cesium/CHANGES.md

CesiumJS is a JavaScript library for creating 3D globes and 2D maps in a web browser without a plugin.

# Change Log

### 1.101 - 2023-01-02

#### Major Announcements :loudspeaker:

- Starting with version 1.102, CesiumJS will default to using a WebGL2 context for rendering. WebGL2 is widely supported on all platforms and this change will result in better feature support across devices, especially mobile.
  - WebGL1 will still be supported. If WebGL2 is not available, CesiumJS will automatically fall back to WebGL1.
  - In order to work in a WebGL2 context, any custom materials, custom primitive or custom shaders will need to be upgraded to use GLSL 300.
  - Otherwise to request a WebGL 1 context, set `requestWebgl1` to `true` when providing `ContextOptions` as shown below:
    ```js
    const viewer = new Viewer("cesiumContainer", {
      contextOptions: {
        requestWebgl1: true,
      },
    });
    ```

#### @cesium/engine

##### Additions :tada:

- Added `vertexShadowDarkness` parameter to `Globe` to control the amount of darkness of the vertex shadow when terrain lighting is enabled. [#10914](https://github.com/CesiumGS/cesium/pull/10914)
- Added experimental support for 3D Tiles voxels with the [`3DTILES_content_voxels`](https://github.com/CesiumGS/3d-tiles/tree/voxels/extensions/3DTILES_content_voxels) extension. The current implementation is intended for development use, as the voxel format has not yet been finalized and is subject to breaking changes without deprecation.

##### Fixes :wrench:

- Fixed a bug where the scale of a `PointPrimitive` was incorrect when `scaleByDistance` was set to a `NearFarScalar`. [#10912](https://github.com/CesiumGS/cesium/pull/10912)
- Fixed glTF models with a mix of Draco and non-Draco attributes. [#10936](https://github.com/CesiumGS/cesium/pull/10936)
- Fixed a bug where billboards with `alignedAxis` properties were not properly aligned in 2D and Columbus View. [#10965](https://github.com/CesiumGS/cesium/issues/10965)
- Fixed a bug where \*.ktx2 image loading from a URI failed. [#10869](https://github.com/CesiumGS/cesium/pull/10869)
- Fixed a bug where a `Model` would sometimes disappear when loaded in Columbus View. [#10945](https://github.com/CesiumGS/cesium/pull/10945)
- Fixed a bug where the entity collection of a `GpxDataSource` did not have the `owner` property set. [#10921](https://github.com/CesiumGS/cesium/issues/10921)
- Fixed the JSDoc and TypeScript definitions of arguments in `Matrix2.multiplyByScalar`, `Matrix3.multiplyByScalar`, and several functions in the `S2Cell` class. [#10899](https://github.com/CesiumGS/cesium/pull/10899)
- Fixed a bug where `result` parameters were omitted from the TypeScript definitions. [#10864](https://github.com/CesiumGS/cesium/issues/10864)

#### Deprecated :hourglass_flowing_sand:

- `ContextOptions.requestWebgl2` was deprecated in CesiumJS 1.101 and will be removed in 1.102. Instead, CesiumJS will default to using a WebGL2 context for rendering. Use `ContextOptions.requestWebgl1` to request a WebGL1 or WebGL2 context.

#### @cesium/widgets

##### Additions :tada:

- Added `viewerVoxelInspectorMixin` and `VoxelInspector` to support experimental 3D Tiles voxels.

### 1.100 - 2022-12-01

#### Major Announcements :loudspeaker:

- CesiumJS is now published alongside two smaller packages `@cesium/engine` and `@cesium/widgets` [#10824](https://github.com/CesiumGS/cesium/pull/10824):
  - The source code has been paritioned into two folders: `packages/engine` and `packages/widgets`.
  - These workspaces packages will follow semantic versioning.
  - These workspaces packages will be published as ES modules with TypeScript definitions.
  - In the combined CesiumJS release, the `Source` folder only contains the following:
    - `Cesium.js`
    - `Cesium.d.ts`
    - `Assets`
    - `ThirdParty`
    - `Widgets`(CSS files only)
  - The ability to import modules and TypeScript definitions from individual files has been removed. Any imports should originate from the `cesium` module (`import { Cartesian3 } from "cesium";`) or the combined `Cesium.js` file (`import { Cartesian3 } from "Source/Cesium.js";`);

### 1.99 - 2022-11-01

#### Major Announcements :loudspeaker:

- Starting with version 1.100, CesiumJS will be published alongside two smaller packages `@cesium/engine` and `@cesium/widgets` [#10824](https://github.com/CesiumGS/cesium/pull/10824):
  - The source code will been paritioned into two folders: `packages/engine` and `packages/widgets`.
  - These workspaces packages will follow semantic versioning.
  - These workspaces packages will be published as ES modules with TypeScript definitions.
  - The combined CesiumJS release will continue to be published, however, the `Source` folder will only contain the following:
    - `Cesium.js`
    - `Cesium.d.ts`
    - `Assets`
    - `ThirdParty`
    - `Widgets`(CSS files only)
  - The ability to import modules and TypeScript definitions from individual files will been removed. Any imports should originate from the `cesium` module (`import { Cartesian3 } from "cesium";`) or the combined `Cesium.js` file (`import { Cartesian3 } from "Source/Cesium.js";`);

##### Additions :tada:

- Added support for I3S 3D Object and IntegratedMesh Layers. [#9634](https://github.com/CesiumGS/cesium/pull/9634)

##### Deprecated :hourglass_flowing_sand:

- The viewer parameter in `KmlTour.prototype.play` was deprecated in Cesium 1.99. It will be removed in 1.100. Instead of a `Viewer`, pass a `CesiumWidget` instead. [#10845](https://github.com/CesiumGS/cesium/pull/10845)

##### Fixes :wrench:

- Fixed a bug where the scale of a `Model` was being incorrectly applied to its bounding sphere. [#10855](https://github.com/CesiumGS/cesium/pull/10855)
- Fixed a bug where rendering a `Model` with image-based lighting while specular environment maps were unsupported caused a crash. [#10859](https://github.com/CesiumGS/cesium/pull/10859)
- Fixed a bug where request render mode was broken when a ground primitive is added. [#10756](https://github.com/CesiumGS/cesium/issues/10756)

### 1.98.1 - 2022-10-03

- This is an npm only release to fix the improperly published 1.98.

