Exporting STM with Draped Raster to other 3rd party GIS or CAD Software

RE: Exporting STM with Draped Raster to other 3rd party GIS or CAD Software

Mathieu St-pierre — Fri, 11 Sep 2015 11:25:42 GMT

Hi Matt,

The true is very large terrain is kind of an emerging technology. Most file formats today assume that vector data are all loaded in memory at once and doesn't require lower resolutions representation of the terrain. Most software also assume the same.

I guess in a decade or so that technology might be more widely used like big raster data, which might encourage the development of common formats.

By the way what is the workflow you are trying to achieve? Which third party software do you want to use with big terrain?

Thanks,

Mathieu

RE: Exporting STM with Draped Raster to other 3rd party GIS or CAD Software

Matthew Frisina — Fri, 11 Sep 2015 01:49:05 GMT

G'day Mathieu

I managed to produce a 3D PDF from the file, but as you say, the resolution is very low; this is not desirable, I haven't tried the OBJ export as I was hoping to retain the high res quality of the imagery.

Cheers
Matt

RE: Exporting STM with Draped Raster to other 3rd party GIS or CAD Software

Matthew Frisina — Fri, 11 Sep 2015 01:47:04 GMT

Thank you for the reply Jan.

I'm new to Descartes and STMs, but not DTMs.

I just wanted to find out if there was any other CAD format(s) at all that the STM with high res draped image could be exported to, without losing the image quality, that could be imported by non-Bentley software.

I wasn't looking for anything specific, just if it was possible.
It's a shame that it isn't.

Thanks again
Matt

RE: Exporting STM with Draped Raster to other 3rd party GIS or CAD Software

Mathieu St-pierre — Wed, 09 Sep 2015 17:32:34 GMT

Hi Matthew,

The simple answer is no, no other application than Bentley Descartes can display STM data at full resolution.

And an export to OBJ or 3D PDF will most of the time result in lost of resolution.

Thanks,

Mathieu

RE: Exporting STM with Draped Raster to other 3rd party GIS or CAD Software

Pascal Cloutier — Wed, 09 Sep 2015 14:55:06 GMT

Matt,

You can try exporting to the "OBJ" format (MicroStation > file > export > OBJ...). It should retain the draping, but do expect some degree of quality loss.

If it doesn't answer your question, you enconter problems, or if there is a specific format you are looking to export into. Let me know.

Pascal

RE: Exporting STM with Draped Raster to other 3rd party GIS or CAD Software

fmcallis — Wed, 09 Sep 2015 13:03:44 GMT

RE: Exporting STM with Draped Raster to other 3rd party GIS or CAD Software

Jan Šlegr — Wed, 09 Sep 2015 05:49:15 GMT

Hi Matt,

[quote user="Matthew Frisina"]Is it possible to export an STM with a draped raster, for import and use in any 3rd party software?[/quote]

As far as I know it's not possible. The reason is simple: There is not any standard widely used data format that allows to share this type of data. STM is Bentley proprietary format developed by Bentley to allow to handle large DTM data. Draping is not even format, but just a technology (a lot of math formulas) how to dynamically project raster data to STM data. So to export draping is even more complicated, because the target application has also to know how to project raster data to terrain geometry.

[quote user="Matthew Frisina"]I have managed to create an STM and have draped a raster successfully, it looks great, but the problem is, my manager is asking if we can export the file so it can be used by the client.[/quote]

Any such widely formulated question cannot be answered. What does it mean "client"? What software does he use? Are there any any conditions or requirements in place?

You can convert your STM to DTM, which is standard MicroStation element. It opens some possibilities how to export and share terrain data. But any conversion always mean some data lost (no exception), so it's the place where requirememts have to be analyzed: Is the whole terrain your priority? Or do you need a small part? Or is it acceptable to split the terrain into more independent DTM elements?

I am not sure how raster draping is handled when STM is converted into DTM, because different technology is used, but raster draping to "standard surfaces" like DTM or triangles is supported not only by Descartes, but also by other Bentley software.

[quote user="Matthew Frisina"]Is there any software, Bentley (non Descartes) or other 3rd party GIS or CAD software, that I can export this file to and retain the full resolution as displayed in my file?[/quote]

I guess STM is now supported by Descartes only (including other products which includes Descartes functionality like Bentley Map Enterprise), but maybe somebody else will be able to provide more information.

[quote user="Matthew Frisina"]If it is not possible to do this; can anyone tell me what the purpose is of being able to create an STM and drape a high resolution raster, if the file can not be communicated to a third party?[/quote]

The main reason is of course to able to work with large DTM data. I agree the ability to share data is also very important (and Bentley do an excelent job here, I don't know any other software company so focused to data sharing and import/export/edit functionality), but the export and sharing adds value to data creation only. It's not an exception that specialized software uses own format and technology, so data cannot be shared directly but has to be converted into some common format (which doesn't exist for large DTM data).

With regards,

Jan