What it the coordinate system of the vertex arrays in the quantized-mesh data?

I know that the quantized mesh vertex values are zigzag encoded 3-d coordinates but are they based on the cartesian lat/lon/ht values or the ECEF coordinates of the vertices?


Take a look at the reference doc for QuantizedMeshTerrainData: http://cesiumjs.org/Cesium/Build/Documentation/QuantizedMeshTerrainData.html

If you look at the example, it says

    quantizedVertices : new Uint16Array([// order is SW NW SE NE
                                         // longitude
                                         0, 0, 32767, 32767,
                                         // latitude
                                         0, 32767, 0, 32767,
                                         // heights
                                         16384, 0, 32767, 16384]),

Is that what you’re looking for?