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I'm trying to mimick a line symbol style that is comprised of the line and 2 alternating markers. I use an interval placement of 10 units for the 'blocks' (custom svg) and 5 for points, thus every second point is covered by a block. With this trick all marker are aligned at the line properly. However, I'd wish to make the 'blocks' bend along with the line.

Is there any way I can achieve this?

enter image description here


I found a way by using a custom dash pattern (dash 5, space 5) and vertical marker lines with interval 5, instead of my custom svgs. This works perfectly well - but now I don't know how to add the point markers. I could use a simple marker with interval 5 and offset 2.5, but this is buggy because then the points wouldn't align along the line, where it bends..

enter image description here

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As you add the 'blocks' as markers, one suggestion would be to split the blocks marker into two or more parts, which follow each other. That way, each part would align with the line separately, effectively "following the line".


Another option would be to use simple line symbols with custom dash patterns for the bigger markers. This would avoid the need for x-offset. With an interval of 11 (all distances measured in mm) the following technique would give a better result. Square bracketed numbers are the line widths in mm. The first number in the dash pattern is a dash.

  • Simple line (thin, background line) [0.26].
  • Simple line (mid-thickness, special symbol) [2.26], dash{0,4,3,4}.
  • Simple line (thick and short, special symbol) [3.26], dash{0,3.5,0.5,3,0.5,3.5}
  • Marker line (the dot symbol) [], interval 11.

Since each part of the special symbol is a line symbol, it will follow the direction of the line. However, each part follows the line independently, so the symbol will not always keep its appearance very well, see the image.

QGIS Custom Dash Pattern

  • Thanks! I tried to do this and updated the original post. However, the problem is not solved yet. – Kay Feb 12 '14 at 16:54
  • ...found this posting: lists.osgeo.org/pipermail/qgis-user/2013-November/024934.html and I'm afraifd this feature request is still open, isn't it? I wonder why this isn't pushed more eagerly - it seems to be a common task to use different symbols with a given offset. And what is the offset along x all supposed to be good for if it doesn't align along the line? – Kay Feb 13 '14 at 9:12
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    With the idea of Mattias I solved the problem - Thanks a lot! For the issue with offsetted marker symbols, see this workaround gis.stackexchange.com/questions/86397/… – Kay Feb 13 '14 at 16:52

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