QGIS » QGIS Application

In windows the measure tool is pretty much unusable, it's very slow and glitches a lot.

Looking at the debug log a lot of calls are made to setEllisoid(). Each time the mouse moves this is printed.

r45184 d:\\src\\qgis\\src\\core\\qgsdistancearea.cpp(161) : (QgsDistanceArea::setEllipsoid) setEllipsoid: a=6.37814e+06, b=6.37814e+06, 1/f=298.257
r45184 d:\\src\\qgis\\src\\core\\qgscoordinatereferencesystem.cpp(349) : (QgsCoordinateReferenceSystem::createFromProj4) proj4: +proj=longlat +ellps=WGS84 +no_defs
r45184 d:\\src\\qgis\\src\\core\\qgscoordinatereferencesystem.cpp(378) : (QgsCoordinateReferenceSystem::createFromProj4) proj string supplied has no +a argument
r45184 d:\\src\\qgis\\src\\core\\qgscoordinatereferencesystem.cpp(540) : (QgsCoordinateReferenceSystem::getRecord) running query: select * from tbl_srs where parameters='+proj=longlat +ellps=WGS84 +no_defs'
r45184 d:\\src\\qgis\\src\\core\\qgscoordinatereferencesystem.cpp(562) : (QgsCoordinateReferenceSystem::getRecord) trying system srs.db
r45184 d:\\src\\qgis\\src\\core\\qgscoordinatereferencesystem.cpp(617) : (QgsCoordinateReferenceSystem::getRecord) retrieved:  select * from tbl_srs where parameters='+proj=longlat +ellps=WGS84 +no_defs'
r45184 d:\\src\\qgis\\src\\core\\qgscoordinatereferencesystem.cpp(406) : (QgsCoordinateReferenceSystem::createFromProj4) proj4string match search for srsid returned srsid: 3239
r45184 d:\\src\\qgis\\src\\core\\qgscoordinatereferencesystem.cpp(799) : (QgsCoordinateReferenceSystem::setMapUnits) Projection has linear units of Meter
r45184 d:\\src\\qgis\\src\\core\\qgscoordinatereferencesystem.cpp(799) : (QgsCoordinateReferenceSystem::setMapUnits) Projection has linear units of Meter

Tracked down to this bit of code:

void [[QgsMeasureDialog]]::configureDistanceArea( [[QgsDistanceArea]]& da )
{
  QSettings settings;
  QString ellipsoidId = settings.value( "/qgis/measure/ellipsoid", "WGS84" ).toString();
  da.setSourceCrs( mTool->canvas()->mapRenderer()->destinationCrs().srsid() );
  da.setEllipsoid( ellipsoidId );
  da.setProjectionsEnabled( mcbProjectionEnabled->isChecked() );
}

Which is called on every mouse move. Do we really need to call it on every mouse move?