Page 1 of 1

Basic Question About Viewing SlopeShade Maps

Posted: Sat Mar 07, 2020 12:50 am
by carlc
To begin with I am amazed at the scope of this application. In 50 years of programming I have never seen so impressive an open-source application.

My needs are extremely simple. However, being a geologist/programmer, I can't find my way through so complex an application. My understanding of this field is just too superficial. All I want to do is to study the history of 49er mining activity hidden under the cover of the Klamath Mountain's dense vegetation. I want to use the USGS 3DEP's forthcoming "QL1 Lidar for the Carr, Hirz, and Delta Fire Impacted Watersheds" cloud data (las or laz) with a slopeshade map. The features I want to see are linear with a width of a meter or less. Here is a perfect example of what i want to do: https://www.fs.usda.gov/Internet/FSE_DO ... 536844.pdf.

Could some kind soul guide me through this either in CloudCompare or some other application? I'm pretty sure my use of this technique will lead others whom I work with to learn more about lidar.

Perhaps this is asking too much. If it is, I apologize.
Thank you

Re: Basic Question About Viewing SlopeShade Maps

Posted: Sun Mar 08, 2020 3:00 pm
by daniel
Thanks ;)

Well, I'm not the expert here neither, but I believe you could try to use the 'Rasterize' tool for that:
https://www.cloudcompare.org/doc/wiki/i ... #Hillshade

At least you can already create a raster from your point cloud. Either you simply keep the points with minimum altitude (to remove the vegetation), or if it's not sufficient, you will have to filter the vegetation out prior to use the Rasterize tool (you can try with the 'qCSF' plugin for instance).

And then you can play with the 'Hillshade' feature, or also export the raster as a file and process it in a more general GIS tool (QGis, etc.).