror":    {"type": "boolean", "default": False },
+            "-janus-col": {"$ref": "#/$defs/-janus-col"},
+            "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
+            "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
+            "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
+            "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
+            "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
+            "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"}
+            }
+          },
+      "janus_object": {
+          "title": "<object>",
+          "description": "The <object> tag allows displaying 3D files",
+          "url": "https://janusvr.com/docs/build/roomtag/index.html#Object",  
+          "properties": {
+            "-janus-tag": {"type":"string", "default":"object"},
+            "-janus-col": {"$ref": "#/$defs/-janus-col"},
+            "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
+            "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
+            "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
+            "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
+            "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
+            "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"}
+            }
+          },       
+
+      "-janus-thumb_id": {"type":"object.name"},
+        "-janus-lighting": {"type": "boolean", "default": False },
+        "-janus-col":      {"type": "color", "default": "#FFFFFF"},
+        "-janus-fwd":      {"type": "string", "default": "0 0 1"},
+        "-janus-scale":    {"type": "string", "default": "1 1 1"},
+        "-janus-rotation": {"type": "string", "default": "0 0 0"},
+        "-janus-locked":   {"type": "boolean", "default": False},
+        "-janus-draw_layer":   {"type": "integer", "default": 0, "minimum":0, "maximum": 100},   
+
+        "godot3": {
+            "oneOf": [
+              { "$ref": "#/$defs/godot3_material" },
+              { "$ref": "#/$defs/godot3_spatial" }
+              ]
+            },
+
+        "godot3_material": {
+            "title": "SpatialMaterial",
+            "description": "The default Pmaterial for Godot 3.",
+            "url": "https://docs.godotengine.org/en/3.0/tutorials/3d/spatial_material.html",            
+            "properties": {
+              "_godot3-type": { 
+                               "title": "type", 
+                               "type": "string", 
+                               "default": "SpatialMaterial"
+                               },
+              "-godot3-params_blend_mode": {
+                "type": "string",
+                "description": "mat.params_blend_mode = SpatialMaterial.BLEND_MODE_MIX",
+                "enum": [
+                  "SpatialMaterial.BLEND_MODE_MIX", 
+                  "SpatialMaterial.BLEND_MODE_ADD", 
+                  "SpatialMaterial.BLEND_MODE_SUB", 
+                  "SpatialMaterial.BLEND_MODE_MUL"
+                  ]
+                },
+              "-godot3-params_cull_mode": {
+                "type": "string",
+                "description": "mat.params_cull_mode = SpatialMaterial.CULL_BACK",
+                "enum": [
+                  "SpatialMaterial.CULL_BACK", 
+                  "SpatialMaterial.CULL_FRONT", 
+                  "SpatialMaterial.CULL_DISABLED"
+                  ]
+                },
+              "-godot3-uv1_offset.x+": {
+                "type": "number",
+                "description": "mat.uv1_offset.x += speed * delta",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                },
+              "-godot3-uv1_offset.y+": {
+                "type": "number",
+                "description": "mat.uv1_offset.y += speed * delta",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                }
+              }
+            },
+
+        "godot3_spatial": {
+            "title": "Object",
+            "properties": {
+              "_godot3-type": { 
+                               "title": "type", 
+                               "type": "string", 
+                               "default": "Object"
+                               },
+              "-godot3-render_priority": {
+                "type": "integer",
+                "description": "mat.render_priority = value",
+                "minimum": -128,
+                "maximum": 127
+                }
+              }
+            },
+
+        "godot4": {
+            "oneOf": [ { "$ref": "#/$defs/godot4_material" },  { "$ref": "#/$defs/godot4_node3d" } ]
+            },
+        "godot4_material": {
+            "title": "StandardMaterial3D",
+            "description": "The default PBR material for Godot 4.",
+            "url": "https://docs.godotengine.org/en/stable/classes/class_standardmaterial3d.html",
+            "properties": {
+              "_godot4-type": {
+                "title": "type",
+                "type": "string",
+                "default": "StandardMaterial3D"
+                },
+              "-gotod4-blend_mode": {
+                "type": "string",
+                "description": "mat.blend_mode = BaseMaterial3D.BLEND_MODE_MIX",
+                "enum": [
+                  "BaseMaterial3D.BLEND_MODE_MIX",
+                  "BaseMaterial3D.BLEND_MODE_ADD",
+                  "BaseMaterial3D.BLEND_MODE_SUB",
+                  "BaseMaterial3D.BLEND_MODE_MUL"
+                  ]
+                },
+              "-gotod4-cull_mode": {
+                "type": "string",
+                "description": "mat.cull_mode = BaseMaterial3D.CULL_BACK",
+                "enum": [
+                  "BaseMaterial3D.CULL_BACK",
+                  "BaseMaterial3D.CULL_FRONT",
+                  "BaseMaterial3D.CULL_DISABLED"
+                  ]
+                },
+              "-gotod4-uv1_offset.x+": {
+                "type": "number",
+                "description": "mat.uv1_offset.x += speed * delta",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                },
+              "-gotod4-uv1_offset.y+": {
+                "type": "number",
+                "description": "mat.uv1_offset.y += speed * delta",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                }
+              }
+            },
+        "godot4_node3d": {
+            "title": "Node3D",
+            "properties": {
+              "_godot4-type": {
+                "title": "type",
+                "type": "string",
+                "default": "Node3D"
+                },
+              "-godot4-render_priority": {
+                "type": "integer",
+                "description": "mat.render_priority = value",
+                "minimum": -128,
+                "maximum": 127
+                }
+              }
+            }, 
+
+        "playcanvas": {
+            "oneOf": [
+              {
+                "$ref": "#/$defs/playcanvas_material"
+                },
+              {
+                "$ref": "#/$defs/playcanvas_entity"
+                }
+              ]
+            },
+        "playcanvas_material": {
+            "title": "StandardMaterial",
+            "properties": {
+              "_playcanvas-type": {
+                "title": "type",
+                "type": "string",
+                "default": "material",
+                "description": "var mat = new pc.StandardMaterial()"
+                },
+              "-playcanvas-material.blendType": {
+                "type": "string",
+                "description": "mat.blendType = pc.BLEND_NORMAL",
+                "enum": [
+                  "pc.BLEND_NORMAL",
+                  "pc.BLEND_NONE",
+                  "pc.BLEND_ADDITIVE",
+                  "pc.BLEND_SUBTRACTIVE",
+                  "pc.BLEND_MULTIPLICATIVE"
+                  ]
+                },
+              "-playcanvas-material.cull": {
+                "type": "string",
+                "description": "mat.cull = pc.CULL_BACK",
+                "enum": [
+                  "pc.CULL_BACK",
+                  "pc.CULL_FRONT",
+                  "pc.CULL_NONE"
+                  ]
+                },
+              "-playcanvas-material.diffuseMapOffset.x": {
+                "type": "number",
+                "description": "mat.diffuseMapOffset.x += speed * dt",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                },
+              "-playcanvas-material.diffuseMapOffset.y": {
+                "type": "number",
+                "description": "mat.diffuseMapOffset.y += speed * dt",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                }
+              }
+            },
+
+        "playcanvas_entity": {
+            "title": "Entity",
+            "properties": {
+              "_playcanvas-type": {
+                "title": "type",
+                "type": "string",
+                "default": "entity"
+                },
+              "-playcanvas-renderOrder": {
+                "type": "integer",
+                "description": "entity.render.layers = [layerID] // Custom sorting via layers or drawOrder",
+                "minimum": 0,
+                "maximum": 100
+                }
+              }
+            },      
+
+        "babylon": {
+            "oneOf": [
+              {
+                "$ref": "#/$defs/babylon_material"
+                },
+              {
+                "$ref": "#/$defs/babylon_node"
+                }
+              ]
+            },
+        "babylon_material": {
+            "title": "StandardMaterial",
+            "properties": {
+              "_babylon-type": {
+                "title": "type",
+                "type": "string",
+                "default": "StandardMaterial"
+                },
+              "-babylon-material.alphaMode": {
+                "type": "string",
+                "description": "mat.alphaMode = BABYLON.Engine.ALPHA_COMBINE",
+                "enum": [
+                  "BABYLON.Engine.ALPHA_COMBINE",
+                  "BABYLON.Engine.ALPHA_DISABLE",
+                  "BABYLON.Engine.ALPHA_ADD",
+                  "BABYLON.Engine.ALPHA_SUBTRACT",
+                  "BABYLON.Engine.ALPHA_MULTIPLY"
+                  ]
+                },
+              "-babylon-material.sideOrientation": {
+                "type": "string",
+                "description": "mat.backFaceCulling = true // or mat.sideOrientation",
+                "enum": [
+                  "BABYLON.Material.ClockWiseSideOrientation",
+                  "BABYLON.Material.CounterClockWiseSideOrientation",
+                  "BABYLON.Material.TwoSidedLighting"
+                  ]
+                },
+              "-babylon-material.diffuseTexture.uOffset": {
+                "type": "number",
+                "description": "mat.diffuseTexture.uOffset += speed * scene.getAnimationRatio()",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                },
+              "-babylon-material.diffuseTexture.vOffset": {
+                "type": "number",
+                "description": "mat.diffuseTexture.vOffset += speed * scene.getAnimationRatio()",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                }
+              }
+            },
+        "babylon_node": {
+            "title": "AbstractMesh",
+            "properties": {
+              "_babylon-type": {
+                "title": "type",
+                "type": "string",
+                "default": "mesh",
+                "description": "var mesh = new BABYLON.Mesh('mesh', scene)"
+                },
+              "-babylon-renderingGroupId": {
+                "type": "integer",
+                "description": "mesh.renderingGroupId = value // 0 to 3 by default",
+                "minimum": 0,
+                "maximum": 100
+                }
+              }
+            }            
+
 
