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How can we make 2 lines that meet each other (sitting on top of another), intersect each other in QGIS? How can we make a point between them?

enter image description here

The reason why I want to make an intersection is that I want to make routing work. (I want the route to go through that point instead of taking longer rotues.)

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    The tool in Vector --> Analysis Tool --> Line Intersection should do the work you want – matteo Sep 22 '15 at 13:24
  • @matteo The Line Intersection tool creates a new layer, and it analyzes all the intersection in the entire layer. Is there a way would to do it on just particular lines and on the same layer? Thank you. – WantIt Sep 22 '15 at 13:46
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    what about selecting the lines yu want and run the Line Intersection algorithm in the Processing Toolbox? It takes into account only your selection – matteo Sep 22 '15 at 13:51
  • @matteo I tried selecting the lines I want and use the tool, but it ended up like this, puu.sh/kkcpc/61feb0b45a.png it still processes the whole vector layer and asking to save the output to another layer. – WantIt Sep 22 '15 at 13:59
  • you have to use the Line Intersection algorithm through the Processing Toolbox.. if you have any selected features, Processing takes only these for the calculation – matteo Sep 22 '15 at 14:20
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I would suggest to (1) break lines at the intersection, then (2) extract node.

(1) Break lines at the intersection

From QGIS Processing Toolbox, go to GRASS GIS 7 | Vector and activate v.clean tool. There are several options in Cleaning tool but please choose break.

(2) Extract node at the intersection

Again in the GRASS GIS 7 | Vector tree, there is v.net.articulation tool. Start this tool and select the cleaned line layer (output from v.clean) as input layer.

QGIS has another tool to extract nodes (Vector geometry tools | Extract nodes), but this tool extract all vertices in the line layer... You'll end up with many unwanted points.

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