### 1.98 - 2022-10-03

#### Breaking Changes :mega:

- As of the previous release (1.97), `new Model()` is an internal constructor and must not be used directly. Use `Model.fromGltf()` instead. [#10778](https://github.com/CesiumGS/cesium/pull/10778)

##### Additions :tada:

- Added support for the `WEB3D_quantized_attributes` extension found in some glTF 1.0 models. [#10758](https://github.com/CesiumGS/cesium/pull/10758)

##### Fixes :wrench:

- Fixed a bug where instanced models without normals would not render. [#10765](https://github.com/CesiumGS/cesium/pull/10765)
- Fixed a regression where `i3dm` with scale and without rotation would render incorrectly. [#10808](https://github.com/CesiumGS/cesium/pull/10808)
- Fixed a regression where instanced feature IDs were not processed correctly [#10771](https://github.com/CesiumGS/cesium/pull/10771)
- Fixed a regression where `Cesium3DTileFeature.setProperty()` was not creating properties for unknown property IDs. [#10775](https://github.com/CesiumGS/cesium/pull/10775)
- Fixed a regression where `pnts` tiles with `3DTILES_draco_point_compression` and <= 8 quantization bits were being rendered incorrectly. [#10794](https://github.com/CesiumGS/cesium/pull/10794)
- Fixed a regression where glTF models with unused nodes would crash [#10813](https://github.com/CesiumGS/cesium/pull/10813)
- Fixed a regression where tilesets would not load in multiple `Viewer`s. [#10828](https://github.com/CesiumGS/cesium/pull/10828)
- Fixed a bug where camera would not follow the `Viewer.trackedEntity` if it had a model with a `HeightReference` other than `NONE`. [#10805](https://github.com/CesiumGS/cesium/pull/10805)
- Fixed a bug where calling `removeAll` on a `ClippingPlaneCollection` attached to a `Model` would cause a crash. [#10827](https://github.com/CesiumGS/cesium/pull/10827)
- Fixed a bug where replacing a `Model`'s `ClippingPlaneCollection` with one of the same length would cause a crash. [#10831](https://github.com/CesiumGS/cesium/pull/10831)
- Fixed a bug where KMLs with a NetworkLink with viewRefreshMode=='onRegion' would cause Cesium to make numerous resource requests and possibly trigger an out of memory error. [#10790](https://github.com/CesiumGS/cesium/pull/10790)
- Fixed a bug where calling `Vector3DTileContent.getFeature` before a render update could result in no feature being returned. [#10819](https://github.com/CesiumGS/cesium/pull/10819)

### 1.97 - 2022-09-01

#### Major Announcements :loudspeaker:

- CesiumJS has switched to a new architecture for loading glTF models and tilesets to enable:
  - User-defined GLSL shaders via [`CustomShader`](Documentation/CustomShaderGuide/README.md)
  - Support for [3D Tiles Next](https://cesium.com/blog/2021/11/10/introducing-3d-tiles-next/) metadata extensions: [`EXT_structural_metadata`](https://github.com/CesiumGS/glTF/tree/proposal-EXT_structural_metadata/extensions/2.0/Vendor/EXT_structural_metadata), [`EXT_mesh_features`](https://github.com/CesiumGS/glTF/tree/proposal-EXT_mesh_features/extensions/2.0/Vendor/EXT_mesh_features) and [`EXT_instance_features`](https://github.com/CesiumGS/glTF/tree/3d-tiles-next/extensions/2.0/Vendor/EXT_instance_features)
  - Support for [`EXT_mesh_gpu_instancing`](https://github.com/KhronosGroup/glTF/tree/main/extensions/2.0/Vendor/EXT_mesh_gpu_instancing)
  - Support for [`EXT_meshopt_compression`](https://github.com/KhronosGroup/glTF/tree/main/extensions/2.0/Vendor/EXT_meshopt_compression)
  - Texture caching across different tiles
  - Numerous bug fixes
- Usage notes for the new glTF architecture:
  - Those using `ModelExperimental.fromGltf()` should now use `Model.fromGltf()`.
  - The `enableModelExperimental` flag was removed, as tilesets and entities always use the new architecture.
  - The new implementation of `Model` uses the same public API as before, so no other changes are necessary.

#### Breaking Changes :mega:

- glTF 1.0 assets are no longer fully supported. glTF 1.0 techniques are converted to PBR materials where possible, but more complex techniques will no longer function correctly. If custom GLSL shaders are needed, use `CustomShader` instead. [#10648](https://github.com/CesiumGS/cesium/pull/10648)
- The glTF 2.0 extension `KHR_techniques_webgl` and `KHR_materials_common` are also no longer fully supported. Materials are converted to PBR materials where possible.
- Support for rendering instanced models on the CPU has been removed.
- `Model.gltf`, `Model.basePath`, `Model.pendingTextureLoads` (properties), and `Model.dequantizeInShader` (constructor option) have been removed.
- `ModelMesh` and `ModelMaterial` have been removed.
- `new Model()` is an internal constructor and must not be used directly. Use `Model.fromGltf()` instead. [#10778](https://github.com/CesiumGS/cesium/pull/10778)

##### Additions :tada:

- `Model` can now classify other assets with a given `classificationType`. [#10623](https://github.com/CesiumGS/cesium/pull/10623)
- `Model` now supports back face culling for point clouds. [#10703](https://github.com/CesiumGS/cesium/pull/10703)
- Export asset files such as CSS in `package.json`, allowing bundlers to import without additional configuration. [#9212](https://github.com/CesiumGS/cesium/pull/9212)
- The `sideEffects` field in `package.json` is now specified, allowing more conservative bundlers like Webpack to enable tree shaking by default. [#10714](https://github.com/CesiumGS/cesium/pull/10714)
- Model entities now support `CustomShader`. [#10747](https://github.com/CesiumGS/cesium/pull/10747)

##### Fixes :wrench:

- Fixed bug with `Viewer.flyTo` where camera could go underground when target is an `Entity` with `ModelGraphics` with `HeightReference.CLAMP_TO_GROUND` or `HeightReference.RELATIVE_TO_GROUND`. [#10631](https://github.com/CesiumGS/cesium/pull/10631)
- Fixed issues running CesiumJS under Node.js when using ES modules. [#10684](https://github.com/CesiumGS/cesium/issues/10684)
- Fixed the incorrect lighting of instanced models. [#10690](https://github.com/CesiumGS/cesium/pull/10690)
- Fixed developer error with `Camera.flyTo` with an `orientation` and a `Rectangle` value for `destination`. [#10704](https://github.com/CesiumGS/cesium/issues/10704)
- Fixed rendering bug with points in .vctr format, where points wouldn't show until picked or styled. [#10707](https://github.com/CesiumGS/cesium/pull/10707)
- Fixed bounding volume calculations for glTF models with `KHR_mesh_quantization` and normalized positions. [#10741](https://github.com/CesiumGS/cesium/pull/10741)

### 1.96 - 2022-08-01

##### Major Announcements :loudspeaker:

- Built `Cesium.js` is no longer AMD format. This may or may not be a breaking change depending on how you use Cesium in your app. See our [blog post](https://cesium.com/blog/2022/07/19/build-tooling-updates-coming-to-cesiumjs/) for the full details. [#10399](https://github.com/CesiumGS/cesium/pull/10399)
  - Built `Cesium.js` has gone from `12.5MB` to `8.4MB` unminified and from `4.3MB` to `3.6MB` minified. `Cesium.js.map` has gone from `22MB` to `17.2MB`.
  - If you were ingesting individual ESM-style modules from the combined file `Build/Cesium/Cesium.js` or `Build/CesiumUnminified/Cesium.js`, instead use `Build/Cesium/index.js` or `Build/CesiumUnminified/index.js` respectively.
  - Using ESM from `Source` will require a bundler to resolve third party node dependencies.
  - `CESIUM_BASE_URL` should be set to either `Build/Cesium` or `Build/CesiumUnminified`.