-    "babylon": {
-      "oneOf": [
-        {
-          "$ref": "#/$defs/babylon_material"
         },
-        {
-          "$ref": "#/$defs/babylon_node"
-        }
-      ]
-    },
-    "babylon_material": {
-      "title": "StandardMaterial",
-      "properties": {
-        "_babylon-type": {
-          "title": "type",
-          "type": "string",
-          "default": "StandardMaterial"
-        },
-        "-babylon-material.alphaMode": {
-          "type": "string",
-          "description": "mat.alphaMode = BABYLON.Engine.ALPHA_COMBINE",
-          "enum": [
-            "BABYLON.Engine.ALPHA_COMBINE",
-            "BABYLON.Engine.ALPHA_DISABLE",
-            "BABYLON.Engine.ALPHA_ADD",
-            "BABYLON.Engine.ALPHA_SUBTRACT",
-            "BABYLON.Engine.ALPHA_MULTIPLY"
-                        ]
-        },
-        "-babylon-material.sideOrientation": {
-          "type": "string",
-          "description": "mat.backFaceCulling = True // or mat.sideOrientation",
-          "enum": [
-            "BABYLON.Material.ClockWiseSideOrientation",
-            "BABYLON.Material.CounterClockWiseSideOrientation",
-            "BABYLON.Material.TwoSidedLighting"
-                        ]
-        },
-        "-babylon-material.diffuseTexture.uOffset": {
-          "type": "number",
-          "description": "mat.diffuseTexture.uOffset += speed * scene.getAnimationRatio()",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        },
-        "-babylon-material.diffuseTexture.vOffset": {
-          "type": "number",
-          "description": "mat.diffuseTexture.vOffset += speed * scene.getAnimationRatio()",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        }
-      }
-    },
-    "babylon_node": {
-      "title": "AbstractMesh",
-      "properties": {
-        "_babylon-type": {
-          "title": "type",
-          "type": "string",
-          "default": "mesh",
-          "description": "var mesh = new BABYLON.Mesh('mesh', scene)"
-        },
-        "-babylon-renderingGroupId": {
-          "type": "integer",
-          "description": "mesh.renderingGroupId = value // 0 to 3 by default",
-          "minimum": 0,
-          "maximum": 100
-        }
-      }
-    }            
-  }
+        "properties": {
+            "engine": {
+              "type": "enum",
+              "enum": [
+                ("NONE", "-- Select --", ""), 
+                ("XRF", "generic: hyperlinking", ""), 
+                ("JANUSXR", "JanusXR", ""), 
+                ("THREEJS", "Three.js", ""),
+                ("GODOT3", "Godot 3", ""),
+                ("GODOT4", "Godot 4", ""),
+                ("AFRAME", "AFRAME", ""),
+                ("BABYLON", "Babylon.js", ""),
+                ("PLAYCANVAS", "PlayCanvas", "")
+                ],
+              "default": "NONE"
+              },
+            "engine_settings": {
+              "oneOf": [
+                {"engine_val": "XRF", "$ref": "#/$defs/xrf", "title": "XR Fragment"},
+                {"engine_val": "JANUSXR", "$ref": "#/$defs/janus", "title": "JanusXR"},
+                {"engine_val": "THREEJS", "$ref": "#/$defs/three", "title": "THREE.js"},
+                {"engine_val": "GODOT3", "$ref": "#/$defs/godot3", "title": "Godot3 (beta)"},
+                {"engine_val": "GODOT4", "$ref": "#/$defs/godot4", "title": "Godot4 (beta)"},
+                {"engine_val": "AFRAME", "$ref": "#/$defs/aframe", "title": "AFRAME (beta)"},
+                {"engine_val": "BABYLON", "$ref": "#/$defs/babylon", "title": "Babylon.js (beta)"},
+                {"engine_val": "PLAYCANVAS", "$ref": "#/$defs/playcanvas", "title": "PlayCanvas (beta)"},
+                ]
+              }
+            }
 }
 
