I posted a while ago and found out a little later that the way I asked the question was wrong.

//correct the latitude to go from 0 (north) to 180 (south),

// instead of 90(north) to -90(south)

latitude=90-latitude;

//correct the longitude to go from 0 to 360

longitude=180+longitude;

//find tile size from zoom level

double latTileSize=180/(pow(2,(17-zoom)));

double longTileSize=360/(pow(2,(17-zoom)));

//find the tile coordinates

int tilex=(int)(longitude/longTileSize);

int tiley=(int)(latitude/latTileSize);

Currently, Google, Bingmap, and OSM have a common method of calculating X and Y from latitude and longitude, and this is described.

ImageryProvider: new Cesium.TileCoordinatesImageryProvider();

shows that when checking the x,y coordinates arranged for each grid of Cesium, the value of tile.x, tile.y returned from cesium differs greatly from that of other systems.

Terrain tiling system / coordinate system - CesiumJS - Cesium Community

I’ve referenced posts you’ve answered before, but most of the links either expired or point to something else entirely.

Is there a separate part for managing these formulas in cesium?

I wonder how this part is calculated in Cesium.

The code using the formula has the structure of C#, but I am porting it to JS.