I have installed the traceDigitize tool from the experimental repository in QGIS 1.9.0 Lisboa. My understanding of the tool is that you have to:

  1. Add 2 layers to QGIS Desktop. My empty shapefile to which I will edit and a polygon file of an object I want to trace.
  2. Set Snapping Options on the polygon file
  3. Activate the 'trace Edit' tool and move my cursor to the polygon I created until it snaps
  4. Hold ctrl button and begin tracing.

It seems to be tracing along the polygon, but when I right click to end the edit I get an error message:

enter image description here enter image description here

I'm not sure what this means. I know this plugin is experimental, but the one thread I found about this tool implies it works. Am I doing something wrong?

Thanks, Mike


This plugin does not work with QGIS 1.9 (master) since the srs() method has been removed and replaced by the crs() method.

See the API documentation: http://doc.qgis.org/api/classQgsMapLayer.html

  • Is the method still relatively the same? Could I just change the call from layers.srs() to layers.crs()? – Mike Apr 11 '13 at 15:45
  • Sure, give it a try. It returns the same object as the previous srs() method. – gsherman Apr 11 '13 at 16:08
  • Hmmm...it doesn't look like either one of those modules are installed. I'm using the OSGEO4w installer to install QGIS 1.9. Is there a specific library I should be installing? I can't figure out which one it is when I scroll through all the libs. – Mike Apr 11 '13 at 16:38
  • Edit line 282 in vertexTracerTool.py, changing layerEPSG = layer.srs().epsq() to layerEPSG= layer.crs().epsg(). The path to it is shown in your screenshots posted with your original question – gsherman Apr 11 '13 at 18:51
  • Thanks for helping. That's the update I made. It's now telling me that 'QgsCoordinateReferenceSystem' object has no attribute 'epsg'. Any idea if they replaced/renamed this object as well in the crs() Method? – Mike Apr 11 '13 at 19:57

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