-####### JSONSchema-to-form-to-custom-properties generator
-#
-# The code below was written based on LLM-generated boilerplate.
-# I've had to rewrite every function, so at best it was a very convoluted
-# way to lookup all necessary function-names.
-# 
-# model: Gemini3 (fast)
-# prompt: write a jsonschemaform-tab-to-custom properties-tab blender script.
-#         The form should appear in a tab of Object properties, and render a 
-#         statically defined jsonschema with: oneOf, anyOf, allOf, $ref & $defs,
-#         datatypes like float,string,int,boolean, nesting, enums, default, title 
-#         (for human form-display), enumHuman (for human enum display), description,
-#         pattern, minimum, maximum,
-#         Regarding output: when clicking an apply-button, write the JSON-object to 
-#         the custom property-tab as 'JSON' with valuetype 'string'.
-#         If 'flatten' is set on the schema-root, collect all selected key/value 
-#         properties from the form, and write each key/value separately to the custom 
-#         property tab (only integer, string, boolean, float properties).
-
 # --- 2. HELPERS ---
 
 def resolve_schema_node(node, schema_root):
@@ -504,21 +496,19 @@ def resolve_schema_node(node, schema_root):
     return node
 
 def get_scene_object_items(self, context):
-    items = ["-- select janus asset --"]
-    # Use a set to ensure unique names if necessary, 
-    # but obj.name is always unique in Blender
+    items = [("NONE", "-- select target / asset --", "")]
+    if context is None:
+        return items
+    obj_list = []
     for obj in context.scene.objects:
-        items.append((obj.name, obj.name, f"Object: {obj.name}"))
-    
-    if not items:
-        return [("NONE", "No Objects Found", "")]
-    
-    # Optional: Sort alphabetically
-    items.sort(key=lambda x: x[0])
+        obj_list.append((obj.name, obj.name, f"Object: {obj.name}"))    
+    # Sort objects alphabetically by name
+    obj_list.sort(key=lambda x: x[1].lower())
+    items.extend(obj_list)
     return items
 
 def tell_if_const(p_name, p_info):
-    return  p_name.startswith("_") or (p_info.get("type") == "string" and "default" in p_info and len(p_info) == 2)
+    return (p_info.get("type") == "string" and "default" in p_info and len(p_info) == 2)
 
 def rgb_to_hex(rgb):
     """Converts linear RGB floats to sRGB Hex string."""
@@ -593,20 +583,26 @@ class OBJECT_OT_bake_schema(bpy.types.Operator):
         for p_name, p_info in properties.items():
             attr_name = f"ui_{p_name}"
             is_const = tell_if_const(p_name, p_info)
-            
-            if is_const:
-                data[p_name] = p_info["default"]
-            elif hasattr(obj, attr_name):
-                val = getattr(obj, attr_name)
-                
-                # Check if this specific property is defined as a color in the schema
-                resolved_info = resolve_schema_node(p_info, SCHEMA)
-                if resolved_info.get("type") == "color":
-                    # Convert the FloatVector (RGB) to "#RRGGBB"
-                    data[p_name] = rgb_to_hex(val)
-                else:
-                    # Handle normal strings, ints, floats, etc.
-                    data[p_name] = val
+            if not p_name.startswith("_"):
+                if is_const:
+                    data[p_name] = p_info["default"]
+                elif hasattr(obj, attr_name):
+                    val = getattr(obj, attr_name)
+                    
+                    # Check if this specific property is defined as a color in the schema
+                    resolved_info = resolve_schema_node(p_info, SCHEMA)
+                    if resolved_info.get("type") == "color":
+                        # Convert the FloatVector (RGB) to "#RRGGBB"
+                        data[p_name] = rgb_to_hex(val)
+                    else:
+                        # Handle normal strings, ints, floats, etc.
+                        data[p_name] = val
+            self.xrf_compose(data,p_name)
+    
+    # 3. compose correct XR Fragment hrefs        
+    def xrf_compose(self, data, p_name):
+        if p_name == "href":
+            data[p_name] = "#" + data[p_name]            
 
 # --- 4. PANEL ---
 
@@ -629,9 +625,11 @@ class VIEW3D_PT_json_schema_props(bpy.types.Panel):
                           if opt["engine_val"] == active_engine), None)
         
         if engine_opt:
-            box = layout.box()
+            layout.separator()
+            box = layout.column(align=True)
             resolved_node = resolve_schema_node(engine_opt, SCHEMA)
             self.draw_schema_node(box, obj, resolved_node)
+            layout.separator()
             
         layout.operator("object.bake_schema")
 
@@ -639,14 +637,15 @@ class VIEW3D_PT_json_schema_props(bpy.types.Panel):
         """Recursively renders the schema UI with support for conditional branching."""
 
         if "description" in node or "url" in node:
-            # Create a row and explicitly set alignment to LEFT
-            row = layout.row(align=True)
-            row.alignment = 'LEFT'
+            help_box = layout.column(align=True)
             if "url" in node:
-                op = row.operator("wm.url_open", text="", icon='HELP', emboss=False)
+                op = help_box.operator("wm.url_open", text="Documentation", icon='URL')
                 op.url = node["url"]
             if "description" in node:
-                row.label(text=node["description"] )
+                description_text = node["description"]
+                for line in description_text.split("\n"):
+                    help_box.label(text=line)
+            layout.separator() # Add space before properties
             layout.separator()
         
         # 1. Handle oneOf Routing
@@ -682,9 +681,9 @@ class VIEW3D_PT_json_schema_props(bpy.types.Panel):
         # 2. Draw standard properties for the current node
         properties = node.get("properties", {})
         for p_name, p_info in properties.items():
-            # Skip 'const' properties (Internal tags that shouldn't be edited)
+            # Skip underscore properties + (Internal tags that shouldn't be edited)
             is_const = tell_if_const(p_name, p_info)
-            if is_const:
+            if is_const or p_name.startswith("_"):
                 continue
 
             attr_name = f"ui_{p_name}"
@@ -701,9 +700,8 @@ class VIEW3D_PT_json_schema_props(bpy.types.Panel):
 # --- 5. REGISTRATION ---
 def register():
     # 1. Register top-level engine selector
-    enum_items = [tuple(item) for item in SCHEMA["properties"]["engine"]["enum"]]
     bpy.types.Object.engine = bpy.props.EnumProperty(
-        items=enum_items, 
+        items=SCHEMA["properties"]["engine"]["enum"], 
         default="NONE"
     )
 
