I am making an atlas of protected areas using QGIS. I am using version 2.12, but this question will probably also apply to version 2.14 as well.

Several points of interest (poi) objects are presented in this atlas. Some of these, like parking, information station and viewpoint are presented as icons. When these are close to oneother it is relevant to group the icons and align them (on a line) close to a centerpoint for the poi-objects. Currently this is done using desktop publishing tools and it looks like this:

enter image description here

I would like to pull as much as possible of this process into the QGIS atlas system. We have many of the protecteda areas, so the gain of automating the process is potentially big.

How can this be done in QGIS?

Also see question Using FME to aggregate POI to one point for context.

  • 2
    not quite shure wether you're talking about web application (online atlas) od atlas feature (printing), but why not aligning the poi point features theirselves in a suitable way? i would use two feature classes, one with the real positions and one for the graphical representations in the atlas, probably linked to the first one. Mar 18 '16 at 7:44
  • Will specify that this is about QGIS.
    – ragnvald
    Mar 18 '16 at 7:50
  • To my knowledge there is no way out of the box, to align point symbols to each other. I'm happy to be wrong. Last time I had the problem, it was handled in a desktop publishing tool like Illustrator.
    – Jakob
    Mar 18 '16 at 9:03

You can achieve the following using some expression-based SVG symbols.

enter image description here

Basically, you'd have multiple attributes that determine icon #1, #2, and so on.

enter image description here

As far as I know, it is currently not possible to make the SVG location depend on the corresponding label location though. So you'll want to avoid placing labels in the lower right corner, a setting for this is available in 2.14.

Use offsets to move the icons to the correct location. The icon is defined based on the attribute value:

enter image description here

  • Since not all icons allways are used one could get gaps in the lineup of icons, right?
    – ragnvald
    Mar 20 '16 at 22:24
  • 1
    No, that's not a problem with this approach. I added a screenshot of the attribute table to clarify.
    – underdark
    Mar 20 '16 at 22:56
  • I was thinking of maybe using an FTL-tool like FME to prepare the POI-clusters according to a distance buffer. By keeping an aggregated field/list of the poi within a cluster I could then use this list to add relevant icons together using Imagemagick linking them to a POI-production table. An other one could be to generate all possible mermutations of icons (up to say 6 icons width) and then use a key to call the relevant ones as PNGs or SVG-markers. A combination of your solution ant proper data preparation is probably best. Your answer is in the lead ;-)
    – ragnvald
    Mar 21 '16 at 20:02
  • Filtering based on one atttibute using "wildcards" instead of one attribute per icon could be better. Is it possible?
    – ragnvald
    Mar 21 '16 at 20:23
  • Probably but seems considerably more difficult.
    – underdark
    Mar 21 '16 at 20:54

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