JSON Parser error when loading TPK as an Elevation Source. QT WINDOWS 10

SPI_LLC_1

I been having issues loading a TPK file into my application for QT.  To start from a know quantity i used the MontereyElevation.tpk file that is in the examples.   https://developers.arcgis.com/qt/cpp/sample-code/create-terrain-surface-from-a-local-tile-package/

from the Example executables i could not run the file with a 3d topology.  Instead it displays a flat map.

 

in my own code samples i use the following lines:

-----------------------

const QString tile_elevation_package_path = QString{"d://temp/export/MontereyElevation.tpk"};

// Before attempting to add any layers, check that the file for the elevation source exists at all.
const bool src_elevation_file_exists = QFileInfo::exists(tile_elevation_package_path);

if(src_elevation_file_exists) {
qInfo() << "elevation source package found";
ArcGISTiledElevationSource* elevationsrc=new ArcGISTiledElevationSource{QUrl("file:"+tile_elevation_package_path), this};
// When the elevation source is finished loading, call the elevationSrcFinishedLoading callback, so we can tell if it loaded succesfully.
connect(elevationSrc, &ArcGISTiledElevationSource::doneLoading, this, &Add_layers_to_a_3d_scene::packageLoaded);

// add the elevation source to the scene to display elevation
m_scene->baseSurface()->elevationSources()->append(elevationSrc);
} else {
qInfo() << "elevation source file not found";
}

----------------------------------

 

void Add_layers_to_a_3d_scene::packageLoaded(const Error& e)
{
if (!e.isEmpty())
{
qDebug() << QString("Package load error: %1 %2").arg(e.message(), e.additionalMessage());
return;
}

}

 

the error code i receive:

"Package load error: JSON parser invalid start of JSON. Error processing service metadata response.\nP : 0"

 

I have experienced this same error with  my own LERC TPK generated from ARCGIS Pro.  

 

Thanks in advance!

 

 

Tanner_Yould

Hi @SPI_LLC_1, unfortunately I'm having trouble replicating your issue. Are you able to run the unmodified Create terrain surface from local tile package sample provided from our GitHub repo? You'll need to add the Monterey Elevation TPK to the file path like `<username>/ArcGIS/Runtime/Data/tpk/MontereyElevation.tpk`.

And also, just to double check, what version of Qt and version of ArcGIS Runtime are you using?

I'm thinking that either there's a problem on the back end with Qt or the Runtime API being out of date, or it's something to do with these lines of code where you load the file:

const QString tile_elevation_package_path = QString{"d://temp/export/MontereyElevation.tpk"};

ArcGISTiledElevationSource* elevationsrc=new ArcGISTiledElevationSource{QUrl("file:"+tile_elevation_package_path), this};

 

In our sample, we use the following syntax, but I confirmed that either works.

// CreateTerrainSurfaceFromLocalTilePackage.cpp

const QString montereyTileElevationPath = QString{defaultDataPath() + "/ArcGIS/Runtime/Data/tpk/MontereyElevation.tpk"}; // defaultDataPath() is defined on lines 39-52

ArcGISTiledElevationSource* elevationsrc=new ArcGISTiledElevationSource{montereyTileElevationPath, this};

 

Sorry I can't be of more help initially, but I'm hoping we can resolve this soon!

Thanks!

- Tanner