@@ -810,3 +808,4 @@ def register():
 
 if __name__ == "__main__":
     register()
+
diff --git a/schema/xrfragment-engine-prefixes.json b/schema/xrfragment-engine-prefixes.json
index c2fbd1a..4b8b961 100644
--- a/schema/xrfragment-engine-prefixes.json
+++ b/schema/xrfragment-engine-prefixes.json
@@ -1,469 +1,481 @@
 {
-  "$schema": "https://json-schema.org/draft/2020-12/schema",  
-  "$id": "https://xrfragment.org/schema/xrfragment-engine-prefixes.json",
-  "$version": 34,
-  "title": "XR Fragments Engine Prefixes",
-  "type": "object",
-  "flatten": true,
+    "title": "XR Fragments",
+    "type": "object",
+"$version": 3,
+    "flatten": true,
+    "$defs": {
 
-  "properties": {
-    "engine": {
-      "type": "enum",
-      "enum": [
-        ["NONE", "-- Select --", ""], 
-        ["JANUSXR", "JanusXR", ""], 
-        ["THREEJS", "Three.js", ""],
-        ["GODOT3", "Godot 3", ""],
-        ["GODOT4", "Godot 4", ""],
-        ["AFRAME", "AFRAME", ""],
-        ["BABYLON", "Babylon.js", ""],
-        ["PLAYCANVAS", "PlayCanvas", ""]
-      ],
-      "default": "NONE"
-    },
-    "engine_settings": {
-      "oneOf": [
-        {"engine_val": "JANUSXR", "$ref": "#/$defs/janus", "title": "JanusXR"},
-        {"engine_val": "THREEJS", "$ref": "#/$defs/three", "title": "THREE.js"},
-        {"engine_val": "GODOT3", "$ref": "#/$defs/godot3", "title": "Godot3 (beta)"},
-        {"engine_val": "GODOT4", "$ref": "#/$defs/godot4", "title": "Godot4 (beta)"},
-        {"engine_val": "AFRAME", "$ref": "#/$defs/aframe", "title": "AFRAME (beta)"},
-        {"engine_val": "BABYLON", "$ref": "#/$defs/babylon", "title": "Babylon.js (beta)"},
-        {"engine_val": "PLAYCANVAS", "$ref": "#/$defs/playcanvas", "title": "PlayCanvas (beta)"}
-      ]
-    }
-  },
+      "xrf":{
+        "title": "XR Fragments",
+        "description": "XR Fragments (level2) promotes embedding clickable hyperlinks\nin 3D files (via the href attribute).\nMake sure to check 'custom attributes' in your export dialog.",
+        "url": "https://xrfragment.org/#How%20it%20works",            
+        "properties":{
+          "_xrf-type": { "title": "type", "type": "string", "default":"xrf", "description": "needed for blender UI"},
+          "href":{
+            "type":"object.name",
+            "description": "teleport to / href"
+            }           
+          }
+        },   
 
