3D Tiles 1.1 draft

[lilleyse]

Preview link

Updates 3D Tiles to version 1.1. New capabilities include:

• Metadata: Metadata in 3D Tiles gains more expressiveness and flexibility, with a well-defined type system, new encoding options (e.g. JSON or binary), and a range of granularity options. Metadata may be associated with high-level objects like tilesets, tiles, or tile content groups, or with individual vertices and texels on glTF 2.0 geometry.
• Implicit Tiling: Common subdivision schemes and spatial index patterns may be declared without listing bounding volumes exhaustively. Reduces tileset size, and enables new optimizations including faster traversal, raycasting, random access, and spatial queries.
• glTF Tile Content: glTF 2.0 assets may be used directly as tile content, without intermediate formats, improving interoperability with 3D content and tooling ecosystems. Tiles may reference multiple contents — for organization, styling, and filtering — and contents may be collected into groups similar to map layers in mapping applications.

The following extensions introduced in 3D Tiles Next have been promoted to core:

• 3DTILES_metadata
• 3DTILES_implicit_tiling
• 3DTILES_content_gltf
• 3DTILES_multiple_contents

Further refinements to the wording and organization of the specification text are being tracked in #651