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brwalker3 post(s)
#08-Jul-20 09:19

Hi

I am attempting to use a LAS dataset downloaded from Elvis (Australia lidar data portal). I can import a sample of the data and interpolate (Kriging) to a DEM just fine. I am trying to link to the files as a LAS Data Source. This creates a drawing and table without problems but I cannot transform the data set to a DEM. A background task appears to be running but the Add Component button never appears.

Can someone please confirm or deny that I should be able to interpolate a las data source without needing to import it.

A 68MB sample of the data is available

https://1drv.ms/u/s!AiqmE3l0u8EggpUfsCtBfltftebQNA?e=Vx1XbP

Thanks

Bernard

rk
395 post(s)
#08-Jul-20 10:09

Not sure, but perhaps Manifold is calculating the preview? Try zooming in (a lot) before Transform.

Dimitri

6,104 post(s)
#08-Jul-20 12:14

Sounds like Manifold is calculating the index.

I should be able to interpolate a las data source without needing to import it.

Yes, of course. There is an example of exactly that in the LAS, LAZ LiDAR topic.

I strongly suggest a review of that topic, and also the Tools - Index LiDAR Files topic. Think ahead and build indices on LiDAR files before you need them, so when you want to work with them it goes really fast.

You can also build LiDAR indices using Viewer, so that's always easy to do on spare machines, on whatever machine hosts files if it is on your local network, etc.

Dimitri

6,104 post(s)
#08-Jul-20 12:35

Couldn't resist trying the sample data...

A 68MB sample of the data is available

https://1drv.ms/u/s!AiqmE3l0u8EggpUfsCtBfltftebQNA?e=Vx1XbP

That file looks like it is not a LAS file. Whenever I'm in doubt about a file, I try the canonical reference, LASTools. Download the free version of LASTools from https://rapidlasso.com/lastools/ If LASTools don't work with a "las" file, that's an almost sure-fire indication the file is not a LAS file.

I tried using both lasview and lasinfo, and neither would work with the example StHelens2018-C1-AHD_6105433_GDA2020_55.las from the sample data link. So... I wouldn't expect Manifold to work with it either (it doesn't).

brwalker3 post(s)
#08-Jul-20 13:18

Yes my apologies - In an attempt to find a "small" sample to share I appeared to have gathered up a corrupt tile from Elvis. Probably the reason it was small. I had been doing my testing on full tiles (280+ MB) up to that point. Oh and I had previously read the help files and ensured the file was indexed.

The following link is to a tiny subset of a tile I produced using Global Mapper. This time I tested that it imports OK in to M9 and can be transformed. However, when linked as a data source I have the same problem. I cannot transform it.

https://1drv.ms/u/s!AiqmE3l0u8EghYtrO58EohHY0LzRXg?e=RkXlLI

Apologies again to any one who might have wasted time testing the corrupt link

Dimitri

6,104 post(s)
#08-Jul-20 13:52

Works perfectly (see image below).

I think what's going on (just a guess) is that you weren't following the example in the topic step by step, so instead of creating a new map in the main part of the project and dropping the linked drawing into that map, you just opened the drawing and tried to work on that.

The difference between the two is that if you follow the topic exactly, you create a map in the main part of the project, which is writeable, and then when you go to create a new image as a result of kriging, the transform template can write that image (when you press Add Component) to the project.

In contrast, if you just open the linked drawing, the context is the inside of the las file, and you can't write an image into that, so there is no option to add a component.

See the discussion in the Project Pane topic, under "Portals to Other Worlds" and subsequent, where there are illustrations of how a project pane can contain sections that are not writeable, etc.

Attachments:
sthelens_aus_lidar.png

brwalker3 post(s)
#09-Jul-20 04:43

Thanks Dimitri. You guessed correctly and have resolved my issue. The "Portals to another world" topic is a good read. Also the explanation you gave in your last post was most revealing and from my perspective a bit of a mind shift given I come from other GIS platforms. Maybe it is worth linking to the Portals... discussion from the Getting Started / Importing & Linking help section. I personally would have found that helpful.

Dimitri

6,104 post(s)
#09-Jul-20 08:33

That sounds good to me. I've sent in a suggestion for that.

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