Other DEM file format ?

[routeconverter]

Is there a possibility that RC became able to read and use DEM files in other format ? GeoTIFF or BIL/HDR for example ?

Yes, it's possible to extend the supported formats. The ElevationService interface looks like this:
https://github.com/cpesch/RouteConverter...rvice.java

The HGT files as an inspiration is here:
https://github.com/cpesch/RouteConverter...Files.java

DEM files are raster data, apart from HGT the only raster file format RC can handle is MBTiles, the only possible projection is web mercator. For anything beyond that I would suggest to use a GIS.

The API to fulfill is

Double getElevationFor(double longitude, double latitude) throws IOException;

with WGS84 coordinates. If @tybern wants to spend time parsing other files which need to be queried with other algorithms – why not try it?