3D Tiles 1.0 to 1.1 checklist

[lilleyse]

Checklist as we update 3D Tiles 1.0 to 3D Tiles 1.1. Most of these changes will go into the draft-1.1 branch.

Prerequisites

• Finish Revisions to the 3D Tiles Next extensions #630
• Finish Splitting EXT_mesh_features into multiple extensions glTF#56
• Finish Initial draft for 3D Tiles 1.1 schema #634

General

• Maintaining specifications for 3D Tiles 1.0, 1.1, and beyond #631
• Avoiding duplications for the JSON schema and implementations #632
• Fix broken links
• Remove mentions of 3D Tiles Next
• Refer to 1.1 sections instead of extensions wherever applicable
• What is the best way to incorporate s2, gltf, implicit tiling, metadata, and multiple contents?
• Use .gltf or .glb everywhere in examples

Specification

• Metadata
  • Restructure Metadata folder: Avoiding duplications for the JSON schema and implementations #632
  • Add 3DTILES_metadata concepts to the main specification. Link to Schema and PropertyTable folders in the reference implementation.
  • Move implicit tiling property table definition to Metadata/ReferenceImplementation/PropertyTable folder
• Implicit tiling
  • Add ImplicitTiling folder and README: Add ImplicitTiling subdirectory to 1.1 spec #655
  • Spatial data structures - rework to explain difference between explicit and implicit tiling. Add short summary and image for implicit tiling and link to ImplicitTiling.
• Multiple contents
  • Add to specification/README
  • Explain distinction between content and contents and rationale for having both (i.e. avoids a breaking change), and when to use one over the other (prefer content for single content, better for backwards compatibility)
• TileFormats
  • Update individual pages with a deprecation message. Point to migration guide.
  • Add glTF folder
    • Expand on intro summary in the main spec. Show how glTF can be used for heterogeneous 3D models, instanced models, and point clouds
    • Include recommended glTF extensions: Section in the 3D Tiles spec about recommended glTF extensions #602
    • Include details about feature identification and metadata
    • Include migration guide in appendix
    • Edit pass
• Update schema: Draft of directory layout for schemas for 3D Tiles 1.1 #654
  • Flesh out 3D Tiles Next schema descriptions: Draft of directory layout for schemas for 3D Tiles 1.1 #654 (comment)
  • Add deprecated where applicable - batch table, feature table, properties
  • Should specification/Styling/schema be moved to specification/schema/Styling? Move Styling/schema into schema/Styling #658
• File extensions and media types: #639
• Update version number
• Update date
• Update editors
• Update acknowledgements
• Update JSON encoding and URIs - https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#json-encoding
• Update Coordinate reference system to include tileset semantics
• Geometric error overview should not mandate monotonically decreasing
• Clean up transforms section. Move b3dm, i3dm, pnts specific information to their respective documents.
• Regenerate property reference
• Remove or replace specification.docx and specification.pdf
• Styling
  • Updates for 3D Tiles Next metadata or statistics?

Repo Cleanup

• Update main README
  • Add version history (include deprecations)
  • New banner image: https://demos.cesium.com/ferry-building
• Remove examples folder. Instead there should be a prominent link in the README to 3d-tiles-samples.
• Extensions
  • Update README
    • Remove 3D Tiles Next section
    • Borrow extension guidelines from glTF: https://github.com/KhronosGroup/glTF/tree/main/extensions.
  • Normalize formatting of 3DTILES_batch_table_hierarchy and 3DTILES_draco_point_compression
  • For each 3D Tiles Next extension add message at the top saying that it has been promoted to core in 3D Tiles 1.1
• Remove next folder
• Update reference card for 1.1 and generate new pdf
• Update Code of Conduct to the latest version used in CesiumJS: https://github.com/CesiumGS/cesium/blob/main/CODE_OF_CONDUCT.md
• Update or remove CONTRIBUTING.md
• Update or remove CREDITS.md
• Update or remove ECOSYSTEM.md
• Update Q-and-A.md
• Update RESOURCES.md
• Go through issues and see if any are relevant for 1.1
• Pending #631, create branch for 1.0 and tag 1.1 release

[wewindy]

Does version 1.1 accept translation contributions?

[lilleyse]

@onsummer yes, that would be a welcome contribution! You might want to wait until version 1.1 is more stable. That should happen in the next few months.

[wewindy]

@lilleyse Looking forward, thank you

[javagl]

The points

Fix broken links
Remove mentions of 3D Tiles Next
Refer to 1.1 sections instead of extensions wherever applicable

should largely be covered by #673. (Of course, the links should be checked again before the final merge. I had a look at https://github.com/tcort/markdown-link-check , and ... it may be OK, but I also have some utilities for that...)

_Edit

The point

Remove next folder

is also ~"done": The folder is not deleted, but made less visible (by not linking to it from the main README), and each .MD file in the folder carries a prominent note that "Next" is now "1.1"

[javagl]

As a short summary/wrap-up of the points that are not "ticked" yet:

• Maintaining specifications for 3D Tiles 1.0, 1.1, and beyond #631
• Pending Maintaining specifications for 3D Tiles 1.0, 1.1, and beyond #631, create branch for 1.0 and tag 1.1 release
  • The second one is actually part of a solution for the first one: The directory structure will likely not contain differentiation between 1.0 and 1.1, but instead, there will be tags for the versions. Details are tracked in the linked issue.

---

• Update date
• Update editors
• Update acknowledgements
  • Can be done before merging into main

---

• Regenerate property reference
  • This depends on wetzel - how well it works with the 2020-12 JSON schema has to be checked. NOTE: There are some in-page links to 'Property Reference' sections that do no longer exist. Depending on the schedule for further wetzel experiments, these might (have to) be omitted before merging into main

---

• Borrow extension guidelines from glTF: https://github.com/KhronosGroup/glTF/tree/main/extensions.
  • Some questions about the detail (i.e. how verbatim these guidelines will be copied) have to be sorted out, as well as our structuring for extensions that either work with 1.0 or 1.1 (see Maintaining specifications for 3D Tiles 1.0, 1.1, and beyond #631). We don't expect extensions for 1.1 to show up quickly and en masse, so this may have low priority for now.

---

• Update reference card for 1.1 and generate new pdf
  • This is still on my plate. I need to allocate a chunk of time for that, even though I assume that the "3D Tiles 1.1" reference card will largely be the "Next" one, with minor structure/wording changes for the "Next" -> "1.1" transition

---

• Go through issues and see if any are relevant for 1.1
  • This is still TODO (the actual actions may not be clear, but maybe the goal is exactly to sort out whether some of them have to be updated or can be closed)

[elfprince13]

Would really like to get #716 addressed before 1.1

[elfprince13]

#717 as well.

[javagl]

3D Tiles 1.1 has been published at https://docs.ogc.org/cs/22-025r4/22-025r4.html

Whatever was open here has to wait for the next version.