How can I find depression contour lines?
I already have find depressions via Fill-method, but now I try to detect them by using the contour lines, anyone have an idea ?
[GIS] Finding depression with contour lines
arcgis-desktopcontoursink
Related Solutions
Since the distance between the lines in your two data sources can vary greatly (at least it looks like this on the picture), you might need to do some manual work. However, I'd suggest trying the Extend line GP tool (Editing toolbox) or Snap tool (same toolbox).
This tool extends line segments to the first intersecting feature within a specified distance. If no intersecting feature is within the specified distance, the line segment will not be extended.
You might also test to use the Load Objects to load features from one source to another and set snapping settings. I use it quite often when "merging" road datasets from different sources and it reduces amount of manual work that will be needed to get done anyway.
There is a great blog post from Esri, where you can get more tips on data processing for such cases. They mention also using Integrate tool, Trim line and some other custom GP tools the Esri Editing team has published.
Solved!
I've e-mailed the developer (Dominique Lyszczarz), and sent him the SHP. Turned out it was a bug in the add on. He corrected it and now it's working fine!
I've added some images to illustrate the import results. I've used a 1375 contour lines (features) SHP. But I'm still to push the limit!
The SHP imported into Blender:
TIN model out of the contour lines (also from Blender GIS add on):
Perspective view of the TIN model and the contour lines:
If someone wants to try it, just a tip: delete all the NULL value geometries/features, otherwise Blender GIS won't load it.
Now, to refine the model, it's just a matter of adding contour lines where necessary, before importing the SHP into Blender.
Hope it helps anyone looking for 3D representation using contour lines.
Best Answer
This ESRI blog post describes a method for finding depressions using contours. On a topo map depressions look like this:
Note that the above approach is not desgined to be programmatic, but simply relies on symbolizing the contour lines using different colors so that you can visually find lines which do not fit the pattern of stepwise increases.