bool QgsMapToolIdentify::identifyRasterLayer( QList<IdentifyResult> *results, QgsRasterLayer *layer, QgsPoint point, const QgsRectangle& viewExtent, double mapUnitsPerPixel )
{
QgsDebugMsg( "point = " + point.toString() );
if ( !layer )
return false;
QgsRasterDataProvider *dprovider = layer->dataProvider();
if ( !dprovider )
return false;
int capabilities = dprovider->capabilities();
if ( !( capabilities & QgsRasterDataProvider::Identify ) )
return false;
QgsPoint pointInCanvasCrs = point;
try
{
point = toLayerCoordinates( layer, point );
}
catch ( QgsCsException &cse )
{
Q_UNUSED( cse );
QgsDebugMsg( QString( "coordinate not reprojectable: %1" ).arg( cse.what() ) );
return false;
}
QgsDebugMsg( QString( "point = %1 %2" ).arg( point.x() ).arg( point.y() ) );
if ( !layer->extent().contains( point ) )
return false;
QMap< QString, QString > attributes, derivedAttributes;
QgsRaster::IdentifyFormat format = QgsRasterDataProvider::identifyFormatFromName( layer->customProperty( "identify/format" ).toString() );
// check if the format is really supported otherwise use first supported format
if ( !( QgsRasterDataProvider::identifyFormatToCapability( format ) & capabilities ) )
{
if ( capabilities & QgsRasterInterface::IdentifyFeature ) format = QgsRaster::IdentifyFormatFeature;
else if ( capabilities & QgsRasterInterface::IdentifyValue ) format = QgsRaster::IdentifyFormatValue;
else if ( capabilities & QgsRasterInterface::IdentifyHtml ) format = QgsRaster::IdentifyFormatHtml;
else if ( capabilities & QgsRasterInterface::IdentifyText ) format = QgsRaster::IdentifyFormatText;
else return false;
}
QgsRasterIdentifyResult identifyResult;
// We can only use current map canvas context (extent, width, height) if layer is not reprojected,
if ( mCanvas->hasCrsTransformEnabled() && dprovider->crs() != mCanvas->mapSettings().destinationCrs() )
{
// To get some reasonable response for point/line WMS vector layers we must
// use a context with approximately a resolution in layer CRS units
// corresponding to current map canvas resolution (for examplei UMN Mapserver
// in msWMSFeatureInfo() -> msQueryByRect() is using requested pixel
// + TOLERANCE (layer param) for feature selection)
//
QgsRectangle r;
r.setXMinimum( pointInCanvasCrs.x() - mapUnitsPerPixel / 2. );
r.setXMaximum( pointInCanvasCrs.x() + mapUnitsPerPixel / 2. );
r.setYMinimum( pointInCanvasCrs.y() - mapUnitsPerPixel / 2. );
r.setYMaximum( pointInCanvasCrs.y() + mapUnitsPerPixel / 2. );
r = toLayerCoordinates( layer, r ); // will be a bit larger
// Mapserver (6.0.3, for example) does not work with 1x1 pixel box
// but that is fixed (the rect is enlarged) in the WMS provider
identifyResult = dprovider->identify( point, format, r, 1, 1 );
}
else
{
// It would be nice to use the same extent and size which was used for drawing,
// so that WCS can use cache from last draw, unfortunately QgsRasterLayer::draw()
// is doing some tricks with extent and size to allign raster to output which
// would be difficult to replicate here.
// Note: cutting the extent may result in slightly different x and y resolutions
// and thus shifted point calculated back in QGIS WMS (using average resolution)
//viewExtent = dprovider->extent().intersect( &viewExtent );
// Width and height are calculated from not projected extent and we hope that
// are similar to source width and height used to reproject layer for drawing.
// TODO: may be very dangerous, because it may result in different resolutions
// in source CRS, and WMS server (QGIS server) calcs wrong coor using average resolution.
