Build terrain with Cesium Terrain Builder with some isolate DEMs

I have two isolate DEM, assuming one is Texas DEM and the other is Florida DEM. The two state is not adjacent to each other and i want to create the terrain data for both by using Cesium Terrain Builder. Do I have to merge the two DEM into a single one before running CTB? Anthoer method is that I create terrain data one by one and merge the output .terrain files. Can this way render terrain correctly?

Cesium Terrain Builder is not an official part of the Cesium project, so I can’t speak to its capabilities. You might have better luck opening an issue on their Github repository.

Cesium ion ( can do exactly what you want and is supported by the team. You can sign up for a free ion Community account to process your data with it.

can you please tell me … 1. how to convert DEM file to JSON file ?
. 2. Supposed a i have DEM file how can i upload or put this onto CESIUM and run it ?

check this