gdal slow rendering when zoomed in fix

git-svn-id: http://svn.osgeo.org/qgis/trunk@15702 c8812cc2-4d05-0410-92ff-de0c093fc19c
qgis · Apr 15, 2011 · a4659dd · a4659dd
1 parent eb3a535
commit a4659dd
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/src/providers/gdal/qgsgdalprovider.cpp b/src/providers/gdal/qgsgdalprovider.cpp
@@ -691,10 +691,11 @@ void QgsGdalProvider::readBlock( int theBandNo, QgsRectangle  const & theExtent,
   {
     tmpWidth = static_cast<int>( qRound( srcWidth * srcXRes / xRes ) ) ;
   }
-  if ( yRes > srcYRes )
+  if ( yRes > fabs( srcYRes ) )
   {
     tmpHeight = static_cast<int>( qRound( -1.*srcHeight * srcYRes / yRes ) ) ;
   }
+
   double tmpXMin = mExtent.xMinimum() + srcLeft * srcXRes;
   double tmpYMax = mExtent.yMaximum() + srcTop * srcYRes;
   QgsDebugMsg( QString( "tmpXMin = %1 tmpYMax = %2 tmpWidth = %3 tmpHeight = %4" ).arg( tmpXMin ).arg( tmpYMax ).arg( tmpWidth ).arg( tmpHeight ) );