[GIS] QGIS Azimuth and Distance plugin length issue

azimuthdistancemetes-and-boundsqgisqgis-plugins

Relative newbie to QGIS and trying to figure out exactly what I'm doing wrong. A couple days ago I had azimuth and distance working perfectly. I was using it in a different project with different shapefiles and I'm not sure what projection I was using then.

I'm using QGIS Version 2.8.1-Wien and Azimuth and Distance Plugin Version 0.9.3

Now for some reason no matter what distance I put in it draws the line way off of the map. Before I was using default, but I've tried using both default and feet and it seems to make no difference.

enter image description here

I started over from scratch and everything is projected in EPSG:4326 WGS 84 and the project default is set to EPSG:4326 WGS 84. Whenever I draw to a temp layer it auto sets the projection to EPSG:4326 WGS 84 since one is not defined.

Here is a screenshot of what I'm inputting. Doesn't matter if I choose default or feet under units, it will still draw it off into infinity.

enter image description here

Best Answer

I did a quick glance at the code for the tool. It appears that default/feet choice is to specify a fixed conversion between feet and meters. This would make sense, because as I mentioned earlier in the context of metes-and-bounds you're usually using one of those units (or something archaic like chains or rods). But line 189 of the source code is just a straight conversion factor from feet to meters. It doesn't know how to account for other default units, let alone degrees for which there is no direct conversion.

So the solution is you need to reproject your data (right-click and save-as) and/or project into a projected coordinate system (for example a UTM zone or State Plane, you don't mention what area you're working in) that uses meters as default. I'm not sure if the tool would work correctly just with on-the-fly reprojection. Note that if you choose a CRS with feet as units, you'll still want to use the default rather than feet setting. You should only set that to feet if your CRS is in meters and you want to input feet.

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