Qwt-Moving Map with S-57/63 Charts and Shapefiles. Suggestions needed.

[swamyonline]

Kind Attention: Mr. Uwe.

Hi friends,
I am having a Qt5 based application in which I use Qwt6 for plotting data (points and symbols - total not more than 2000). My requirement is to add a moving map (S-57/ 63 Charts, shapefile based) to that application and overlay the data (those points and symbols) on it with zooming and panning facility.

My question is: Should I use Qwt controls or Qt's GraphicsView Widgets for implementing this. And also, I am new to handling S-57/63 charts, do they need any extra libraries for drawing them on Qt/ Qwt widgets? Is Qt/ Qwt sufficient for implementing this? Please put some light on this issue.

Question for Mr. Uwe: In an earlier post, you have talked about Qwt based GIS application.

I've written a complete GIS application with Qwt, so displaying a map should be possible too. How to do it depends on the type of data you want to display. So how does the data of your map looks like ?

Is your GIS application open source or proprietary? If it is open source, can you please share it with our Qt users? What I mean to ask this question is to why to re-invent the wheel.

Thanks in advance.

swamy.

[Uwe]

I am having a Qt5 based application in which I use Qwt6 for plotting data (points and symbols - total not more than 2000). My requirement is to add a moving map (S-57/ 63 Charts, shapefile based) to that application and overlay the data (those points and symbols) on it with zooming and panning facility.

Don't know about S-57/ 63 - is this about vector data only or does it include raster data as well ?

Is your GIS application open source or proprietary?

See: http://www.pegaware.com/products/pegaplan/features.html. All 2D graphics were done with Qwt.

Uwe

[swamyonline]

Hi,
Thanks Mr.Uwe for your prompt reply.

Don't know about S-57/ 63 - is this about vector data only or does it include raster data as well ?

Yes, S-57/ S-63 (Electronic Navigational Charts) format contains vector data only and it is supported by a standardization file mentioning the rules (symbology and colorization) of how and what to plot. My main interest was to know whether any extra libraries are required to read those charts' data and draw it on a widget.
Thanks for your response once again.


swamy.

[ianynchen]

Theoretically speaking, yes you can do that. But S-57 chart data content and its presentation rules are much more complicated than simply displaying them. There is actually a whole set of rules related to how they should be represented, called S-52. S-63 is much simpler though. It's no more than a set of S-57 files encrypted using blowfish. I've been working on S-57 display engines using Qt since Qt4

If you are simply interested in reading S-57 without worrying too much about its topology or contents, GDAL/OGR should do just fine. But reading into OGR format loses S-57 topology and will hence affect the way how S-57 charts are displayed, and will make it S-52 non-compatible. Plus, OGR does not actually read out the features and attributes ie, convert strings to doubles etc. The performance is only mediocore IMHO

[swamyonline]

Hi Ianynchen,
Thanks for your reply. Its not only simply reading S-57 but it is also required to draw it in a Qt application window as well as drawing an over lay of points, lines, symbols etc on the that map. I will come back to you as on when I need help in this regard. Thanks again for your response.

swamy