Sean Lilley

Limited support for glTF 1.0 in the new model implementation

1

Fixes https://github.com/CesiumGS/cesium/issues/10613 glTF 1.0, `KHR_techniques_webgl`, and `KHR_materials_common` are no longer fully supported and are converted to PBR materials where possible via gltf-pipeline. The gltf-pipeline changes have been reviewed in https://github.com/CesiumGS/gltf-pipeline/pull/619.

Skinning broken for glTF 1.0 models with ModelExperimental

2

Several glTF 1.0 models aren't skinning or animating correctly in ModelExperimental. Interestingly the 2.0 versions of those models don't have any issues. It's possible the models were sanitized or fixed...

[`computeModelMatrix`](https://github.com/CesiumGS/cesium/blob/bd40c3179ac515cf6d2215a31d50fc88affcd200/Source/Scene/ModelExperimental/ModelExperimentalSceneGraph.js#L309-L330) takes `components.transform` into account but [`updateBoundingSphereAndScale`](https://github.com/CesiumGS/cesium/blob/bd40c3179ac515cf6d2215a31d50fc88affcd200/Source/Scene/ModelExperimental/ModelExperimental.js#L1851-L1871) does not. This means that if the b3dm has `RTC_CENTER` or the glTF has `CESIUM_RTC` -- both of which are set to `loader.components.transform`...

This a small regression in `ModelExperimental` If `modelMatrix` is changed it takes an update loop before `boundingSphere` is updated, unlike `Model` and `Cesium3DTileset` which update the `boundingSphere` on demand when...

Instead of outright dropping glTF 1.0 support we could try to do a best effort upgrade from glTF 1.0 to 2.0. It's not possible to upgrade glTF 1.0 shaders to...

Generate normals automatically for glTF 2.0 models

6

From the [glTF spec](https://github.com/KhronosGroup/glTF/tree/master/specification/2.0) > Implementation note: When normals are not specified, client implementations should calculate flat normals. This would replace the stopgap solution in https://github.com/AnalyticalGraphicsInc/cesium/pull/6501.

3D Tiles 1.0 to 1.1 checklist

5

Checklist as we update 3D Tiles 1.0 to 3D Tiles 1.1. Most of these changes will go into the [draft-1.1](https://github.com/CesiumGS/3d-tiles/tree/draft-1.1) branch. ### Prerequisites * [x] Finish https://github.com/CesiumGS/3d-tiles/pull/630 * [x] Finish...

3D Tiles 1.1 draft

1

### [Preview link](https://github.com/CesiumGS/3d-tiles/tree/draft-1.1/specification) Updates 3D Tiles to version 1.1. New capabilities include: * [Metadata](https://github.com/CesiumGS/3d-tiles/tree/draft-1.1/specification/Metadata): Metadata in 3D Tiles gains more expressiveness and flexibility, with a well-defined type system, new encoding...

Top-level information about tile content

2

Right now there's no place to put top-level information about tile content. Some use cases include: * If the tileset has glTF content, list out the `extensionsUsed` and `extensionsRequired` so...

Metadata inheritance

3

3D Tiles Next defines different levels of metadata granularity but it doesn't define the relationship or inheritance model of this metadata. There are a lot of ways this could be...