Inspect nodes on line in QGIS

Question

Is there an easy way to "inspect" the nodes that make up a line?

I am interested to see what node is the 1st, 2nd and so on along with their coordinates. Preferably in a list or something for a selected feature that is not in edit mode. I know I can add a marker to display the direction a line is digitilized at, but I am looking for the individual nodes.

I use another GIS program too that can do it very nicely (Intergraph), looking for a similar tool/method for QGIS.

Answer 1

I think you are looking for Vertex Editor (a table of coordinates of vertices).

1. make your layer editable
2. select the Vertex Tool, the Vertext editor panel is displayed
3. right click on a feature to get the list of coordinates
4. you can select a point in the vertext editor clicking on the ID, and the correspondent point on the canvas is also marked (blue circle)
5. you can even edit the coordinates, add and delete nodes...

Here is a screen shot:

UPDATE

Simple solution to list the coordinates without set it to editable. To list the coordinates of the first selected feature on the active layer enter the following Python command into the Python console of QGIS:

iface.activeLayer().selectedFeatures()[0].geometry()

If you need prettier output, you should extend the single line Python code to a plug-in.

Answer 2

A fast way to show the nodes of a selected line is to use the Geometry generator and to create a second multipoint symbol with the expression

if(is_selected( ), nodes_to_points($geometry),'')

Also, using the expression

if(is_selected( ), to_string(geom_to_wkt(nodes_to_points($geometry))),'')

you can create a label that contains all the coordinates of the nodes of the selected line. Activating the option Wrap on character and using the comma as separator, you can create an easy-to-read list.

In the picture an example.