Create terrain with two isolate DEM

[medusaless]

I have two DEMs which are not adjacent to each other. Saying one is the Texa DEM and the other is Florida DEM. First i create terrain one by one and the result in cesium is good. But after i merge the DEM into a single one. I cannot see any terrain in map. I think maybe my mergeing DEM has some problem, but I cannot figure it out. Can you give me some suggestions? Do I have to deal with nodata cell and set its value to zero(some solution i find on internet) ?

[ahuarte47]

Gdalbuildvrt could help you

[andysfd]

I have a follow up question, Gdalbuildvrt works fine especially when combining a lower resolution global model with an high resolution local model. But is there a way to combine two models by editing the layer.json file?

Combining a global model with an local model, by enhancing the global model with further zoom levels and editing the json file works. But i can't find a way to make this work for non adjacent regions.

(i.e. Global model up to zoom level 11 with a local higher resolution EU region and NA region up to zoom level 15)