Loading Kml in a Qt application

CesiumJS
1

I created a test Qt application (Qt 5.3) to simply load the facilities sample kml file using a QWebView, as soon as the data is loaded navigation/moving the globe slows down drastically. Removing the loaded kml and the globe is back to moving smoothly. Has anyone been able to load kml data without the non responsiveness?

I also created a test Qt application (Qt 5.4) using QWebEngineView and received the error that while my browser supports WebGL Cesium failed to initialize. Using the QWebEngineView, I went to https://get.webgl.org/ and got the following: “While your browser seems to support WebGL, it is disabled or unavailable.” I attempted to use 5.4 in an effort to see if the responsiveness would be affected or not but was not able to get to the point of loading a kml file.

Any help/info would be appreciated.

2

Cesium’s integration with Qt is not official so we’ve not really dealt with any integration issues thus far.

Do you know what browser Qt is using?

3

Here’s a wiki page for Qt’s webkit WebKit - Wikipedia
I converted a project specific kml files and into czml files (several points and polylines with several coordinates) and loaded them using

viewer.dataSources.add(new Cesium.CzmlDataSource.load(‘http://path/to/the/file.czml’));

while the responsiveness is better than it would be if it were a kml file, it’s still a little choppy. Once the data is loaded, zooming in on any of the objects gives the error:

4

Is it possible to replicate this using the Sandcastle instead of with Qt? Sandcastle is built using the unminified version so if it fails you’ll get a more helpful error message.

5

I can’t get Sandcastle to read my “local” files (using node.js) so for now I don’t know if the error would be replicated.

6

Are you running the Node.js server from the Cesium package download.

7

Yes, that is correct.

8

You could put the kml files into Cesium directory and it would be accessable, or if you need to keep it say on a remote drive you could use a Python SimpleHTMLServer for that drive and can then link to it as though it’s on a network instead of a local file system. FYI if you go the Python simple html server route you’re probably going to need to use the default Proxy with your datasource configuration because the port numbers will not match between the Node server and the Python server