Good afternoon,
I am developing a QGIS application in C++ and am looking to overlay weather
data stored in NetCDF files as mesh layers. Each file has several variables
that can be displayed; however it only displays one variable or dataset (always
the first one in alphabetical order) and I'm not sure how to make it so I can
choose which variable I want displayed. For an entire layer I know I can call
the layer tree node like this:
QString layerName = "Temperature";
QgsLayerTree *tree = project->instance()->layerTreeRoot(); //project is
QgsProject object
for ( QgsMapLayer *layer: qmc->layers() ) // qmc is QgsMapCanvas object
QgsLayerTreeNode *node = tree->findLayer(layer->id());
if ( layer->name() == layerName )
{
node->setItemVisibilityChecked(true);
} else
{
node->setItemVisibilityChecked(false);
}
}
but its parallel for Mesh Layer subsets doesn't work:
QgsMeshLayer *mesh = new QgsMeshLayer("/path/to/file.nc","MyData","mdal");
QString dataName = "Temperature";
for ( int &i: mesh->datasetGroupsIndexes() )
{
QgsMeshDatasetIndex did = i;
QgsMeshDatasetGroupTreeItem *child = tree->childFromDatasetGroupIndex(i);
if ( child->name() == dataName )
{
child->setIsEnabled(true);
} else
{
child->setIsEnabled(false);
}
}
I've also tried to set the layer rendering for datasets, but it seems to
pertain to the entire file (mesh->datasetGroupCount > mesh->datasetCount; the
renderer only pertains to the dataset (count = 1). This would be helpful to
figure out as setting the renderer for different types of data (vectors for
wind, contours for pressure, etc) is the end goal of this application, and
would be an upgrade from having to create multiple shapefiles/rasters for this
data. There doesn't seem to be many examples out there for mesh layer use
outside of the QGIS console, not even for PyQGIS developers.
Brian
_______________________________________________
QGIS-Developer mailing list
[email protected]
List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer
Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer
