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I keep having this problem while doing a simple 3D visualization of my newly created DEM in QGIS via the threejs plugin.

I work in Balkan Zone 7 metric system and, when I try to visualise the DEM that I created from points (which were transformed in Balkan Zone 7) using the TIN interpolation method, I get a really, really tall 'church-spiral-like' column in my browser. I have to scroll all the way to the top just to see my visualization.

But, of course, if I change from metric to another CRS, I get flat terrain in my visualization while my threejs display's the following message:

The unit of current CRS is degrees, so the terrain may not appear well.

The problem doesn't seem to appear while working with free data like the ASTER GDEM or SRTM data for my country, no matter if they are set to WGS, Pseudo-Mercator or Balkan Zone 7, the topography and the terrain still appear well.

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    What's a "chechire"? I can only think you mean a "church spire" duckduckgo.com/?t=lm&q=church+spire&iax=1&ia=images – Spacedman Nov 22 '16 at 13:05
  • Yes, I get a really, really tall white collumn which looks like a church spire. On the top of the "church-spire" look-a-like column, is my visuelisation. So, I can't really use it for live presentations where I have to visualise immidiatelly on the spot. – birdybird03 Nov 22 '16 at 13:20
  • You need to share more about your threejs settings and setup. What gets in, what did you setup, what is the result looking like? – bugmenot123 Nov 22 '16 at 13:43
  • @bugmenot123 I think you missed the detail where I described my problem; please re-read my question again and the comment's - everything is there. In threejs, the default settings were used. Thanks! – birdybird03 Nov 22 '16 at 18:35
  • I think you missed that my suggestions were for you to get helpful answers. – bugmenot123 Nov 25 '16 at 8:57
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I've seen this effect for data that is well above sea level (ie, 2500M). The plugin visualizes the extent of the canvas (unless you've clipped the DEM to a smaller extent in the dialog that pops up when you double click the DEM entry in the list). The background canvas is treated at 0' elevation, so the data is much above baseline. If you don't have this problem with other DEM data for the same region, I assume you're working close to sea level, which suggests that the data you created has an incorrect elevation. Check the range of elevations in your data compared to known elevations for the region in general.

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