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I was wondering if there is a plugin, or a field calculation in QGIS to calculate a points rotation angle. ETGeoWizards has a tool that allows you to calculate a point layer rotation angle from a source line layer. Does anyone know of a similar process within QGIS?

Thanks...

  • What is that? An angle to rotate the point layer so it best matches (overlaps) the line one? – lynxlynxlynx Feb 7 '13 at 23:44
  • Yes and No. Its to know the cardinal direction of a point, in reference to a line. For example, the angle a house faces a street. Is the house facing 75 degrees north? – Ryan Garnett Feb 8 '13 at 0:41
  • But a house is not a point, you usually have a clear edge or face (2d) to construct an angle and compare to. With just a line and a point, you can get any angle you want from out of them. You need another anchoring point or some other constraint. Is this the angle of the line of minimal distance between the two? – lynxlynxlynx Feb 8 '13 at 9:24
  • Yes, I am aware of this. This process is for 3D modeling, so it is taken care of a different way. – Ryan Garnett Feb 8 '13 at 15:53
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    Points in GIS have no orientation. Unless you were to go and specify one as an attribute. What you want is the angle of the line, perpindicular to a point. Same method as noted in my answer below, me thinks. – Willy Feb 10 '13 at 10:20
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I recommend these

How to add Direction and Distance to attribute table?

http://hub.qgis.org/wiki/quantum-gis/Vector_intersection_-_angles

| improve this answer | |
  • Thank you, but these are for line segments. I am looking for a point, with reference to a line. – Ryan Garnett Feb 8 '13 at 15:55

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