-  "$defs": {
-
-
-    "three": {
-      "oneOf":[
-        {"$ref": "#/$defs/three_material"},
-        {"$ref": "#/$defs/three_object"}
-      ]
-    }, 
-
-    "aframe": {
-      "oneOf":[
-        {"$ref": "#/$defs/three_material"},
-        {"$ref": "#/$defs/three_object"}
-      ]
-    }, 
-
-    "three_material":{
-      "title": "Material",
-      "description": "Material is THREE's abstract base material class",
-      "url": "https://threejs.org/docs/?q=material#Material",            
-      "properties":{
-        "_three-type": { "title": "type", "type": "string", "default":"material", "description": "needed for blender UI"},
-        "-three-material.blending":{
-          "type":"string", 
-          "enum": ["THREE.NormalBlending", "THREE.NoBlending", "THREE.AdditiveBlending", "THREE.SubtractiveBlending", "THREE.MultiplyBlending" ]
-        },
-        "-three-material.sides":{
-          "type":"string",
-          "description": "culling: which sides to render (less increases fps)",
-          "enum": ["THREE.FrontSide","THREE.BackSide","THREE.DoubleSide"]
-        },
-        "-three-material.map.offset.x+":{
-          "type":"number",
-          "description": "texture scrolling speed",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        },
-        "-three-material.map.offset.yx+":{
-          "type":"number",
-          "description": "texture scrolling speed",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        }
-      }
-    },
-
-    "three_object":{
-      "title": "Object3D",
-      "description": "Object3D is THREE's abstract base entity class",
-      "url": "https://threejs.org/docs/?q=Object3D#Object3D",
-      "properties":{
-        "_three-type": { "title": "type", "type": "string", "default":"object3D", "description": "needed for blender UI"},
-        "-three-renderOrder":{
-          "type":"integer", 
-          "minimum": 0,
-          "maximum": 100 
-        }                
-      }
-    },        
-
-    "janus": {
-      "oneOf":[
-        {"$ref": "#/$defs/janus_image"},
-        {"$ref": "#/$defs/janus_video"},
-        {"$ref": "#/$defs/janus_link"}
-      ]
-    },
-
-    "janus_image": {
-      "description": "The <image> tag allows displaying images via url, relative file, or data-uri's",
-      "url": "https://janusvr.com/docs/build/roomtag/index.html#Link",          
-      "title": "<image>",
-      "properties": {
-        "-janus-tag": {"type":"string", "default":"image"},
-        "-janus-id":  {"type":"object.name"},
-        "-janus-col": {"$ref": "#/$defs/-janus-col"},
-        "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
-        "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
-        "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
-        "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
-        "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
-        "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"}        
-      }
-    },
-    "janus_video": {
-      "title": "<video>",
-      "description": "The <video> tag allows displaying videos",
-      "url": "https://janusvr.com/docs/build/roomtag/index.html#Video",             
-      "properties": {
-        "-janus-tag": {"type":"string", "default":"video"},
-        "-janus-id":  {"type":"object.name"},
-        "-janus-thumb_id":  {"$ref": "#/$defs/-janus-thumb_id"},
-        "-janus-col": {"$ref": "#/$defs/-janus-col"},
-        "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
-        "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
-        "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
-        "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
-        "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
-        "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"},
-        "-janus-gain": { "type":"float", "minimum":0, "maximum":1 }
-      }
-    },
-    "janus_link": {
-      "title": "<link>",
-      "description": "The <link> tag allows creating portals to other scenes",
-      "url": "https://janusvr.com/docs/build/roomtag/index.html#Link",              
-      "properties": {
-        "-janus-tag": {"type":"string", "default":"link"},
-        "-janus-url":  {"type":"string", "default": "https://..."},
-        "-janus-title": {"type":"string", "default": "my title"},
-        "-janus-thumb_id":  {"$ref": "#/$defs/-janus-thumb_id"},
-        "-janus-draw_glow": {"type": "boolean", "default": true },
-        "-janus-draw_text": {"type": "boolean", "default": true },
-        "-janus-auto_load": {"type": "boolean", "default": false },
-        "-janus-mirror":    {"type": "boolean", "default": false },
-        "-janus-col": {"$ref": "#/$defs/-janus-col"},
-        "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
-        "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
-        "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
-        "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
-        "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
-        "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"}
-      }
-    },
-    "janus_object": {
-      "title": "<object>",
-      "description": "The <object> tag allows displaying 3D files",
-      "url": "https://janusvr.com/docs/build/roomtag/index.html#Object",  
-      "properties": {
-        "-janus-tag": {"type":"string", "default":"object"},
-        "-janus-col": {"$ref": "#/$defs/-janus-col"},
-        "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
-        "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
-        "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
-        "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
-        "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
-        "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"}
-      }
-    },       
-
-    "-janus-thumb_id": {"type":"object.name"},
-    "-janus-lighting": {"type": "boolean", "default": false },
-    "-janus-col":      {"type": "color", "default": "#FFFFFF"},
-    "-janus-fwd":      {"type": "string", "default": "0 0 1"},
-    "-janus-scale":    {"type": "string", "default": "1 1 1"},
-    "-janus-rotation": {"type": "string", "default": "0 0 0"},
-    "-janus-locked":   {"type": "boolean", "default": false},
-    "-janus-draw_layer":   {"type": "integer", "default": 0, "minimum":0, "maximum": 100},   
-
-    "godot3": {
-      "oneOf": [
-        { "$ref": "#/$defs/godot3_material" },
-        { "$ref": "#/$defs/godot3_spatial" }
-      ]
-    },
-
-    "godot3_material": {
-      "title": "SpatialMaterial",
-      "description": "The default Pmaterial for Godot 3.",
-      "url": "https://docs.godotengine.org/en/3.0/tutorials/3d/spatial_material.html",            
-      "properties": {
-        "_godot3-type": { 
-          "title": "type", 
-          "type": "string", 
-          "default": "SpatialMaterial"
-        },
-        "-godot3-params_blend_mode": {
-          "type": "string",
-          "description": "mat.params_blend_mode = SpatialMaterial.BLEND_MODE_MIX",
-          "enum": [
-            "SpatialMaterial.BLEND_MODE_MIX", 
-            "SpatialMaterial.BLEND_MODE_ADD", 
-            "SpatialMaterial.BLEND_MODE_SUB", 
-            "SpatialMaterial.BLEND_MODE_MUL"
+      "three": {
+        "oneOf":[
+          {"$ref": "#/$defs/three_material"},
+          {"$ref": "#/$defs/three_object"}
           ]
-        },
-        "-godot3-params_cull_mode": {
-          "type": "string",
-          "description": "mat.params_cull_mode = SpatialMaterial.CULL_BACK",
-          "enum": [
-            "SpatialMaterial.CULL_BACK", 
-            "SpatialMaterial.CULL_FRONT", 
-            "SpatialMaterial.CULL_DISABLED"
-          ]
-        },
-        "-godot3-uv1_offset.x+": {
-          "type": "number",
-          "description": "mat.uv1_offset.x += speed * delta",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        },
-        "-godot3-uv1_offset.y+": {
-          "type": "number",
-          "description": "mat.uv1_offset.y += speed * delta",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        }
-      }
-    },
+        }, 
 
-    "godot3_spatial": {
-      "title": "Object",
-      "properties": {
-        "_godot3-type": { 
-          "title": "type", 
-          "type": "string", 
-          "default": "Object"
-        },
-        "-godot3-render_priority": {
-          "type": "integer",
-          "description": "mat.render_priority = value",
-          "minimum": -128,
-          "maximum": 127
-        }
-      }
-    },
-
-    "godot4": {
-      "oneOf": [ { "$ref": "#/$defs/godot4_material" },  { "$ref": "#/$defs/godot4_node3d" } ]
-    },
-    "godot4_material": {
-      "title": "StandardMaterial3D",
-      "description": "The default PBR material for Godot 4.",
-      "url": "https://docs.godotengine.org/en/stable/classes/class_standardmaterial3d.html",
-      "properties": {
-        "_godot4-type": {
-          "title": "type",
-          "type": "string",
-          "default": "StandardMaterial3D"
-        },
-        "-gotod4-blend_mode": {
-          "type": "string",
-          "description": "mat.blend_mode = BaseMaterial3D.BLEND_MODE_MIX",
-          "enum": [
-            "BaseMaterial3D.BLEND_MODE_MIX",
-            "BaseMaterial3D.BLEND_MODE_ADD",
-            "BaseMaterial3D.BLEND_MODE_SUB",
-            "BaseMaterial3D.BLEND_MODE_MUL"
+      "aframe": {
+        "oneOf":[
+          {"$ref": "#/$defs/three_material"},
+          {"$ref": "#/$defs/three_object"}    
           ]
-        },
-        "-gotod4-cull_mode": {
-          "type": "string",
-          "description": "mat.cull_mode = BaseMaterial3D.CULL_BACK",
-          "enum": [
-            "BaseMaterial3D.CULL_BACK",
-            "BaseMaterial3D.CULL_FRONT",
-            "BaseMaterial3D.CULL_DISABLED"
-          ]
-        },
-        "-gotod4-uv1_offset.x+": {
-          "type": "number",
-          "description": "mat.uv1_offset.x += speed * delta",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        },
-        "-gotod4-uv1_offset.y+": {
-          "type": "number",
-          "description": "mat.uv1_offset.y += speed * delta",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        }
-      }
-    },
-    "godot4_node3d": {
-      "title": "Node3D",
-      "properties": {
-        "_godot4-type": {
-          "title": "type",
-          "type": "string",
-          "default": "Node3D"
-        },
-        "-godot4-render_priority": {
-          "type": "integer",
-          "description": "mat.render_priority = value",
-          "minimum": -128,
-          "maximum": 127
-        }
-      }
-    }, 
+        }, 
 
-    "playcanvas": {
-      "oneOf": [
-        {
-          "$ref": "#/$defs/playcanvas_material"
+      "three_material":{
+        "title": "Material",
+        "description": "Material is THREE's abstract base material class",
+        "url": "https://threejs.org/docs/?q=material#Material",            
+        "properties":{
+          "_three-type": { "title": "type", "type": "string", "default":"material", "description": "needed for blender UI"},
+          "-three-material.blending":{
+            "type":"string", 
+            "enum": ["THREE.NormalBlending", "THREE.NoBlending", "THREE.AdditiveBlending", "THREE.SubtractiveBlending", "THREE.MultiplyBlending" ] 
+            },
+          "-three-material.sides":{
+            "type":"string",
+            "description": "culling: which sides to render (less increases fps)",
+            "enum": ["THREE.FrontSide","THREE.BackSide","THREE.DoubleSide"]
+            },
+          "-three-material.map.offset.x+":{
+            "type":"number",
+            "description": "texture scrolling speed",
+            "default": 0.005,
+            "minimum": 0.000001,
+            "maximum": 1
+            },
+          "-three-material.map.offset.yx+":{
+            "type":"number",
+            "description": "texture scrolling speed",
+            "default": 0.005,
+            "minimum": 0.000001,
+            "maximum": 1
+            }                    
+          }
         },
-        {
-          "$ref": "#/$defs/playcanvas_entity"
-        }
-      ]
-    },
-    "playcanvas_material": {
-      "title": "StandardMaterial",
-      "properties": {
-        "_playcanvas-type": {
-          "title": "type",
-          "type": "string",
-          "default": "material",
-          "description": "var mat = new pc.StandardMaterial()"
-        },
-        "-playcanvas-material.blendType": {
-          "type": "string",
-          "description": "mat.blendType = pc.BLEND_NORMAL",
-          "enum": [
-            "pc.BLEND_NORMAL",
-            "pc.BLEND_NONE",
-            "pc.BLEND_ADDITIVE",
-            "pc.BLEND_SUBTRACTIVE",
-            "pc.BLEND_MULTIPLICATIVE"
-          ]
-        },
-        "-playcanvas-material.cull": {
-          "type": "string",
-          "description": "mat.cull = pc.CULL_BACK",
-          "enum": [
-            "pc.CULL_BACK",
-            "pc.CULL_FRONT",
-            "pc.CULL_NONE"
-          ]
-        },
-        "-playcanvas-material.diffuseMapOffset.x": {
-          "type": "number",
-          "description": "mat.diffuseMapOffset.x += speed * dt",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        },
-        "-playcanvas-material.diffuseMapOffset.y": {
-          "type": "number",
-          "description": "mat.diffuseMapOffset.y += speed * dt",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        }
-      }
-    },
 
