QgsMapCanvasTracer::QgsMapCanvasTracer( QgsMapCanvas *canvas, QgsMessageBar *messageBar )
: mCanvas( canvas )
, mMessageBar( messageBar )
{
sTracers.insert( canvas, this );
// when things change we just invalidate the graph - and set up new parameters again only when necessary
connect( canvas, &QgsMapCanvas::destinationCrsChanged, this, &QgsMapCanvasTracer::invalidateGraph );
connect( canvas, &QgsMapCanvas::layersChanged, this, &QgsMapCanvasTracer::invalidateGraph );
connect( canvas, &QgsMapCanvas::extentsChanged, this, &QgsMapCanvasTracer::invalidateGraph );
connect( canvas, &QgsMapCanvas::currentLayerChanged, this, &QgsMapCanvasTracer::onCurrentLayerChanged );
connect( canvas->snappingUtils(), &QgsSnappingUtils::configChanged, this, &QgsMapCanvasTracer::invalidateGraph );
// arbitrarily chosen limit that should allow for fairly fast initialization
// of the underlying graph structure
setMaxFeatureCount( QgsSettings().value( QStringLiteral( "/qgis/digitizing/tracing_max_feature_count" ), 10000 ).toInt() );
}
QgsMapCanvasTracer::QgsMapCanvasTracer( QgsMapCanvas* canvas, QgsMessageBar* messageBar )
: mCanvas( canvas )
, mMessageBar( messageBar )
, mLastMessage( nullptr )
, mActionEnableTracing( nullptr )
{
sTracers.insert( canvas, this );
// when things change we just invalidate the graph - and set up new parameters again only when necessary
connect( canvas, SIGNAL( destinationCrsChanged() ), this, SLOT( invalidateGraph() ) );
connect( canvas, SIGNAL( layersChanged() ), this, SLOT( invalidateGraph() ) );
connect( canvas, SIGNAL( extentsChanged() ), this, SLOT( invalidateGraph() ) );
connect( canvas, SIGNAL( currentLayerChanged( QgsMapLayer* ) ), this, SLOT( onCurrentLayerChanged() ) );
connect( canvas->snappingUtils(), SIGNAL( configChanged() ), this, SLOT( invalidateGraph() ) );
// arbitrarily chosen limit that should allow for fairly fast initialization
// of the underlying graph structure
setMaxFeatureCount( QSettings().value( "/qgis/digitizing/tracing_max_feature_count", 10000 ).toInt() );
}