##### Breaking Changes :mega:

- `Model.boundingSphere` now returns the bounding sphere in ECEF coordinates instead of the local coordinate system. [#10589](https://github.com/CesiumGS/cesium/pull/10589)

##### Additions :tada:

- Models and tilesets that use the `CESIUM_primitive_outline` extension can now toggle outlines at runtime with the `showOutline` property. Furthermore, the color of the outlines can now be controlled by the `outlineColor` property. [#10506](https://github.com/CesiumGS/cesium/pull/10506)
- Added optional `blurActiveElementOnCanvasFocus` option to set the behavior of blurring the active element when interacting with the canvas. [#10518](https://github.com/CesiumGS/cesium/pull/10518)
- Added `ModelExperimental.getNode` to allow users to modify the transforms of model nodes at runtime. [#10540](https://github.com/CesiumGS/cesium/pull/10540)
- Added support for point cloud styling for tilesets loaded with `ModelExperimental`. [#10569](https://github.com/CesiumGS/cesium/pull/10569)
- Upgraded earcut from version 2.2.2 to version 2.2.4 which includes 10-15% better performance in triangulation. [#10593](https://github.com/CesiumGS/cesium/pull/10593)

##### Fixes :wrench:

- Fixed crash when loading glTF models with the `EXT_mesh_features` and `EXT_structural_metadata` extensions without `channels` property. [#10511](https://github.com/CesiumGS/cesium/pull/10511)
- Fixed a crash in the 3D Tiles Feature Styling sandcastle that occurred when using `ModelExperimental`. [#10514](https://github.com/CesiumGS/cesium/pull/10514)
- Fixed improper handling of double-sided materials in `ModelExperimental`. [#10507](https://github.com/CesiumGS/cesium/pull/10507)
- Fixed a bug where the alpha component of `model.color` would not update in the 3D Models Coloring sandcastle when using `ModelExperimental`. [#10519](https://github.com/CesiumGS/cesium/pull/10519)
- Fixed a bug where .cmpt files were not cached correctly in `ModelExperimental`. [#10524](https://github.com/CesiumGS/cesium/pull/10524)
- Fixed a crash in the 3D Tiles Formats sandcastle when loading draco-compressed point clouds with `ModelExperimental`. [#10521](https://github.com/CesiumGS/cesium/pull/10521)
- Fixed a bug where per-feature post-processing was not working with `ModelExperimental`. [#10528](https://github.com/CesiumGS/cesium/pull/10528)
- Fixed error in `loadAndExecuteScript` and favorite icon lost in sandcaslte when CesiumJS was running in cross-origin isloated evironment.[#10515](https://github.com/CesiumGS/cesium/pull/10515)
- Fixed a bug where `Viewer.zoomTo` would continuously throw errors if a `Cesium3DTileset` failed to load.[#10523](https://github.com/CesiumGS/cesium/pull/10523)
- Fixed a bug where styles would not apply to tilesets if they were applied while the tileset was hidden. [#10582](https://github.com/CesiumGS/cesium/pull/10582)
- Fixed a bug where `.i3dm` models with quantized positions were not being correctly loaded by `ModelExperimental`. [#10598](https://github.com/CesiumGS/cesium/pull/10598)
- Fixed a bug where dynamic geometry was not marked as `ready`. [#10517](https://github.com/CesiumGS/cesium/issues/10517)

##### Deprecated :hourglass_flowing_sand:

- Support for rendering instanced models on the CPU has been deprecated and will be removed in CesiumJS 1.97. [#10589](https://github.com/CesiumGS/cesium/pull/10589)
- The polyfills `requestAnimationFrame` and `cancelAnimationFrame` have been deprecated and will be removed in 1.99. Use the native browser methods instead. [#10579](https://github.com/CesiumGS/cesium/pull/10579)

### 1.95 - 2022-07-01

##### Breaking Changes :mega:

- Tilesets rendered with `ModelExperimental` must set `projectTo2D` to true in order to be accurately projected and rendered in 2D / CV mode. [#10440](https://github.com/CesiumGS/cesium/pull/10440)

##### Additions :tada:

- Memory statistics for `ModelExperimental` now appear in the `Cesium3DTilesInspector`. This includes binary metadata memory, which is not counted by `Model`. [#10397](https://github.com/CesiumGS/cesium/pull/10397)
- Memory statistics for `ResourceCache` (used by `ModelExperimental`) now appear in the `Cesium3DTilesInspector`. [#10413](https://github.com/CesiumGS/cesium/pull/10413)
- Added support for rendering individual models in 2D / CV using `ModelExperimental`. [#10419](https://github.com/CesiumGS/cesium/pull/10419)
- Added support for rendering instanced tilesets in 2D / CV using `ModelExperimental`. [#10433](https://github.com/CesiumGS/cesium/pull/10433)
- Added `modelUpAxis` and `modelForwardAxis` constructor options to `Cesium3DTileset` [#10439](https://github.com/CesiumGS/cesium/pull/10439)
- Added `heightReference` to `ModelExperimental`. [#10448](https://github.com/CesiumGS/cesium/pull/10448)
- Added `silhouetteSize` and `silhouetteColor` to `ModelExperimental`. [#10457](https://github.com/CesiumGS/cesium/pull/10457)
- Added support for mipmapped textures in `ModelExperimental`. [#10231](https://github.com/CesiumGS/cesium/issues/10231)
- Added `distanceDisplayCondition` to `ModelExperimental`. [#10481](https://github.com/CesiumGS/cesium/pull/10481)
- Added support for `AGI_articulations` to `ModelExperimental`. [#10479](https://github.com/CesiumGS/cesium/pull/10479)
- Added `credit` to `ModelExperimental`. [#10489](https://github.com/CesiumGS/cesium/pull/10489)
- Added `asynchronous` to `ModelExperimental.fromGltf`. [#10490](https://github.com/CesiumGS/cesium/pull/10490)
- Added `id` to `ModelExperimental`. [#10491](https://github.com/CesiumGS/cesium/pull/10491)
- `ExperimentalFeatures.enableModelExperimental` now enables `ModelExperimental` for entities and CZML in addition to 3D Tiles. [#10492](https://github.com/CesiumGS/cesium/pull/10492)

