Geotagged image support needs major facelift

[FranciscoDS]

I was opening an issue about compiling with the GEOIMAGE=1 parameter but I've seen this was fixed with commit e6d015a953a163.

Still there is a "lack of documentation" in the INSTALL file, it doesn't talk of the required parameter GEOIMAGE=1 (and of course the exiv2 development libs) for the geotagged photo support, only the CHANGELOG file mention it.

There is also a warning which could be a potential bug in GeoImageDock.cpp.

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Docks/GeoImageDock.cpp: In member function ‘bool GeoImageDock::getWalkingPapersDetails(const QUrl&, double&, double&, bool&) const’: Docks/GeoImageDock.cpp:84:20: warning: logical not is only applied to the left hand side of comparison [-Wlogical-not-parentheses] if (!sl.size() == 3) ^ Docks/GeoImageDock.cpp:84:20: warning: comparison of constant ‘3’ with boolean expression is always false [-Wbool-compare]

[Krakonos]

Thanks for reporting. I actually think the GEOIMAGE stuff was never finished, or I don't know how it's supposed to work.

I will work on it soon, as I have a lot of geotagged photos from my trip, and I want to use them for mapping.

[Krakonos]

So I looked at it today. Here is what I have found:

• You can't import geoimages using "Import" (which is intuitive)
• You can open geoimages using "Open" (which isn't intuitive)
• You can't import geoimages on commandline, as it won't recognize the tags (I don't know why)
• The correlation function doesn't work at all.
• If you happen to get it working, it kind-of-sort-of does something, and shows you images on the map and son on, but nothing fancy.

I will have to think about the user interface, as it's practicaly non-existent, and do a serious rewrite.

Also, there is a Walking Papers feature built into that. I have no idea if it works, and I won't bother to try. If someone uses it, please, create an issue for it, and I'll examine it & provide support somewhere outside geoimages, as I want to keep it for geotagged images only.

Let me know if you have ideas on the UI and/or features, I'll start working on it as soon as 0.18.3 is out.

[FranciscoDS]

To give some insight, my current workflow is :

• correlate photo before launching merkaartor (I didn't like the UI and I prefer doing it manually)
• File -> Open to load the already geotagged photo
• File -> Import to load the GPX track (sometime I didn't bother loading the original GPS track as the photo is all it's needed and they are already on map)
• Download the area
• Interacting with the geotagged photo : click on photo on the canvas or cycle through the photo with PgUp, PgDown, C (to center the view), I use a lot the latter just to be sure to use all the photos, I also have to zoom a lot on the geotagged dock (I haven't a multi-screen system)

I also have a big issue with the geotagged dock, when you select a node the photo disappear. But it work fine when you select a way : you can edit the way and still see the photo at the same time.

I've used the correlation function a few years ago, I remember I've got a small success : the gps track must be loaded before but I've got the offset in the wrong direction. Anyway, I stick to pre-correlate outside merkaartor.

I can't help with the Walking Papers, I have tried it but never understood how it is supposed to work and never have any success running it.

Finally I've never quite understood why there is a distinction between File Load and File Import, it's probably better to have :

• File -> New start with a clean, new, blank slate
• File -> Load import data (mdc, gpx, photo or whatever) into a new layer

I didn't remember if in the earlier version there was this distinction but for me it doesn't make sense. This is a small but different issue, so probably best to open a new github issue on this one and have other users comment on it as it can be a disruptive change.

[Krakonos]

Thanks! I'm thinking the same thing about the geoimages.

Walking Papers are supposed to be printed, drawn upon outdoors, without gps, scan them later and use them as image layer. Since the ractangle is encoded in the printout, it can be as accurate as you can draw on a piece of paper. I think people rarely use it today, although I know of at least one recent case that used this or similar feature, and they didn't use Merkaartor, but iD (I think).

Open is equivalent to New & Import; at least in my mind.