-    "playcanvas_entity": {
-      "title": "Entity",
-      "properties": {
-        "_playcanvas-type": {
-          "title": "type",
-          "type": "string",
-          "default": "entity"
-        },
-        "-playcanvas-renderOrder": {
-          "type": "integer",
-          "description": "entity.render.layers = [layerID] // Custom sorting via layers or drawOrder",
-          "minimum": 0,
-          "maximum": 100
-        }
-      }
-    },      
+      "three_object":{
+          "title": "Object3D",
+          "description": "Object3D is THREE's abstract base entity class",
+          "url": "https://threejs.org/docs/?q=Object3D#Object3D",
+          "properties":{
+            "_three-type": { "title": "type", "type": "string", "default":"object3D", "description": "needed for blender UI"},
+            "-three-renderOrder":{
+              "type":"integer", 
+              "minimum": 0,
+              "maximum": 100 
+              }                
+            }
+          },        
+
+      "janus": {
+          "oneOf":[
+            {"$ref": "#/$defs/janus_image"},
+            {"$ref": "#/$defs/janus_video"},
+            {"$ref": "#/$defs/janus_link"}
+            ]
+          },
+
+      "janus_image": {
+          "description": "The <image> tag allows displaying images via url, relative file, or data-uri's",
+          "url": "https://janusvr.com/docs/build/roomtag/index.html#Link",          
+          "title": "<image>",
+          "properties": {
+            "-janus-tag": {"type":"string", "default":"image"},
+            "-janus-id":  {"type":"object.name"},
+            "-janus-col": {"$ref": "#/$defs/-janus-col"},
+            "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
+            "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
+            "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
+            "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
+            "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
+            "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"},        
+            }
+          },
+      "janus_video": {
+          "title": "<video>",
+          "description": "The <video> tag allows displaying videos",
+          "url": "https://janusvr.com/docs/build/roomtag/index.html#Video",             
+          "properties": {
+            "-janus-tag": {"type":"string", "default":"video"},
+            "-janus-id":  {"type":"object.name"},
+            "-janus-thumb_id":  {"$ref": "#/$defs/-janus-thumb_id"},
+            "-janus-col": {"$ref": "#/$defs/-janus-col"},
+            "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
+            "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
+            "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
+            "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
+            "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
+            "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"}
+            "-janus-gain": { "type":"float", "minimum":0, "maximum":1 }
+            }
+          },
+      "janus_link": {
+          "title": "<link>",
+          "description": "The <link> tag allows creating portals to other scenes",
+          "url": "https://janusvr.com/docs/build/roomtag/index.html#Link",              
+          "properties": {
+            "-janus-tag": {"type":"string", "default":"link"},
+            "-janus-url":  {"type":"string", "default": "https://..."},
+            "-janus-title": {"type":"string", "default": "my title"},
+            "-janus-thumb_id":  {"$ref": "#/$defs/-janus-thumb_id"},
+            "-janus-draw_glow": {"type": "boolean", "default": true },
+            "-janus-draw_text": {"type": "boolean", "default": true },
+            "-janus-auto_load": {"type": "boolean", "default": false },
+            "-janus-mirror":    {"type": "boolean", "default": false },
+            "-janus-col": {"$ref": "#/$defs/-janus-col"},
+            "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
+            "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
+            "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
+            "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
+            "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
+            "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"}
+            }
+          },
+      "janus_object": {
+          "title": "<object>",
+          "description": "The <object> tag allows displaying 3D files",
+          "url": "https://janusvr.com/docs/build/roomtag/index.html#Object",  
+          "properties": {
+            "-janus-tag": {"type":"string", "default":"object"},
+            "-janus-col": {"$ref": "#/$defs/-janus-col"},
+            "-janus-fwd":   {"$ref": "#/$defs/-janus-fwd"},
+            "-janus-scale":  {"$ref": "#/$defs/-janus-scale"},
+            "-janus-rotation":  {"$ref": "#/$defs/-janus-rotation" },
+            "-janus-locked": {"$ref": "#/$defs/-janus-locked"},
+            "-janus-lighting": {"$ref": "#/$defs/-janus-lighting"},
+            "-janus-draw-layer":   {"$ref": "#/$defs/-janus-draw_layer"}
+            }
+          },       
+
+      "-janus-thumb_id": {"type":"object.name"},
+        "-janus-lighting": {"type": "boolean", "default": false },
+        "-janus-col":      {"type": "color", "default": "#FFFFFF"},
+        "-janus-fwd":      {"type": "string", "default": "0 0 1"},
+        "-janus-scale":    {"type": "string", "default": "1 1 1"},
+        "-janus-rotation": {"type": "string", "default": "0 0 0"},
+        "-janus-locked":   {"type": "boolean", "default": false},
+        "-janus-draw_layer":   {"type": "integer", "default": 0, "minimum":0, "maximum": 100},   
+
+        "godot3": {
+            "oneOf": [
+              { "$ref": "#/$defs/godot3_material" },
+              { "$ref": "#/$defs/godot3_spatial" }
+              ]
+            },
+
+        "godot3_material": {
+            "title": "SpatialMaterial",
+            "description": "The default Pmaterial for Godot 3.",
+            "url": "https://docs.godotengine.org/en/3.0/tutorials/3d/spatial_material.html",            
+            "properties": {
+              "_godot3-type": { 
+                               "title": "type", 
+                               "type": "string", 
+                               "default": "SpatialMaterial"
+                               },
+              "-godot3-params_blend_mode": {
+                "type": "string",
+                "description": "mat.params_blend_mode = SpatialMaterial.BLEND_MODE_MIX",
+                "enum": [
+                  "SpatialMaterial.BLEND_MODE_MIX", 
+                  "SpatialMaterial.BLEND_MODE_ADD", 
+                  "SpatialMaterial.BLEND_MODE_SUB", 
+                  "SpatialMaterial.BLEND_MODE_MUL"
+                  ]
+                },
+              "-godot3-params_cull_mode": {
+                "type": "string",
+                "description": "mat.params_cull_mode = SpatialMaterial.CULL_BACK",
+                "enum": [
+                  "SpatialMaterial.CULL_BACK", 
+                  "SpatialMaterial.CULL_FRONT", 
+                  "SpatialMaterial.CULL_DISABLED"
+                  ]
+                },
+              "-godot3-uv1_offset.x+": {
+                "type": "number",
+                "description": "mat.uv1_offset.x += speed * delta",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                },
+              "-godot3-uv1_offset.y+": {
+                "type": "number",
+                "description": "mat.uv1_offset.y += speed * delta",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                }
+              }
+            },
+
+        "godot3_spatial": {
+            "title": "Object",
+            "properties": {
+              "_godot3-type": { 
+                               "title": "type", 
+                               "type": "string", 
+                               "default": "Object"
+                               },
+              "-godot3-render_priority": {
+                "type": "integer",
+                "description": "mat.render_priority = value",
+                "minimum": -128,
+                "maximum": 127
+                }
+              }
+            },
+
+        "godot4": {
+            "oneOf": [ { "$ref": "#/$defs/godot4_material" },  { "$ref": "#/$defs/godot4_node3d" } ]
+            },
+        "godot4_material": {
+            "title": "StandardMaterial3D",
+            "description": "The default PBR material for Godot 4.",
+            "url": "https://docs.godotengine.org/en/stable/classes/class_standardmaterial3d.html",
+            "properties": {
+              "_godot4-type": {
+                "title": "type",
+                "type": "string",
+                "default": "StandardMaterial3D"
+                },
+              "-gotod4-blend_mode": {
+                "type": "string",
+                "description": "mat.blend_mode = BaseMaterial3D.BLEND_MODE_MIX",
+                "enum": [
+                  "BaseMaterial3D.BLEND_MODE_MIX",
+                  "BaseMaterial3D.BLEND_MODE_ADD",
+                  "BaseMaterial3D.BLEND_MODE_SUB",
+                  "BaseMaterial3D.BLEND_MODE_MUL"
+                  ]
+                },
+              "-gotod4-cull_mode": {
+                "type": "string",
+                "description": "mat.cull_mode = BaseMaterial3D.CULL_BACK",
+                "enum": [
+                  "BaseMaterial3D.CULL_BACK",
+                  "BaseMaterial3D.CULL_FRONT",
+                  "BaseMaterial3D.CULL_DISABLED"
+                  ]
+                },
+              "-gotod4-uv1_offset.x+": {
+                "type": "number",
+                "description": "mat.uv1_offset.x += speed * delta",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                },
+              "-gotod4-uv1_offset.y+": {
+                "type": "number",
+                "description": "mat.uv1_offset.y += speed * delta",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                }
+              }
+            },
+        "godot4_node3d": {
+            "title": "Node3D",
+            "properties": {
+              "_godot4-type": {
+                "title": "type",
+                "type": "string",
+                "default": "Node3D"
+                },
+              "-godot4-render_priority": {
+                "type": "integer",
+                "description": "mat.render_priority = value",
+                "minimum": -128,
+                "maximum": 127
+                }
+              }
+            }, 
+
+        "playcanvas": {
+            "oneOf": [
+              {
+                "$ref": "#/$defs/playcanvas_material"
+                },
+              {
+                "$ref": "#/$defs/playcanvas_entity"
+                }
+              ]
+            },
+        "playcanvas_material": {
+            "title": "StandardMaterial",
+            "properties": {
+              "_playcanvas-type": {
+                "title": "type",
+                "type": "string",
+                "default": "material",
+                "description": "var mat = new pc.StandardMaterial()"
+                },
+              "-playcanvas-material.blendType": {
+                "type": "string",
+                "description": "mat.blendType = pc.BLEND_NORMAL",
+                "enum": [
+                  "pc.BLEND_NORMAL",
+                  "pc.BLEND_NONE",
+                  "pc.BLEND_ADDITIVE",
+                  "pc.BLEND_SUBTRACTIVE",
+                  "pc.BLEND_MULTIPLICATIVE"
+                  ]
+                },
+              "-playcanvas-material.cull": {
+                "type": "string",
+                "description": "mat.cull = pc.CULL_BACK",
+                "enum": [
+                  "pc.CULL_BACK",
+                  "pc.CULL_FRONT",
+                  "pc.CULL_NONE"
+                  ]
+                },
+              "-playcanvas-material.diffuseMapOffset.x": {
+                "type": "number",
+                "description": "mat.diffuseMapOffset.x += speed * dt",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                },
+              "-playcanvas-material.diffuseMapOffset.y": {
+                "type": "number",
+                "description": "mat.diffuseMapOffset.y += speed * dt",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                }
+              }
+            },
+
+        "playcanvas_entity": {
+            "title": "Entity",
+            "properties": {
+              "_playcanvas-type": {
+                "title": "type",
+                "type": "string",
+                "default": "entity"
+                },
+              "-playcanvas-renderOrder": {
+                "type": "integer",
+                "description": "entity.render.layers = [layerID] // Custom sorting via layers or drawOrder",
+                "minimum": 0,
+                "maximum": 100
+                }
+              }
+            },      
+
+        "babylon": {
+            "oneOf": [
+              {
+                "$ref": "#/$defs/babylon_material"
+                },
+              {
+                "$ref": "#/$defs/babylon_node"
+                }
+              ]
+            },
+        "babylon_material": {
+            "title": "StandardMaterial",
+            "properties": {
+              "_babylon-type": {
+                "title": "type",
+                "type": "string",
+                "default": "StandardMaterial"
+                },
+              "-babylon-material.alphaMode": {
+                "type": "string",
+                "description": "mat.alphaMode = BABYLON.Engine.ALPHA_COMBINE",
+                "enum": [
+                  "BABYLON.Engine.ALPHA_COMBINE",
+                  "BABYLON.Engine.ALPHA_DISABLE",
+                  "BABYLON.Engine.ALPHA_ADD",
+                  "BABYLON.Engine.ALPHA_SUBTRACT",
+                  "BABYLON.Engine.ALPHA_MULTIPLY"
+                  ]
+                },
+              "-babylon-material.sideOrientation": {
+                "type": "string",
+                "description": "mat.backFaceCulling = true // or mat.sideOrientation",
+                "enum": [
+                  "BABYLON.Material.ClockWiseSideOrientation",
+                  "BABYLON.Material.CounterClockWiseSideOrientation",
+                  "BABYLON.Material.TwoSidedLighting"
+                  ]
+                },
+              "-babylon-material.diffuseTexture.uOffset": {
+                "type": "number",
+                "description": "mat.diffuseTexture.uOffset += speed * scene.getAnimationRatio()",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                },
+              "-babylon-material.diffuseTexture.vOffset": {
+                "type": "number",
+                "description": "mat.diffuseTexture.vOffset += speed * scene.getAnimationRatio()",
+                "default": 0.005,
+                "minimum": 0.000001,
+                "maximum": 1
+                }
+              }
+            },
+        "babylon_node": {
+            "title": "AbstractMesh",
+            "properties": {
+              "_babylon-type": {
+                "title": "type",
+                "type": "string",
+                "default": "mesh",
+                "description": "var mesh = new BABYLON.Mesh('mesh', scene)"
+                },
+              "-babylon-renderingGroupId": {
+                "type": "integer",
+                "description": "mesh.renderingGroupId = value // 0 to 3 by default",
+                "minimum": 0,
+                "maximum": 100
+                }
+              }
+            }            
+
 