##### Fixes :wrench:

- Fixed `FeatureDetection` for Microsoft Edge. [#10429](https://github.com/CesiumGS/cesium/pull/10429)
- Fixed broken links in documentation of `CesiumTerrainProvider`. [#7478](https://github.com/CesiumGS/cesium/issues/7478)
- Warn if `Cesium3DTile` content.uri property is empty, and load empty tile. [#7263](https://github.com/CesiumGS/cesium/issues/7263)
- Updated text highlighting for code examples in documentation. [#10051](https://github.com/CesiumGS/cesium/issues/10051)
- Updated ModelExperimental shader defaults to match glTF spec. [#9992](https://github.com/CesiumGS/cesium/issues/9992)
- Fixed shadow rendering artifacts that appeared in `ModelExperimental`. [#10501](https://github.com/CesiumGS/cesium/pull/10501/)

##### Deprecated :hourglass_flowing_sand:

- The `.getPropertyNames` methods of `Cesium3DTileFeature`, `Cesium3DTilePointFeature`, and `ModelFeature` have been deprecated and will be removed in 1.98. Use the `.getPropertyIds` methods instead.

### 1.94.3 - 2022-06-10

- Fixed a crash with vector tilesets with lines when clamping to terrain or 3D tiles. [#10447](https://github.com/CesiumGS/cesium/pull/10447)

### 1.94.2 - 2022-06-03

- This is an npm only release to fix the improperly published 1.94.1.

### 1.94.1 - 2022-06-03

##### Additions :tada:

- Added support for rendering individual models in 2D / CV using `ModelExperimental`. [#10419](https://github.com/CesiumGS/cesium/pull/10419)

##### Fixes :wrench:

- Fixed `Cesium3DTileColorBlendMode.REPLACE` for certain tilesets. [#10424](https://github.com/CesiumGS/cesium/pull/10424)
- Fixed a crash when applying a style to a vector tileset with point features. [#10427](https://github.com/CesiumGS/cesium/pull/10427)

### 1.94 - 2022-06-01

##### Breaking Changes :mega:

- Removed individual image-based lighting parameters from `Model` and `Cesium3DTileset`. [#10388](https://github.com/CesiumGS/cesium/pull/10388)
- Models and tilesets rendered with `ModelExperimental` must set `enableDebugWireframe` to true in order for `debugWireframe` to work in WebGL1. [#10344](https://github.com/CesiumGS/cesium/pull/10344)
- Removed `ImagerySplitPosition` and `Scene.imagerySplitPosition`. Use `SplitDirection` and `Scene.splitPosition` instead.[#10418](https://github.com/CesiumGS/cesium/pull/10418)
- Removed restriction on enabling `Scene.orderIndependentTranslucency` on iPad and iOS. [#10417](https://github.com/CesiumGS/cesium/pull/10417)

##### Additions :tada:

- Added `Cesium3DTileStyle.fromUrl` for loading a style from a url. [#10348](https://github.com/CesiumGS/cesium/pull/10348)
- Added `IndexDatatype.fromTypedArray`. [#10350](https://github.com/CesiumGS/cesium/pull/10350)
- Added `ModelAnimationCollection.animateWhilePaused` and `ModelAnimation.animationTime` to allow explicit control over a model's animations. [#9339](https://github.com/CesiumGS/cesium/pull/9339)
- Replaced `options.gltf` with `options.url` in `ModelExperimental.fromGltf`. [#10371](https://github.com/CesiumGS/cesium/pull/10371)
- Added support for 2D / CV mode for non-instanced tilesets rendered with `ModelExperimental`. [#10384](https://github.com/CesiumGS/cesium/pull/10384)
- Added `PolygonGraphics.textureCoordinates`, `PolygonGeometry.textureCoordinates`, `CoplanarPolygonGeometry.textureCoordinates`, which override the default `stRotation`-based texture coordinate calculation behaviour with the provided texture coordinates, specified in the form of a `PolygonHierarchy` of `Cartesian2` points. [#10109](https://github.com/CesiumGS/cesium/pull/10109)

##### Fixes :wrench:

- Fixed the rendering issues related to order-independent translucency on iOS devices. [#10417](https://github.com/CesiumGS/cesium/pull/10417)
- Fixed the inaccurate computation of bounding spheres for models not centered at (0,0,0) in their local space. [#10395](https://github.com/CesiumGS/cesium/pull/10395)
- Fixed the inaccurate computation of bounding spheres for `ModelExperimental`. [#10339](https://github.com/CesiumGS/cesium/pull/10339/)
- Fixed error when destroying a 3D tileset before it has finished loading. [#10363](Fixes https://github.com/CesiumGS/cesium/issues/10363)
- Fixed race condition which can occur when updating `Cesium3DTileStyle` before its `readyPromise` has resolved. [#10345](https://github.com/CesiumGS/cesium/issues/10345)
- Fixed label background rendering. [#10342](https://github.com/CesiumGS/cesium/issues/10342)
- Enabled support for loading web assembly modules in Edge. [#6541](https://github.com/CesiumGS/cesium/pull/6541)
- Fixed crash for zero-area `region` bounding volumes in a 3D Tileset. [#10351](https://github.com/CesiumGS/cesium/pull/10351)
- Fixed `Cesium3DTileset.debugShowUrl` so that it works for implicit tiles too. [#10372](https://github.com/CesiumGS/cesium/issues/10372)
- Fixed crash when loading a tileset without a metadata schema but has external tilesets with tile or content metadata. [#10387](https://github.com/CesiumGS/cesium/pull/10387)
- Fixed winding order for negatively scaled models in `ModelExperimental`. [#10405](https://github.com/CesiumGS/cesium/pull/10405)
- Fixed error when calling `sampleTerrain` over a large area that required lots of tile requests. [#10425](https://github.com/CesiumGS/cesium/pull/10425)