int width = qRound( viewExtent.width() / mapUnitsPerPixel );
int height = qRound( viewExtent.height() / mapUnitsPerPixel );
QgsDebugMsg( QString( "viewExtent.width = %1 viewExtent.height = %2" ).arg( viewExtent.width() ).arg( viewExtent.height() ) );
QgsDebugMsg( QString( "width = %1 height = %2" ).arg( width ).arg( height ) );
QgsDebugMsg( QString( "xRes = %1 yRes = %2 mapUnitsPerPixel = %3" ).arg( viewExtent.width() / width ).arg( viewExtent.height() / height ).arg( mapUnitsPerPixel ) );
identifyResult = dprovider->identify( point, format, viewExtent, width, height );
}
derivedAttributes.insert( tr( "(clicked coordinate)" ), point.toString() );
if ( identifyResult.isValid() )
{
QMap<int, QVariant> values = identifyResult.results();
QgsGeometry geometry;
if ( format == QgsRaster::IdentifyFormatValue )
{
Q_FOREACH ( int bandNo, values.keys() )
{
QString valueString;
if ( values.value( bandNo ).isNull() )
{
valueString = tr( "no data" );
}
else
{
double value = values.value( bandNo ).toDouble();
valueString = QgsRasterBlock::printValue( value );
}
attributes.insert( dprovider->generateBandName( bandNo ), valueString );
}
QString label = layer->name();
results->append( IdentifyResult( qobject_cast<QgsMapLayer *>( layer ), label, attributes, derivedAttributes ) );
}
bool QgsMapToolIdentify::identifyRasterLayer( QList<IdentifyResult> *results, QgsRasterLayer *layer, QgsPointXY point, const QgsRectangle &viewExtent, double mapUnitsPerPixel )
{
QgsDebugMsg( "point = " + point.toString() );
if ( !layer )
return false;
QgsRasterDataProvider *dprovider = layer->dataProvider();
if ( !dprovider )
return false;
int capabilities = dprovider->capabilities();
if ( !( capabilities & QgsRasterDataProvider::Identify ) )
return false;
QgsPointXY pointInCanvasCrs = point;
try
{
point = toLayerCoordinates( layer, point );
}
catch ( QgsCsException &cse )
{
Q_UNUSED( cse );
QgsDebugMsg( QString( "coordinate not reprojectable: %1" ).arg( cse.what() ) );
return false;
}
QgsDebugMsg( QString( "point = %1 %2" ).arg( point.x() ).arg( point.y() ) );
if ( !layer->extent().contains( point ) )
return false;
QMap< QString, QString > attributes, derivedAttributes;
QgsRaster::IdentifyFormat format = QgsRasterDataProvider::identifyFormatFromName( layer->customProperty( QStringLiteral( "identify/format" ) ).toString() );
// check if the format is really supported otherwise use first supported format
if ( !( QgsRasterDataProvider::identifyFormatToCapability( format ) & capabilities ) )
{
if ( capabilities & QgsRasterInterface::IdentifyFeature ) format = QgsRaster::IdentifyFormatFeature;
else if ( capabilities & QgsRasterInterface::IdentifyValue ) format = QgsRaster::IdentifyFormatValue;
else if ( capabilities & QgsRasterInterface::IdentifyHtml ) format = QgsRaster::IdentifyFormatHtml;
else if ( capabilities & QgsRasterInterface::IdentifyText ) format = QgsRaster::IdentifyFormatText;
else return false;
}
QgsRasterIdentifyResult identifyResult;
// We can only use current map canvas context (extent, width, height) if layer is not reprojected,
if ( dprovider->crs() != mCanvas->mapSettings().destinationCrs() )
{
// To get some reasonable response for point/line WMS vector layers we must
// use a context with approximately a resolution in layer CRS units
// corresponding to current map canvas resolution (for examplei UMN Mapserver
// in msWMSFeatureInfo() -> msQueryByRect() is using requested pixel
// + TOLERANCE (layer param) for feature selection)
//
QgsRectangle r;
r.setXMinimum( pointInCanvasCrs.x() - mapUnitsPerPixel / 2. );
r.setXMaximum( pointInCanvasCrs.x() + mapUnitsPerPixel / 2. );
r.setYMinimum( pointInCanvasCrs.y() - mapUnitsPerPixel / 2. );
r.setYMaximum( pointInCanvasCrs.y() + mapUnitsPerPixel / 2. );
r = toLayerCoordinates( layer, r ); // will be a bit larger
// Mapserver (6.0.3, for example) does not work with 1x1 pixel box
// but that is fixed (the rect is enlarged) in the WMS provider
identifyResult = dprovider->identify( point, format, r, 1, 1 );
}
else
{
// It would be nice to use the same extent and size which was used for drawing,
// so that WCS can use cache from last draw, unfortunately QgsRasterLayer::draw()
// is doing some tricks with extent and size to align raster to output which
// would be difficult to replicate here.
// Note: cutting the extent may result in slightly different x and y resolutions
// and thus shifted point calculated back in QGIS WMS (using average resolution)
//viewExtent = dprovider->extent().intersect( &viewExtent );
// Width and height are calculated from not projected extent and we hope that
// are similar to source width and height used to reproject layer for drawing.
