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I am trying to create a custom shapefile consisted of 16 waypoints orientated around an origin point. the 16 waypoints are to be 2m apart from the central waypoint (like an axis, with 0 being the central waypoint and 4 waypoints in each N,S,E,W direction). I have used geopackage to create this however i need to ensure they are exactly 2m apart. Is there a way to ensure this.

I also want to be able to use this shapefile in different locations, however do not want to drag the shapefile over long distances.

Is there a way to create this shapefile?

I can elaborate if needed - imagine placing an axis over your house and every 2m represents a sample point. Then you want to place the same axis over your friends house which is ~1,000km away.

Can we zoom to the friends house and snap the axis on easily?

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    Yes and yes. Now how do you want to go about it? What have you tried? – jbalk Oct 23 '18 at 20:59
  • First tried the geopackage to combine the 17 data sets. Then realized my points were not exactly 2m apart. Used plugin MMQGIS to set a grid and then draw them on. Still not exactly 2m apart in each direction. Then skipped geopackage and created individual shapefiles (points) in WGS 84. Merged all 17 into one shapefile (vector data mgt)- but now i lose out on using the attribute table. So went back to geopackage - but now i cannot simply move the package to a different location. I need to be able to snap this shapefile on but keep it open for attributes... again help is appreciated!!! @PolyGeo – QGIS Rookie Oct 23 '18 at 21:26
  • I've been trying, just looking for suggestions and help - -again newbie over here :) – QGIS Rookie Oct 23 '18 at 21:27
  • Please use the edit button beneath your question to revise it with any requested clarifications. – PolyGeo♦ Oct 23 '18 at 22:00
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First of all your origin point(s) layer needs to be in a metric projection like utm. Then you can create a fixed buffer vector --> geoprocessing tools --> buffer (fixed distance). Choose 2 as distance (=2m) and 4 as segments (to get 16 waypoints, vary if you need more or less). enter image description here

now go to vector --> geometry tools --> extract nodes choose your buffer layer and run it. The result looks like this:

enter image description here

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One way is to create the points with a custom azimuthal equidistant projected coordinate reference system. Set the center point to 0,0. Calculate or edit in the other points at 2 m from the center point. Depending on software, this projection may have a sphere-only implementation.

When you want to calculate the actual locations in latitude/longitude for a particular location, change the custom azimuthal equidistant ProjCRS's center point to match your location. Unproject the points to latitude-longitude. They will now have the correct latitude-longitude locations.

There's no way to make a set of coordinates in latitude-longitude and then move them any appreciable distance and have the coordinates still 'work'. Two meters will have different angular length depending on the location.

Another method would be to use a great circle or geodesic calculation like Vincenty and just build the points as you need to.

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