##### Deprecated :hourglass_flowing_sand:

- `Cesium3DTileStyle` constructor parameters of `string` or `Resource` type have been deprecated and will be removed in CesiumJS 1.96. If loading a style from a url, use `Cesium3DTileStyle.fromUrl` instead. [#10348](https://github.com/CesiumGS/cesium/pull/10348)
- `Cesium3DTileStyle.readyPromise` and `Cesium3DTileStyle.ready` have been deprecated and will be removed in CesiumJS 1.96. If loading a style from a url, use `Cesium3DTileStyle.fromUrl` instead. [#10348](https://github.com/CesiumGS/cesium/pull/10348)
- `Model.gltf`, `Model.basePath`, `Model.pendingTextureLoads` (properties), and `Model.dequantizeInShader` (constructor option) have been deprecated and will be removed in CesiumJS 1.97. [#10415](https://github.com/CesiumGS/cesium/pull/10415)
- Support for glTF 1.0 assets has been deprecated and will be removed in CesiumJS 1.97. Please convert any glTF 1.0 assets to glTF 2.0. [#10414](https://github.com/CesiumGS/cesium/pull/10414)
- Support for the glTF extension `KHR_techniques_webgl` has been deprecated and will be removed in CesiumJS 1.97. If custom GLSL shaders are needed, use `CustomShader` instead. [#10414](https://github.com/CesiumGS/cesium/pull/10414)
- `Model.boundingSphere` currently returns results in the model's local coordinate system, but in CesiumJS 1.96 it will be changed to return results in ECEF coordinates. [#10415](https://github.com/CesiumGS/cesium/pull/10415)

### 1.93 - 2022-05-02

##### Breaking Changes :mega:

- Temporarily disable `Scene.orderIndependentTranslucency` by default on iPad and iOS due to a WebGL regression, see [#9827](https://github.com/CesiumGS/cesium/issues/9827). The old default will be restored once the issue has been resolved.

##### Additions :tada:

- Improved rendering of ground and sky atmosphere. [#10063](https://github.com/CesiumGS/cesium/pull/10063)
- Added support for morph targets in `ModelExperimental`. [#10271](https://github.com/CesiumGS/cesium/pull/10271)
- Added support for skins in `ModelExperimental`. [#10282](https://github.com/CesiumGS/cesium/pull/10282)
- Added support for animations in `ModelExperimental`. [#10314](https://github.com/CesiumGS/cesium/pull/10314)
- Added `debugWireframe` to `ModelExperimental`. [#10332](https://github.com/CesiumGS/cesium/pull/10332)
- Added `GeoJsonSource.process` to support adding features without removing existing entities, similar to `CzmlDataSource.process`. [#9275](https://github.com/CesiumGS/cesium/issues/9275)
- `KmlDataSource` now exposes the `camera` and `canvas` properties, which are used to provide information about the state of the `Viewer` when making network requests for a [`Link`](https://developers.google.com/kml/documentation/kmlreference#link). Passing these values in the constructor is now optional.
- Prevent text selection in the Timeline widget. [#10325](https://github.com/CesiumGS/cesium/pull/10325)

##### Fixes :wrench:

- Fixed `GoogleEarthEnterpriseImageryProvider.requestImagery`, `GridImageryProvider.requestImagery`, and `TileCoordinateImageryProvider.requestImagery` return types to match interface. [#10265](https://github.com/CesiumGS/cesium/issues/10265)
- Various property and return TypeScript definitions were corrected, and the `Event` class was made generic in order to support strongly typed event callbacks. [#10292](https://github.com/CesiumGS/cesium/pull/10292)
- Fixed debug label rendering in `Cesium3dTilesInspector`. [#10246](https://github.com/CesiumGS/cesium/issues/10246)
- Fixed a crash that occurred in `ModelExperimental` when loading a Draco-compressed model with tangents. [#10294](https://github.com/CesiumGS/cesium/pull/10294)
- Fixed an incorrect model matrix computation for `i3dm` tilesets that are loaded using `ModelExperimental`. [#10302](https://github.com/CesiumGS/cesium/pull/10302)
- Fixed race condition during billboard clamping when the height reference changes. [#10191](https://github.com/CesiumGS/cesium/issues/10191)
- Fixed ability to run `test` and other support tasks from within the release zip file. [#10311](https://github.com/CesiumGS/cesium/pull/10311)

### 1.92 - 2022-04-01

##### Breaking Changes :mega:

- Removed `Cesium.when`. Any `Promise` in the Cesium API has changed to the native `Promise` API. Code bases using cesium will likely need updates after this change. See the [upgrade guide](https://community.cesium.com/t/cesiumjs-is-switching-from-when-js-to-native-promises-which-will-be-a-breaking-change-in-1-92/17213) for instructions on how to update your code base to be compliant with native promises.
- `ArcGisMapServerImageryProvider.readyPromise` will not reject if there is a failure unless the request cannot be retried.
- `SingleTileImageryProvider.readyPromise` will not reject if there is a failure unless the request cannot be retried.
- Removed links to SpecRunner.html and related Jasmine files for running unit tests in browsers.

##### Additions :tada:

- Added experimental support for the [3D Tiles 1.1 draft](https://github.com/CesiumGS/3d-tiles/pull/666). [#10189](https://github.com/CesiumGS/cesium/pull/10189)
- Added support for `EXT_structural_metadata` property attributes in `CustomShader` [#10228](https://github.com/CesiumGS/cesium/pull/10228)
- Added partial support for `EXT_structural_metadata` property textures in `CustomShader` [#10247](https://github.com/CesiumGS/cesium/pull/10247)
- Added `minimumPixelSize`, `scale`, and `maximumScale` to `ModelExperimental`. [#10092](https://github.com/CesiumGS/cesium/pull/10092)
- `Cesium3DTileset` now has a `splitDirection` property, allowing the tileset to only be drawn on the left or right side of the screen. This is useful for visual comparison of tilesets. [#10193](https://github.com/CesiumGS/cesium/pull/10193)
- Added `lightColor` to `ModelExperimental` [#10207](https://github.com/CesiumGS/cesium/pull/10207)
- Added image-based lighting to `ModelExperimental`. [#10234](https://github.com/CesiumGS/cesium/pull/10234)
- Added clipping planes to `ModelExperimental`. [#10250](https://github.com/CesiumGS/cesium/pull/10250)
- Added `Cartesian2.clamp`, `Cartesian3.clamp`, and `Cartesian4.clamp`. [#10197](https://github.com/CesiumGS/cesium/pull/10197)
- Added a 'renderable' property to 'Fog' to disable its visual rendering while preserving tiles culling at a distance. [#10186](https://github.com/CesiumGS/cesium/pull/10186)
- Refactored metadata API so `tileset.metadata` and `content.group.metadata` are more symmetric with `content.metadata` and `tile.metadata`. [#10224](https://github.com/CesiumGS/cesium/pull/10224)

##### Fixes :wrench:

- Fixed `Scene` documentation for `msaaSamples` property. [#10205](https://github.com/CesiumGS/cesium/pull/10205)
- Fixed a bug where `pnts` tiles would crash when `Cesium.ExperimentalFeatures.enableModelExperimental` was true. [#10183](https://github.com/CesiumGS/cesium/pull/10183)
- Fixed an issue with Firefox and dimensionless SVG images. [#9191](https://github.com/CesiumGS/cesium/pull/9191)
- Fixed `ShadowMap` documentation for `options.pointLightRadius` type. [#10195](https://github.com/CesiumGS/cesium/pull/10195)
- Fixed evaluation of `minimumLevel` on metadataFailure for TileMapServiceImageryProvider. [#10198](https://github.com/CesiumGS/cesium/pull/10198)
- Fixed a bug where models without normals would render as solid black. Now, such models will use unlit shading. [#10237](https://github.com/CesiumGS/cesium/pull/10237)

