This is the same as this question for ArcGIS: Creating Directional Flow Arrows for sewer lines? but for QGIS.
I tried to follow the same approach as in ArcGIS, but I keep missing the mark. I think I am close with a Marker Line.
[GIS] How to create a symbol with directional arrows in QGIS 3
directionqgis-3symbology
Related Solutions
Most of the sewer pipes I've seen have the directional arrow at the end of the line, but I had users that wanted the directional arrows along the entire line, at a reasonable interval.
It was a 2-layer symbol, with a cartograhic line, and then a Marker line symbol with an interval of 13.
Also, I just used 2 different feature layers of the same featureclass: 1 with the arrows and 1 without (sometimes I would tie each to different a scale range).
here's the symbol on a 9.3 layer (don't have time to sort out a style file). You should be able to add it, set the data source and go from there to tweak the symbol.
Add an overlapping Marker Symbol line and make the Template as shown. For the marker symbol I used the Dimension Style set Solid Triangle 2 which points to the right. I resized it down from 18 points to 12 points.
Now I have a question for you. For the line ends marker I tried using the dual arrows and a green circle with a dot like you showed, but the circles are not centered on the ends of the lines. Are your green circle marker symbols at the line ends tied to the lines themselves or are they tied to extracted points from the line ends? (Note: The lines in the picture below do not split at every intersection for all lines).
Best Answer
Basically you already got it. Just change the following:
Instead of on
central pointselectwith interval:And rotate your marker (or choose a different one):