References

Types can reference each other in several ways, each serving a different purpose in describing relationships between assets:

Direct References

Simple references to other objects using their URLs:

{
  "@context": {
    "@vocab": "https://schema.org/",
    "mvmd": "https://mvmd.org/v1/"
  },
  "@type": "3DModel",
  "name": "Character Model",
  "image": "https://example.com/preview.jpg",
  "thumbnail": "https://example.com/thumbnail.jpg",
  "contentUrl": "https://example.com/model.glb"
}

Structured References

Full object references that include complete metadata:

{
  "@context": {
    "@vocab": "https://schema.org/",
    "mvmd": "https://mvmd.org/v1/"
  },
  "@type": "3DModel",
  "name": "Character Model",
  "image": {
    "@type": "ImageObject",
    "name": "Character Preview",
    "contentUrl": "https://example.com/preview.jpg",
    "encodingFormat": "image/jpeg",
    "width": "1024",
    "height": "1024"
  }
}

Primary Entity References

Using mainEntity to indicate the primary subject of a metadata object:

{
  "@context": {
    "@vocab": "https://schema.org/",
    "mvmd": "https://mvmd.org/v1/"
  },
  "@type": "ImageObject",
  "name": "Character Preview Image",
  "contentUrl": "https://example.com/preview.jpg",
  "mainEntity": {
    "@type": "3DModel",
    "name": "Character Model",
    "contentUrl": "https://example.com/model.glb",
    "encodingFormat": "model/gltf-binary"
  }
}

Alternative Version References

Using sameAs to link to the same asset in different locations or formats:

{
  "@context": {
    "@vocab": "https://schema.org/",
    "mvmd": "https://mvmd.org/v1/"
  },
  "@type": "3DModel",
  "name": "Character Model",
  "contentUrl": "https://example.com/model.glb",
  "sameAs": [
    "https://other-platform.com/assets/character-123",
    "ipfs://QmXaXa1XaX...",
    "ar://asset/character-123"
  ]
}

Media References

Using associatedMedia to link to related media assets:

{
  "@context": {
    "@vocab": "https://schema.org/",
    "mvmd": "https://mvmd.org/v1/"
  },
  "@type": "3DModel",
  "name": "Character Model",
  "contentUrl": "https://example.com/model.glb",
  "associatedMedia": [
    {
      "@type": "ImageObject",
      "name": "Texture Map",
      "contentUrl": "https://example.com/texture.jpg",
      "encodingFormat": "image/jpeg"
    },
    {
      "@type": "VideoObject",
      "name": "Animation Preview",
      "contentUrl": "https://example.com/preview.mp4",
      "encodingFormat": "video/mp4"
    }
  ]
}

Embedded Content References

Using encodesCreativeWork to indicate embedded or encoded content:

{
  "@context": {
    "@vocab": "https://schema.org/",
    "mvmd": "https://mvmd.org/v1/"
  },
  "@type": "3DModel",
  "name": "Interactive Kiosk",
  "contentUrl": "https://example.com/kiosk.glb",
  "encodesCreativeWork": [
    {
      "@type": "ImageObject",
      "name": "Display Content",
      "contentUrl": "https://example.com/display.jpg"
    },
    {
      "@type": "TextObject",
      "name": "Information Text",
      "contentUrl": "https://example.com/info.txt"
    }
  ]
}

Reference Best Practices

1. Choose the Right Reference Type

   • Use image for primary visual representations
   • Use mainEntity to indicate the primary subject
   • Use sameAs for alternative versions
   • Use associatedMedia for related content
   • Use encodesCreativeWork for embedded content

2. Structured vs. Direct References

   • Use structured references when additional metadata is needed
   • Use direct URL references for simple links
   • Be consistent within your implementation
   • Document your reference strategy

3. Reference Maintenance

   • Keep URLs up to date
   • Validate references regularly
   • Document reference relationships
   • Handle missing references gracefully