// TODO: may be very dangerous, because it may result in different resolutions
// in source CRS, and WMS server (QGIS server) calcs wrong coor using average resolution.
int width = std::round( viewExtent.width() / mapUnitsPerPixel );
int height = std::round( viewExtent.height() / mapUnitsPerPixel );
QgsDebugMsg( QString( "viewExtent.width = %1 viewExtent.height = %2" ).arg( viewExtent.width() ).arg( viewExtent.height() ) );
QgsDebugMsg( QString( "width = %1 height = %2" ).arg( width ).arg( height ) );
QgsDebugMsg( QString( "xRes = %1 yRes = %2 mapUnitsPerPixel = %3" ).arg( viewExtent.width() / width ).arg( viewExtent.height() / height ).arg( mapUnitsPerPixel ) );
identifyResult = dprovider->identify( point, format, viewExtent, width, height );
}
derivedAttributes.insert( tr( "(clicked coordinate X)" ), formatXCoordinate( pointInCanvasCrs ) );
derivedAttributes.insert( tr( "(clicked coordinate Y)" ), formatYCoordinate( pointInCanvasCrs ) );
if ( identifyResult.isValid() )
{
QMap<int, QVariant> values = identifyResult.results();
QgsGeometry geometry;
if ( format == QgsRaster::IdentifyFormatValue )
{
for ( auto it = values.constBegin(); it != values.constEnd(); ++it )
{
QString valueString;
if ( it.value().isNull() )
{
valueString = tr( "no data" );
}
else
{
QVariant value( it.value() );
// The cast is legit. Quoting QT doc :
// "Although this function is declared as returning QVariant::Type,
// the return value should be interpreted as QMetaType::Type"
if ( static_cast<QMetaType::Type>( value.type() ) == QMetaType::Float )
{
valueString = QgsRasterBlock::printValue( value.toFloat() );
}
else
{
valueString = QgsRasterBlock::printValue( value.toDouble() );
}
}
attributes.insert( dprovider->generateBandName( it.key() ), valueString );
}
QString label = layer->name();
results->append( IdentifyResult( qobject_cast<QgsMapLayer *>( layer ), label, attributes, derivedAttributes ) );
}
else if ( format == QgsRaster::IdentifyFormatFeature )
{
for ( auto it = values.constBegin(); it != values.constEnd(); ++it )
{
QVariant value = it.value();
if ( value.type() == QVariant::Bool && !value.toBool() )
{
// sublayer not visible or not queryable
continue;
}
if ( value.type() == QVariant::String )
{
// error
// TODO: better error reporting
QString label = layer->subLayers().value( it.key() );
attributes.clear();
attributes.insert( tr( "Error" ), value.toString() );
results->append( IdentifyResult( qobject_cast<QgsMapLayer *>( layer ), label, attributes, derivedAttributes ) );
continue;
}
// list of feature stores for a single sublayer
const QgsFeatureStoreList featureStoreList = it.value().value<QgsFeatureStoreList>();
for ( const QgsFeatureStore &featureStore : featureStoreList )
{
const QgsFeatureList storeFeatures = featureStore.features();
for ( QgsFeature feature : storeFeatures )
{
attributes.clear();
// WMS sublayer and feature type, a sublayer may contain multiple feature types.
// Sublayer name may be the same as layer name and feature type name
// may be the same as sublayer. We try to avoid duplicities in label.
QString sublayer = featureStore.params().value( QStringLiteral( "sublayer" ) ).toString();
QString featureType = featureStore.params().value( QStringLiteral( "featureType" ) ).toString();
// Strip UMN MapServer '_feature'
featureType.remove( QStringLiteral( "_feature" ) );
QStringList labels;
if ( sublayer.compare( layer->name(), Qt::CaseInsensitive ) != 0 )
{
labels << sublayer;
}
if ( featureType.compare( sublayer, Qt::CaseInsensitive ) != 0 || labels.isEmpty() )
{
labels << featureType;
}
QMap< QString, QString > derAttributes = derivedAttributes;
derAttributes.unite( featureDerivedAttributes( &feature, layer ) );
IdentifyResult identifyResult( qobject_cast<QgsMapLayer *>( layer ), labels.join( QStringLiteral( " / " ) ), featureStore.fields(), feature, derAttributes );
identifyResult.mParams.insert( QStringLiteral( "getFeatureInfoUrl" ), featureStore.params().value( QStringLiteral( "getFeatureInfoUrl" ) ) );
results->append( identifyResult );
}
}
}
}
else // text or html
{
QgsDebugMsg( QString( "%1 HTML or text values" ).arg( values.size() ) );
for ( auto it = values.constBegin(); it != values.constEnd(); ++it )
{
QString value = it.value().toString();
attributes.clear();
attributes.insert( QLatin1String( "" ), value );
QString label = layer->subLayers().value( it.key() );
results->append( IdentifyResult( qobject_cast<QgsMapLayer *>( layer ), label, attributes, derivedAttributes ) );
}
}
}
else
{
attributes.clear();
QString value = identifyResult.error().message( QgsErrorMessage::Text );
attributes.insert( tr( "Error" ), value );
QString label = tr( "Identify error" );
results->append( IdentifyResult( qobject_cast<QgsMapLayer *>( layer ), label, attributes, derivedAttributes ) );
}
return true;
}