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Hola Alejandro, mira esto , aquí creo que tienes lo que buscas ,

https://tronpoonpo.blogspot.com/p/oruxdemdt05.html?m=1

y en Telegram un canal con los archivos

https://t.me/OruxDeMDT50

🅃🅁🄾🄽🄿🄾

Ostras, muchas gracias! Ahora le echo un vistazo a todo

Hi LaurentG,

when I talk about "conversion" I mean the change of .asc format to .dem + .hdr. This last format is the only one that is both supported by oruxmaps and it is not resolution-limited, therefore, it is possible for oruxmaps to read 2 m resolution .dem + .hdr DEM files.

Btw, I do have set the "Interpolate DEM altitudes" option. As you suggest, Sonny's .hgt files are perfectly fine, and I am really happy with them too. I tried to use more precise DEM files out of curiosity because I think the SHADOW map looks gorgeous and I am trying to get height readings as accurate as possible, but in the end they are probably not that useful for most applications. Even so, I think that it is nice to have the option.

Hi LaurentG, I followed your links and I think that you're confused with some concepts.

Sonny's Digital Terrain Models (https://data.opendataportal.at/dataset/dtm-spain) are made out of LiDAR data, which he has collected from public official sources. This data is indeed of higher resolution than 1" (which is approximately a 20x30 m region). BUT, he uses this data to create .hgt DEM files, which are limited to 1" resolution. This means that although the original data was way more precise, in order to distribute it with .hgt format the data has to be reduced to 1" resolution. Why you may ask? Probably because .hgt is a light-weight popular format for DEM files.

But this doesn't mean that higher resolution data can't be used with the app. As stated before, this data exists (for example, IGN has Digital Terrain Models of 5x5m and 2x2m resolution: http://centrodedescargas.cnig.es/CentroDescargas/index.jsp). This data is distributed with .asc format and, therefore, to be used with the app it should have .dem + .hdr format. I have recently discovered a post that describes how to perform this conversion easily: https://www.mendiak.net/viewtopic.php?t=58960. The problem of this data is that it requires A LOT of free storage (tens of GB). But this is going to be less of a problem in the following years, as new smartphones with more and more storage are coming.

After all, to perform the conversion is not that hard, but it would be easier if .asc files could be used directly with the app. At least, I think it would be interesting to add some sort of explanation on how to perform this conversion in the manual of OruxMaps. Thus, new users would not have such a difficult time.

Hi LaurentG, I think I did not made myself clear. I know that any .hgt file can be added to the OruxMaps/Dem directory. What I ask is the addition of new compatible formats. Currently, only .hgt and .dem + .hdr formats are compatible with the app, which could be better, because:

• .hgt is limited to 1" resolution
• .dem + .hdr is not limited in resolution, but it does not seem to be a popular format among free elevation data distributors. I've mostly seen GeoTiff and .asc formats for LiDar and other precise terrain elevation models. I know that they can be converted, but as far as I'm concerned it is a tricky process, at least for those that are new to GIS (like me). If someone knows of a detailed guide on how to perform the conversion to .dem + .hdr, I would appreciate it.

Thanks for replying.

Nowadays, there are highly accurate DEM files available on the Internet (such as these: http://centrodedescargas.cnig.es/CentroDescargas/catalogo.do?Serie=LIDA2) that have a lot more precision than SRTM-DTED and GTOPO30/SRTM30, that are capped at 1" resolution.

I think it would be great for Oruxmaps to add the possibility to read those files, for better cumulative heights and other related features. Even though these type of files are a lot larger, today's smartphones have large storage capacities too.