Thanks Paolo for your replies here and at qt bugs report

In fact I am porting a qt widget application based on QGraphicsScene to QML and indeed these painting features are badly missing. Calculating polygon/shapes screen coordinates is not an issue in itself but that will become really tricky to implement when the users pans or zoom, so I would say unless I can do it through mapboxgl I will have to propose something else than dashed areas and lines.

There are some other features which I think will be missing too, for instance lines are just "loxodromic" (rhumb) lines, when they should be "orthodromic" (great circle), or at least there should be an option for both cases. Another big issue is the projection. Mercator is OK in most cases but is there a way to have another projection (with mapboxgl maybe ?), for instance Lambert conformal conic projection for usage in high latitudes?

That being said Qt Location is much much better that QGraphicsScene for doing all that stuff, of course.

Thanks again,
Philippe Lelong


Le 26-02-2019 15:21, Paolo Angelelli a écrit :
If you need dashed or dotted or styled lines, at the moment that's the
only workaround we can offer.
The built-in lines are using QTriangulatingStroker under the hood,
that seems to be missing that part
of the QPen features (brush, style).

as for map polygon, the only workaround i can think of, if mapboxgl
does not offer it/is not an option, is
to use a MapQuickItem instead, create the polygon with Shapes, and
then do the math and georeference it "manually".

As for your last question, i don't think i can answer since too many
details are missing

hope this helps a bit, anyway



On Mon, 25 Feb 2019 20:01:17 +0100
maitai <mai...@virtual-winds.org> wrote:

Hi,

I may be wrong since it seems incredible, but it seems there is no way
to draw a MapPolyLine dashed or dotlined, and similarly I didn't find a
way to fill a MapPolygon with a pattern.

If that is the case, what in your opinion would be the best way to
implement this?

I found QTBUG-46651 which recommends to use an empty mapboxgl layer
instead of my current itemsoverlay map, would that cover the needs since I have plenty of other mapItems and need to manage z values for each of
them?

Thanks
Philippe Lelong.
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