#9060: use QGis::fromUnitToUnitFactor in QgsDistanceArea

ahuarte47 · ahuarte47 · commit c20f38b6ba14 · 2014-01-14T20:53:06.000+01:00
in
diff --git a/src/core/qgsdistancearea.cpp b/src/core/qgsdistancearea.cpp
@@ -989,7 +989,7 @@ QString QgsDistanceArea::textUnit( double value, int decimals, QGis::UnitType u,
 
 void QgsDistanceArea::convertMeasurement( double &measure, QGis::UnitType &measureUnits, QGis::UnitType displayUnits, bool isArea )
 {
-  // Helper for converting between meters and feet
+  // Helper for converting between meters and feet and degrees and NauticalMiles...
   // The parameters measure and measureUnits are in/out
 
   if (( measureUnits == QGis::Degrees || measureUnits == QGis::Feet || measureUnits == QGis::NauticalMiles ) &&
@@ -1001,73 +1001,12 @@ void QgsDistanceArea::convertMeasurement( double &measure, QGis::UnitType &measu
     QgsDebugMsg( "We're measuring on an ellipsoid or using projections, the system is returning meters" );
   }
 
-  // Only convert between meters and feet
-  if ( measureUnits == QGis::Meters && displayUnits == QGis::Feet )
-  {
-    QgsDebugMsg( QString( "Converting %1 meters" ).arg( QString::number( measure ) ) );
-    measure /= 0.3048;
-    if ( isArea )
-    {
-      measure /= 0.3048;
-    }
-    QgsDebugMsg( QString( "to %1 feet" ).arg( QString::number( measure ) ) );
-    measureUnits = QGis::Feet;
-  }
-  if ( measureUnits == QGis::Feet && displayUnits == QGis::Meters )
-  {
-    QgsDebugMsg( QString( "Converting %1 feet" ).arg( QString::number( measure ) ) );
-    measure *= 0.3048;
-    if ( isArea )
-    {
-      measure *= 0.3048;
-    }
-    QgsDebugMsg( QString( "to %1 meters" ).arg( QString::number( measure ) ) );
-    measureUnits = QGis::Meters;
-  }
+  // Gets the conversion factor between the specified units
+  double factorUnits = QGis::fromUnitToUnitFactor( measureUnits, displayUnits );
+  if ( isArea ) factorUnits *= factorUnits;
 
-  if ( measureUnits == QGis::Meters && displayUnits == QGis::NauticalMiles )
-  {
-    QgsDebugMsg( QString( "Converting %1 meters" ).arg( QString::number( measure ) ) );
-    measure /= 1852.0;
-    if ( isArea )
-    {
-      measure /= 1852.0;
-    }
-    QgsDebugMsg( QString( "to %1 nautical miles" ).arg( QString::number( measure ) ) );
-    measureUnits = QGis::NauticalMiles;
-  }
-  if ( measureUnits == QGis::NauticalMiles && displayUnits == QGis::Meters )
-  {
-    QgsDebugMsg( QString( "Converting %1 nautical miles" ).arg( QString::number( measure ) ) );
-    measure *= 1852.0;
-    if ( isArea )
-    {
-      measure *= 1852.0;
-    }
-    QgsDebugMsg( QString( "to %1 meters" ).arg( QString::number( measure ) ) );
-    measureUnits = QGis::Meters;
-  }
-
-  if ( measureUnits == QGis::Feet && displayUnits == QGis::NauticalMiles )
-  {
-    QgsDebugMsg( QString( "Converting %1 meters" ).arg( QString::number( measure ) ) );
-    measure /= 6076.12;
-    if ( isArea )
-    {
-      measure /= 6076.12;
-    }
-    QgsDebugMsg( QString( "to %1 nautical miles" ).arg( QString::number( measure ) ) );
-    measureUnits = QGis::Feet;
-  }
-  if ( measureUnits == QGis::NauticalMiles && displayUnits == QGis::Feet )
-  {
-    QgsDebugMsg( QString( "Converting %1 nautical miles" ).arg( QString::number( measure ) ) );
-    measure *= 6076.12;
-    if ( isArea )
-    {
-      measure *= 6076.12;
-    }
-    QgsDebugMsg( QString( "to %1 meters" ).arg( QString::number( measure ) ) );
-    measureUnits = QGis::Feet;
-  }
+  QgsDebugMsg( QString( "Converting %1 %2" ).arg( QString::number( measure ), QGis::toLiteral( measureUnits ) ) );
+  measure *= factorUnits;
+  QgsDebugMsg( QString( "to %1 %2" ).arg( QString::number( measure ), QGis::toLiteral( displayUnits ) ) );
+  measureUnits = displayUnits;
 }