##### Deprecated :hourglass_flowing_sand:

- `ImagerySplitDirection` and `Scene.imagerySplitPosition` have been deprecated and will be removed in CesiumJS 1.94. Use `SplitDirection` and `Scene.splitPosition` instead.
- Tilesets and models should now specify image-based lighting parameters in `ImageBasedLighting` instead of as individual options. The individual parameters are deprecated and will be removed in CesiumJS 1.94. [#10226](https://github.com/CesiumGS/cesium/pull/10226)

### 1.91 - 2022-03-01

##### Breaking Changes :mega:

- In Cesium 1.92, `when.js` will be removed and replaced with native promises. `Cesium.when` is deprecated and will be removed in 1.92. Any `Promise` returned from a function as of 1.92 will switch the native `Promise` API. Code bases using cesium will likely need updates after this change. See the [upgrade guide](https://community.cesium.com/t/cesiumjs-is-switching-from-when-js-to-native-promises-which-will-be-a-breaking-change-in-1-92/17213) for instructions on how to update your code base to be compliant with native promises.
- Fixed an inconsistently handled exception in `camera.getPickRay` that arises when the scene is not rendered. `camera.getPickRay` can now return undefined. [#10139](https://github.com/CesiumGS/cesium/pull/10139)

##### Additions :tada:

- Added MSAA support for WebGL2. Enabled in the `Viewer` constructor with the `msaaSamples` option and can be controlled through `Scene.msaaSamples`.
- glTF contents now use `ModelExperimental` by default. [#10055](https://github.com/CesiumGS/cesium/pull/10055)
- Added the ability to toggle back-face culling in `ModelExperimental`. [#10070](https://github.com/CesiumGS/cesium/pull/10070)
- Added `depthPlaneEllipsoidOffset` to `Viewer` and `Scene` constructors to address rendering artifacts below the WGS84 ellipsoid. [#9200](https://github.com/CesiumGS/cesium/pull/9200)
- Added support for `debugColorTiles` in `ModelExperimental`. [#10071](https://github.com/CesiumGS/cesium/pull/10071)
- Added support for shadows in `ModelExperimental`. [#10077](https://github.com/CesiumGS/cesium/pull/10077)
- Added `packArray` and `unpackArray` for matrix types. [#10118](https://github.com/CesiumGS/cesium/pull/10118)
- Added more affine transformation helper functions to `Matrix2`, `Matrix3`, and `Matrix4`. [#10124](https://github.com/CesiumGS/cesium/pull/10124)
  - Added `setScale`, `setUniformScale`, `setRotation`, `getRotation`, and `multiplyByUniformScale` to `Matrix2`.
  - Added `setScale`, `setUniformScale`, `setRotation`, and `multiplyByUniformScale` to `Matrix3`.
  - Added `setUniformScale`, `setRotation`, `getRotation`, and `fromRotation` to `Matrix4`.
- Added `AxisAlignedBoundingBox.fromCorners`. [#10130](https://github.com/CesiumGS/cesium/pull/10130)
- Added `BoundingSphere.fromTransformation`. [#10130](https://github.com/CesiumGS/cesium/pull/10130)
- Added `OrientedBoundingBox.fromTransformation`, `OrientedBoundingBox.computeCorners`, and `OrientedBoundingBox.computeTransformation`. [#10130](https://github.com/CesiumGS/cesium/pull/10130)
- Added `Rectangle.subsection`. [#10130](https://github.com/CesiumGS/cesium/pull/10130)
- Added option to show tileset credits on screen. [#10144](https://github.com/CesiumGS/cesium/pull/10144)
- glTF copyrights now appear under the credits display. [#10138](https://github.com/CesiumGS/cesium/pull/10138)
- Credits are now sorted based on their number of occurrences. [#10141](https://github.com/CesiumGS/cesium/pull/10141)

##### Fixes :wrench:

- Fixed a bug where updating `ModelExperimental`'s model matrix would not update its bounding sphere. [#10078](https://github.com/CesiumGS/cesium/pull/10078)
- Fixed feature ID texture artifacts on Safari. [#10111](https://github.com/CesiumGS/cesium/pull/10111)
- Fixed a bug where a translucent shader applied to a `ModelExperimental` with opaque features was not being rendered. [#10110](https://github.com/CesiumGS/cesium/pull/10110)

### 1.90 - 2022-02-01

##### Additions :tada:

- Feature IDs for styling and picking in `ModelExperimental` can now be selected via `(tileset|model).featureIdIndex` and `(tileset|model).instanceFeatureIdIndex`. [#10018](https://github.com/CesiumGS/cesium/pull/10018)
- Added support for all types of feature IDs in `CustomShader`. [#10018](https://github.com/CesiumGS/cesium/pull/10018)
- Moved documentation for `CustomShader` into `Documentation/CustomShaderGuide/` to make it more discoverable. [#10054](https://github.com/CesiumGS/cesium/pull/10054)
- Added getters `Cesium3DTileFeature.featureId` and `ModelFeature.featureId` so the feature ID or batch ID can be accessed from a picked feature. [#10022](https://github.com/CesiumGS/cesium/pull/10022)
- Added `I3dmLoader` to transcode .i3dm to `ModelExperimental`. [#9968](https://github.com/CesiumGS/cesium/pull/9968)
- Added `PntsLoader` to transcode .pnts to `ModelExperimental`. [#9978](https://github.com/CesiumGS/cesium/pull/9978)
- Added point cloud attenuation support to `ModelExperimental`. [#9998](https://github.com/CesiumGS/cesium/pull/9998)

##### Fixes :wrench:

- Fixed an error when loading GeoJSON with null `stroke` or `fill` properties but valid opacity values. [#9717](https://github.com/CesiumGS/cesium/pull/9717)
- Fixed `scene.pickTranslucentDepth` for translucent point clouds with eye dome lighting. [#9991](https://github.com/CesiumGS/cesium/pull/9991)
- Added a setter for `tileset.pointCloudShading` that throws if set to `undefined` to clarify that this is disallowed. [#9998](https://github.com/CesiumGS/cesium/pull/9998)
- Fixes handling .b3dm `_BATCHID` accessors in `ModelExperimental` [#10008](https://github.com/CesiumGS/cesium/pull/10008) and [10031](https://github.com/CesiumGS/cesium/pull/10031)
- Fixed path entity being drawn when data is unavailable [#1704](https://github.com/CesiumGS/cesium/pull/1704)
- Fixed setting `tileset.imageBasedLightingFactor` has no effect on i3dm tile content. [#10020](https://github.com/CesiumGS/cesium/pull/10020)
- Zooming out is no longer sluggish when close to `screenSpaceCameraController.minimumDistance`. [#9932](https://github.com/CesiumGS/cesium/pull/9932)
- Fixed Particle System Weather sandcastle demo to work with new ES6 rules. [#10045](https://github.com/CesiumGS/cesium/pull/10045)

