Epsg 3875 or epsg 4326 while using gdal2tiles

CesiumJS
1

I currently use default gdal2tiles option to convert the generated orthophoto into epsg 3875 after which it generates the tiles in tms format. While rendering on the globe, we utilize the options tilingScheme: new Cesium.WebMercatorTilingScheme(), provided by Cesium.TileMapServiceImageryProvider.fromUrl()

  1. Is this a recommended approach to use epsg 3875 or should i generate gdal2tiles in tms format and after converting the orthophoto’s projection to 4326?

  2. For the terrain server i reproject it to epsg:4326 then convert it to quantized mesh format and dgenerate the terrain, so will doing the above approach ensure i have the same directory structure for both tile and terrain directories..

2

Hey @Haadi_M1 ,

It’s not clear what program you are using the “gdal2tiles” option to convert data, can you elaborate?

I believe epsg 3875 is the default for other web mapping clients like Leaflet, MapLibre GL, OpenLayers, so if you currently use or will use those it could make sense to leave it in that projection. However if you are are only using that TMS for Cesium with your mesh, then having them in the same EPSG is probably the best approach.

That being said, CesiumJS should handle them being in different EPSG’s anyway. Did you run into any issues in your approach or just asking about best practices?

3

No I did not run into any issues, my tiles were converted from 3875 to tms and my .terrain files from 4326 to quantized mesh 1.0 format