Make bar width configurable

src/app/qgsvectorlayerproperties.cpp

@@ -900,6 +900,8 @@ void QgsVectorLayerProperties::apply()
       ds.diagramOrientation = QgsDiagramSettings::Left;
     }
 
+    ds.barWidth = mBarWidthSpinBox->value();
+
     if ( mFixedSizeCheckBox->isChecked() )
     {
       QgsSingleCategoryDiagramRenderer* dr = new QgsSingleCategoryDiagramRenderer();
@@ -1748,9 +1750,10 @@ void QgsVectorLayerProperties::initDiagramTab()
         case QgsDiagramSettings::Down:
           mOrientationDownButton->setChecked( true );
           break;
-
       }
 
+      mBarWidthSpinBox->setValue( settingList.at( 0 ).barWidth );
+
       mIncreaseSmallDiagramsCheckBox->setChecked( settingList.at( 0 ).minimumSize != 0 );
       mIncreaseMinimumSizeSpinBox->setValue( settingList.at( 0 ).minimumSize );
 

src/core/qgsdiagram.cpp

@@ -351,7 +351,8 @@ void QgsHistogramDiagram::renderDiagram( const QgsAttributeMap& att, QgsRenderCo
     values.push_back( currentVal );
   }
 
-  double currentOffset = 0;
+  double currentOffset = 0 - ( values.size() * s.barWidth ) / 2;
+  double scaledWidth = sizePainterUnits( s.barWidth, s, c );
 
   double baseX = position.x();
   double baseY = position.y();
@@ -360,8 +361,6 @@ void QgsHistogramDiagram::renderDiagram( const QgsAttributeMap& att, QgsRenderCo
   setPenWidth( mPen, s, c );
   p->setPen( mPen );
 
-  p->drawPoint( baseX, baseY );
-
   QList<double>::const_iterator valIt = values.constBegin();
   QList< QColor >::const_iterator colIt = s.categoryColors.constBegin();
   for ( ; valIt != values.constEnd(); ++valIt, ++colIt )
@@ -374,22 +373,22 @@ void QgsHistogramDiagram::renderDiagram( const QgsAttributeMap& att, QgsRenderCo
     switch ( s.diagramOrientation )
     {
     case QgsDiagramSettings::Up:
-        p->drawRect( baseX + currentOffset, baseY, 10, 0 - length );
+        p->drawRect( baseX + currentOffset, baseY, scaledWidth, 0 - length );
         break;
 
       case QgsDiagramSettings::Down:
-        p->drawRect( baseX + currentOffset, baseY, 10, length );
+        p->drawRect( baseX + currentOffset, baseY, scaledWidth, length );
         break;
 
       case QgsDiagramSettings::Right:
-        p->drawRect( baseX, baseY + currentOffset, 0 - length, 10 );
+        p->drawRect( baseX, baseY + currentOffset, 0 - length, scaledWidth );
         break;
 
       case QgsDiagramSettings::Left:
-        p->drawRect( baseX, baseY + currentOffset, length, 10 );
+        p->drawRect( baseX, baseY + currentOffset, length, scaledWidth );
         break;
     }
 
-    currentOffset += 10;
+    currentOffset += scaledWidth;
   }
 }

src/core/qgsdiagramrendererv2.cpp

@@ -93,6 +93,8 @@ void QgsDiagramSettings::readXML( const QDomElement& elem )
     diagramOrientation = Up;
   }
 
+  barWidth = elem.attribute( "barWidth" ).toDouble();
+
   minimumSize = elem.attribute( "minimumSize" ).toDouble();
 
   //colors
@@ -170,6 +172,7 @@ void QgsDiagramSettings::writeXML( QDomElement& rendererElem, QDomDocument& doc
       break;
   }
 
+  categoryElem.setAttribute( "barWidth", QString::number( barWidth ) );
   categoryElem.setAttribute( "minimumSize", QString::number( minimumSize ) );
 
   QString colors;

src/core/qgsdiagramrendererv2.h

@@ -123,6 +123,7 @@ struct CORE_EXPORT QgsDiagramSettings
   double penWidth;
   LabelPlacementMethod labelPlacementMethod;
   DiagramOrientation diagramOrientation;
+  double barWidth;
 
   //scale range (-1 if no lower / upper bound )
   double minScaleDenominator;

src/ui/qgsvectorlayerpropertiesbase.ui

@@ -1353,6 +1353,20 @@
                 </property>
                </spacer>
               </item>
+              <item row="6" column="0" colspan="3">
+               <layout class="QHBoxLayout" name="mBarWidthLayout">
+                <item>
+                 <widget class="QLabel" name="label_6">
+                  <property name="text">
+                   <string>Bar width</string>
+                  </property>
+                 </widget>
+                </item>
+                <item>
+                 <widget class="QDoubleSpinBox" name="mBarWidthSpinBox"/>
+                </item>
+               </layout>
+              </item>
              </layout>
             </widget>
            </item>