1

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

  • Can you give some sample values and the results? – Mintx Apr 13 '15 at 20:23
  • I was using it in a different project with different shapefiles and I'm not sure what projection I was using then. 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. – TCF1988 Apr 13 '15 at 21:09
  • Not sure how much it will help but here is a screenshot of what it ends up giving me. I put in 100 feet for the distance and it drew it basically to infinity. The green line coming out of the top is the azimuth and distance drawn line. imgur.com/wqo1wcL – TCF1988 Apr 13 '15 at 21:20
  • Also, here is a screenshot of what I'm inputing. Doesn't matter if I choose default or feet under units, it will still draw it off into infinity. imgur.com/TGpzGmt – TCF1988 Apr 13 '15 at 21:28
1

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.

  • Chris, thank you so much for your help. I changed the project into NAD 1983 StatePlane Texas Central FIPS 4203 Feet as well as saving each individual shape file as NAD 1983 StatePlane Texas Central FIPS 4203 Feet. Still encountering the same issue with it drawing out to infinity. Thank you for your patience, I know what I'm missing is probably quite simple and I'm trying to get up to speed with QGIS. – TCF1988 Apr 13 '15 at 22:58
  • @TCF1988 Does the dialog box in the tool still say WGS84 as the coordinate system? If not and it's using the state plane zone you picked I'm afraid I'm out of ideas. It does appear that version was just recently released, so I wonder if there is a new bug in it. Are you drawing polylines or polygons? I also note that when it was updated for QGIS 2.0 and above support things changed from writing to a layer to writing to a memory layer, and I'm wondering if that has something to do with it (hence asking about what CRS the tool says it's using). – Chris W Apr 13 '15 at 23:09
  • It is drawing polylines. When I actually had it working properly I would convert the polylines to polygons once I was finished. The Dialog Box in the tool does say the State Plane, not WGS 84. – TCF1988 Apr 13 '15 at 23:39
0

I resolved this by always checking the "On the Fly" checkbox in the Project Setting then activating the Google Sattelite Map plugin. The google map seemed to pre-define the bounds for the Azimuth and Distance plugin to work properly.

0

The drawing length when using this plugin for me was not drawing correct distances and here is how I fixed it (QGIS 2.18.14):

I was already in a projected coordinate system (ftUS) and in the options menu I had my Distance Unit set to ft. That apparently was throwing off the distances for me. When I changed the distance unit back to Default, it started drawing at the correct scale.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.