### 1.89 - 2022-01-03

##### Breaking Changes :mega:

- Removed `Scene.debugShowGlobeDepth`. [#9965](https://github.com/CesiumGS/cesium/pull/9965)
- Removed `CesiumInspectorViewModel.globeDepth` and `CesiumInspectorViewModel.pickDepth`. [#9965](https://github.com/CesiumGS/cesium/pull/9965)
- `barycentricCoordinates` returns `undefined` when the input triangle is degenerate. [#9175](https://github.com/CesiumGS/cesium/pull/9175)

##### Additions :tada:

- Added a `pointSize` field to custom vertex shaders for more control over shading point clouds. [#9960](https://github.com/CesiumGS/cesium/pull/9960)
- Added `lambertDiffuseMultiplier` property to Globe object to enhance terrain lighting. [#9878](https://github.com/CesiumGS/cesium/pull/9878)
- Added `getFeatureInfoUrl` option to `WebMapServiceImageryProvider` which reads the getFeatureInfo request URL for WMS service if it differs with the getCapabilities URL. [#9563](https://github.com/CesiumGS/cesium/pull/9563)
- Added `tileset.enableModelExperimental` so tilesets with `Model` and `ModelExperimental` can be mixed in the same scene. [#9982](https://github.com/CesiumGS/cesium/pull/9982)

##### Fixes :wrench:

- Fixed handling of vec3 vertex colors in `ModelExperimental`. [#9955](https://github.com/CesiumGS/cesium/pull/9955)
- Fixed handling of Draco quantized vec3 vertex colors in `ModelExperimental`. [#9957](https://github.com/CesiumGS/cesium/pull/9957)
- Fixed handling of vec3 vertex colors in `CustomShaderPipelineStage`. [#9964](https://github.com/CesiumGS/cesium/pull/9964)
- Fixes how `Camera.changed` handles changes in `heading`. [#9970](https://github.com/CesiumGS/cesium/pull/9970)
- Fixed handling of subtree root transforms in `Implicit3DTileContent`. [#9971](https://github.com/CesiumGS/cesium/pull/9971)
- Fixed issue in `ModelExperimental` where indices were not the correct data type after draco decode. [#9974](https://github.com/CesiumGS/cesium/pull/9974)
- Fixed WMS 1.3.0 `GetMap` `bbox` parameter so that it follows the axis ordering as defined in the EPSG database. [#9797](https://github.com/CesiumGS/cesium/pull/9797)
- Fixed `KmlDataSource` so that it can handle relative URLs for additional elements - video, audio, iframe etc. [#9328](https://github.com/CesiumGS/cesium/pull/9328)

### 1.88 - 2021-12-01

##### Fixes :wrench:

- Fixed a bug with .ktx2 textures having an incorrect minification filter. [#9876](https://github.com/CesiumGS/cesium/pull/9876/)
- Fixed incorrect diffuse texture alpha in glTFs with the `KHR_materials_pbrSpecularGlossiness` extension. [#9943](https://github.com/CesiumGS/cesium/pull/9943)

### 1.87.1 - 2021-11-09

##### Additions :tada:

- Added experimental implementations of [3D Tiles Next](https://github.com/CesiumGS/3d-tiles/tree/main/next). The following extensions are supported:
  - [3DTILES_content_gltf](https://github.com/CesiumGS/3d-tiles/tree/main/extensions/3DTILES_content_gltf) for using glTF models directly as tile contents
  - [3DTILES_metadata](https://github.com/CesiumGS/3d-tiles/tree/main/extensions/3DTILES_metadata) for adding structured metadata to tilesets, tiles, or groups of tile content
  - [EXT_mesh_features](https://github.com/KhronosGroup/glTF/pull/2082) for adding feature identification and feature metadata to glTF models
  - [3DTILES_implicit_tiling](https://github.com/CesiumGS/3d-tiles/tree/main/extensions/3DTILES_implicit_tiling) for a compact representation of quadtrees and octrees
  - [3DTILES_bounding_volume_S2](https://github.com/CesiumGS/3d-tiles/tree/main/extensions/3DTILES_bounding_volume_S2) for [S2](https://s2geometry.io/) bounding volumes
  - [3DTILES_multiple_contents](https://github.com/CesiumGS/3d-tiles/tree/main/extensions/3DTILES_multiple_contents) for storing multiple contents within a single tile
- Added `ModelExperimental`, a new experimental architecture for loading glTF models. It is disabled by default; set `ExperimentalFeatures.enableModelExperimental = true` to enable it.
- Added `CustomShader` class for styling `Cesium3DTileset` or `ModelExperimental` with custom GLSL shaders
- Added Sandcastle examples for 3D Tiles Next: [Photogrammetry Classification](http://sandcastle.cesium.com/index.html?src=3D%20Tiles%20Next%20Photogrammetry%20Classification.html&label=3D%20Tiles%20Next), [CDB Yemen](http://sandcastle.cesium.com/index.html?src=3D%20Tiles%20Next%20CDB%20Yemen.html&label=3D%20Tiles%20Next), and [S2 Globe](http://sandcastle.cesium.com/index.html?src=3D%20Tiles%20Next%20S2%20Globe.html&label=3D%20Tiles%20Next)

### 1.87 - 2021-11-01

##### Additions :tada:

- Added `ScreenOverlay` support to `KmlDataSource`. [#9864](https://github.com/CesiumGS/cesium/pull/9864)
- Added back some support for Draco attribute quantization as a workaround until a full fix in the next Draco version. [#9904](https://github.com/CesiumGS/cesium/pull/9904)
- Added `CumulusCloud.color` for customizing cloud colors. [#9877](https://github.com/CesiumGS/cesium/pull/9877)

##### Fixes :wrench:

- Point cloud styles that reference a missing property now treat the missing property as `undefined` rather than throwing an error. [#9882](https://github.com/CesiumGS/cesium/pull/9882)
- Fixed Draco attribute quantization in point clouds. [#9908](https://github.com/CesiumGS/cesium/pull/9908)
- Fixed crashes caused by the cloud noise texture exceeding WebGL's maximum supported texture size. [#9885](https://github.com/CesiumGS/cesium/pull/9885)
- Updated third-party zip.js library to 2.3.12 to fix compatibility with Webpack 4. [#9897](https://github.com/cesiumgs/cesium/pull/9897)