-    "babylon": {
-      "oneOf": [
-        {
-          "$ref": "#/$defs/babylon_material"
         },
-        {
-          "$ref": "#/$defs/babylon_node"
-        }
-      ]
-    },
-    "babylon_material": {
-      "title": "StandardMaterial",
-      "properties": {
-        "_babylon-type": {
-          "title": "type",
-          "type": "string",
-          "default": "StandardMaterial"
-        },
-        "-babylon-material.alphaMode": {
-          "type": "string",
-          "description": "mat.alphaMode = BABYLON.Engine.ALPHA_COMBINE",
-          "enum": [
-            "BABYLON.Engine.ALPHA_COMBINE",
-            "BABYLON.Engine.ALPHA_DISABLE",
-            "BABYLON.Engine.ALPHA_ADD",
-            "BABYLON.Engine.ALPHA_SUBTRACT",
-            "BABYLON.Engine.ALPHA_MULTIPLY"
-                        ]
-        },
-        "-babylon-material.sideOrientation": {
-          "type": "string",
-          "description": "mat.backFaceCulling = true // or mat.sideOrientation",
-          "enum": [
-            "BABYLON.Material.ClockWiseSideOrientation",
-            "BABYLON.Material.CounterClockWiseSideOrientation",
-            "BABYLON.Material.TwoSidedLighting"
-                        ]
-        },
-        "-babylon-material.diffuseTexture.uOffset": {
-          "type": "number",
-          "description": "mat.diffuseTexture.uOffset += speed * scene.getAnimationRatio()",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        },
-        "-babylon-material.diffuseTexture.vOffset": {
-          "type": "number",
-          "description": "mat.diffuseTexture.vOffset += speed * scene.getAnimationRatio()",
-          "default": 0.005,
-          "minimum": 0.000001,
-          "maximum": 1
-        }
-      }
-    },
-    "babylon_node": {
-      "title": "AbstractMesh",
-      "properties": {
-        "_babylon-type": {
-          "title": "type",
-          "type": "string",
-          "default": "mesh",
-          "description": "var mesh = new BABYLON.Mesh('mesh', scene)"
-        },
-        "-babylon-renderingGroupId": {
-          "type": "integer",
-          "description": "mesh.renderingGroupId = value // 0 to 3 by default",
-          "minimum": 0,
-          "maximum": 100
-        }
-      }
-    }            
-  }
+        "properties": {
+            "engine": {
+              "type": "enum",
+              "enum": [
+                ("NONE", "-- Select --", ""), 
+                ("XRF", "generic: hyperlinking", ""), 
+                ("JANUSXR", "JanusXR", ""), 
+                ("THREEJS", "Three.js", ""),
+                ("GODOT3", "Godot 3", ""),
+                ("GODOT4", "Godot 4", ""),
+                ("AFRAME", "AFRAME", ""),
+                ("BABYLON", "Babylon.js", ""),
+                ("PLAYCANVAS", "PlayCanvas", "")
+                ],
+              "default": "NONE"
+              },
+            "engine_settings": {
+              "oneOf": [
+                {"engine_val": "XRF", "$ref": "#/$defs/xrf", "title": "XR Fragment"},
+                {"engine_val": "JANUSXR", "$ref": "#/$defs/janus", "title": "JanusXR"},
+                {"engine_val": "THREEJS", "$ref": "#/$defs/three", "title": "THREE.js"},
+                {"engine_val": "GODOT3", "$ref": "#/$defs/godot3", "title": "Godot3 (beta)"},
+                {"engine_val": "GODOT4", "$ref": "#/$defs/godot4", "title": "Godot4 (beta)"},
+                {"engine_val": "AFRAME", "$ref": "#/$defs/aframe", "title": "AFRAME (beta)"},
+                {"engine_val": "BABYLON", "$ref": "#/$defs/babylon", "title": "Babylon.js (beta)"},
+                {"engine_val": "PLAYCANVAS", "$ref": "#/$defs/playcanvas", "title": "PlayCanvas (beta)"},
+                ]
+              }
+            }
 }