Why Load geojson with Cesium3DTileset in 2d is not same as GeoJsonDataSource?

[libofei2004]

I load a geojson with dataSources in 2d like this way:
viewer.dataSources.add(
Cesium.GeoJsonDataSource.load(
"../../Cesium-1.97/p1.json",
{
stroke: Cesium.Color.HOTPINK,
fill: Cesium.Color.PINK.withAlpha(0.5),
strokeWidth: 3
}
)
);
It seems like this:

Then I load the same geojson with Cesium3DTileset in 2d like this way:
const tileset = new Cesium.Cesium3DTileset({
url: "../../Cesium-1.97/tileset.json"
});
viewer.scene.primitives.add(tileset);
tileset.style = new Cesium.Cesium3DTileStyle({
color: "rgba(255, 0, 0, 0.8)"
});
the tileset.json content is：
{
"asset":{"version":"0.0","tilesetVersion":"1.0"},
"root":{
"boundingVolume":{
"region": [-3.14159,-1.57,3.14159,1.57,0,10000]
},
"geometricError":100000,
"content":{"uri":"p1.json"}
}
}
The geojson seems like this, it's bend.

In 3d mode, they looks the same,but in 2d mode,they are different, why?
How to make geojson with Cesium3DTileset looks the same as GeoJsonDataSource?

[ggetz]

So the root of the difference in curvature is likely due to a difference in the arc type used in either case, which will determine how a 3D line is projected into 2D space. Though its odd that Cesium3dTileset and DataSource are not consistant. My guess is they both should be using Rhumb lines and result in a "straight line" in 2D.

@lilleyse Can you confirm?

[lilleyse]

GeoJsonLoader (used by 3D Tiles) uses geodesic lines for performance reasons to avoid subsampling the geometry. Generally unless you have a tileset with the MAXAR_content_geojson extension you should be using GeoJsonDataSource which is a much more complete GeoJson implementation.

[libofei2004]

@lilleyse I use a tileset for drawing geojson is indeed for good performance，drawing by tileset is much more efficient than GeoJsonDataSource.

[ggetz]

Thanks @lilleyse! @libofei2004 I'm going to close the issue based on that answer. Let us know if there is still an issue.

[libofei2004]

Generally unless you have a tileset with the MAXAR_content_geojson extension you should be using GeoJsonDataSource which is a much more complete GeoJson implementation.

@ggetz @lilleyse I want to know how to have a tileset with the MAXAR_content_geojson extension？Does it make the geojson drawing a straight line？