### 1.86.1 - 2021-10-15

##### Fixes :wrench:

- Fixed zip.js configurations causing CesiumJS to not work with Node 16. [#9861](https://github.com/CesiumGS/cesium/pull/9861)
- Fixed a bug in `Rectangle.union` with rectangles that span the entire globe. [#9866](https://github.com/CesiumGS/cesium/pull/9866)

### 1.86 - 2021-10-01

##### Breaking Changes :mega:

- Updated to Draco 1.4.1 and temporarily disabled attribute quantization. [#9847](https://github.com/CesiumGS/cesium/issues/9847)

##### Fixes :wrench:

- Fixed incorrect behavior in `CameraFlightPath` when using Columbus View. [#9192](https://github.com/CesiumGS/cesium/pull/9192)

### 1.85 - 2021-09-01

##### Breaking Changes :mega:

- Removed `Scene.terrainExaggeration` and `options.terrainExaggeration` for `CesiumWidget`, `Viewer`, and `Scene`, which were deprecated in CesiumJS 1.83. Use `Globe.terrainExaggeration` instead.

##### Additions :tada:

- Added `CloudCollection` and `CumulusCloud` for adding procedurally generated clouds to a scene. [#9737](https://github.com/CesiumGS/cesium/pull/9737)
- `BingMapsGeocoderService` now takes an optional [Culture Code](https://docs.microsoft.com/en-us/bingmaps/rest-services/common-parameters-and-types/supported-culture-codes) for localizing results. [#9729](https://github.com/CesiumGS/cesium/pull/9729)

##### Fixes :wrench:

- Fixed several crashes related to point cloud eye dome lighting. [#9719](https://github.com/CesiumGS/cesium/pull/9719)

### 1.84 - 2021-08-02

##### Breaking Changes :mega:

- Dropped support for Internet Explorer, which was deprecated in CesiumJS 1.83.

##### Additions :tada:

- Added a `polylinePositions` getter to `Cesium3DTileFeature` that gets the decoded positions of a polyline vector feature. [#9684](https://github.com/CesiumGS/cesium/pull/9684)
- Added `ImageryLayerCollection.pickImageryLayers`, which determines the imagery layers that are intersected by a pick ray. [#9651](https://github.com/CesiumGS/cesium/pull/9651)

##### Fixes :wrench:

- Fixed an issue where styling vector points based on their batch table properties would crash. [#9692](https://github.com/CesiumGS/cesium/pull/9692)
- Fixed an issue in `TileBoundingRegion.distanceToCamera` that caused incorrect results when the camera was on the opposite site of the globe. [#9678](https://github.com/CesiumGS/cesium/pull/9678)
- Fixed an error with removing a CZML datasource when the clock interval has a duration of zero. [#9637](https://github.com/CesiumGS/cesium/pull/9637)
- Fixed the ability to set a material's image to `undefined` and `Material.DefaultImageId`. [#9644](https://github.com/CesiumGS/cesium/pull/9644)
- Fixed render crash when creating a `polylineVolume` with very close points. [#9669](https://github.com/CesiumGS/cesium/pull/9669)
- Fixed a bug in `PolylineGeometry` that incorrectly shifted colors when duplicate positions were removed. [#9676](https://github.com/CesiumGS/cesium/pull/9676)
- Fixed the calculation of `OrientedBoundingBox.distancedSquaredTo` such that they handle `halfAxes` with magnitudes near zero. [#9670](https://github.com/CesiumGS/cesium/pull/9670)
- Fixed a crash that would hang the browser if a `Label` was created with a soft hyphen in its text. [#9682](https://github.com/CesiumGS/cesium/pull/9682)
- Fixed the incorrect calculation of `distanceSquaredTo` in `BoundingSphere`. [#9686](https://github.com/CesiumGS/cesium/pull/9686)

### 1.83 - 2021-07-01

##### Breaking Changes :mega:

- Dropped support for KTX1 and Crunch textures; use the [`ktx2ktx2`](https://github.com/KhronosGroup/KTX-Software) converter tool to update existing KTX1 files.

##### Additions :tada:

- Added support for KTX2 and Basis Universal compressed textures. [#9513](https://github.com/CesiumGS/cesium/issues/9513)
  - Added support for glTF models with the [`KHR_texture_basisu`](https://github.com/KhronosGroup/glTF/blob/master/extensions/2.0/Khronos/KHR_texture_basisu/README.md) extension.
  - Added support for 8-bit, 16-bit float, and 32-bit float KTX2 specular environment maps.
  - Added support for KTX2 images in `Material`.
  - Added new `PixelFormat` and `WebGLConstants` enums from WebGL extensions `WEBGL_compressed_texture_etc`, `WEBGL_compressed_texture_astc`, and `EXT_texture_compression_bptc`.
- Added dynamic terrain exaggeration with `Globe.terrainExaggeration` and `Globe.terrainExaggerationRelativeHeight`. [#9603](https://github.com/CesiumGS/cesium/pull/9603)
- Added `CustomHeightmapTerrainProvider`, a simple `TerrainProvider` that gets height values from a callback function. [#9604](https://github.com/CesiumGS/cesium/pull/9604)
- Added the ability to hide outlines on OSM Buildings and other tilesets and glTF models using the `CESIUM_primitive_outline` extension. [#8959](https://github.com/CesiumGS/cesium/issues/8959)
- Added checks for supported 3D Tiles extensions. [#9552](https://github.com/CesiumGS/cesium/issues/9552)
- Added option to ignore extraneous colorspace information in glTF textures and `ImageBitmap`. [#9624](https://github.com/CesiumGS/cesium/pull/9624)
- Added `options.fadingEnabled` parameter to `ShadowMap` to control whether shadows fade out when the light source is close to the horizon. [#9565](https://github.com/CesiumGS/cesium/pull/9565)
- Added documentation clarifying that the `outlineWidth` property will be ignored on all major browsers on Windows platforms. [#9600](https://github.com/CesiumGS/cesium/pull/9600)
- Added documentation for `KmlTour`, `KmlTourFlyTo`, and `KmlTourWait`. Added documentation and a `kmlTours` getter to `KmlDataSource`. Removed references to `KmlTourSoundCues`. [#8073](https://github.com/CesiumGS/cesium/issues/8073)

##### Fixes :wrench:

- Fixed a regression where older tilesets without a top-level `geometricError` would fail to load. [#9618](https://github.com/CesiumGS/cesium/pull/9618)
- Fixed an issue in `WebMapTileServiceImageryProvider` where using URL subdomains caused query parameters to be dropped from requests. [#9606](https://github.com/CesiumGS/cesium/pull/9606)
- Fixed an issue in `Screen