Simplify tool: show status message about the simplification results

qgis · Jan 22, 2015 · 0f9e1f7 · 0f9e1f7
1 parent 4322de9
commit 0f9e1f7
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Showing 3 changed files with 77 additions and 26 deletions.
diff --git a/src/app/qgsmaptoolsimplify.cpp b/src/app/qgsmaptoolsimplify.cpp
@@ -43,6 +43,11 @@ QgsSimplifyDialog::QgsSimplifyDialog( QgsMapToolSimplify* tool, QWidget* parent
 
 }
 
+void QgsSimplifyDialog::updateStatusText()
+{
+  labelStatus->setText( mTool->statusText() );
+}
+
 
 ////////////////////////////////////////////////////////////////////////////
 
@@ -51,6 +56,8 @@ QgsMapToolSimplify::QgsMapToolSimplify( QgsMapCanvas* canvas )
     : QgsMapToolEdit( canvas )
     , mSelectionRubberBand( 0 )
     , mDragging( false )
+    , mOriginalVertexCount( 0 )
+    , mReducedVertexCount( 0 )
 {
   QSettings settings;
   mTolerance = settings.value( "/digitizing/simplify_tolerance", 1 ).toDouble();
@@ -92,15 +99,40 @@ void QgsMapToolSimplify::updateSimplificationPreview()
 {
   QgsVectorLayer* vl = currentVectorLayer();
 
+  mReducedVertexCount = 0;
   int i = 0;
   foreach ( const QgsFeature& fSel, mSelectedFeatures )
   {
     // create a copy of selected feature and do the simplification
     QgsFeature f = fSel;
     QgsSimplifyFeature::simplify( f, mTolerance, mToleranceUnits, mCanvas->mapSettings().layerTransform( vl ) );
+    mReducedVertexCount += vertexCount( f.geometry() );
     mRubberBands[i]->setToGeometry( f.geometry(), vl );
     ++i;
   }
+
+  mSimplifyDialog->updateStatusText();
+}
+
+
+int QgsMapToolSimplify::vertexCount( QgsGeometry* g ) const
+{
+  switch ( g->type() )
+  {
+    case QGis::Line:
+    {
+      return g->asPolyline().count();
+    }
+    case QGis::Polygon:
+    {
+      int count = 0;
+      foreach ( const QgsPolyline& ring, g->asPolygon() )
+        count += ring.count();
+      return count;
+    }
+    default:
+      return 0;
+  }
 }
 
 
@@ -292,10 +324,12 @@ void QgsMapToolSimplify::canvasReleaseEvent( QMouseEvent * e )
 
   mDragging = false;
 
-  // prepare rubber bands
+  // count vertices, prepare rubber bands
+  mOriginalVertexCount = 0;
   foreach ( const QgsFeature& f, mSelectedFeatures )
   {
-    Q_UNUSED( f );
+    mOriginalVertexCount += vertexCount( f.geometry() );
+
     QgsRubberBand* rb = new QgsRubberBand( mCanvas );
     rb->setColor( QColor( 255, 0, 0, 65 ) );
     rb->setWidth( 2 );
@@ -384,6 +418,13 @@ void QgsMapToolSimplify::deactivate()
   QgsMapTool::deactivate();
 }
 
+QString QgsMapToolSimplify::statusText() const
+{
+  int percent = mOriginalVertexCount ? ( 100 * mReducedVertexCount / mOriginalVertexCount ) : 0;
+  return tr( "%1 feature(s): %2 to %3 vertices (%4%)" )
+         .arg( mSelectedFeatures.count() ).arg( mOriginalVertexCount ).arg( mReducedVertexCount ).arg( percent );
+}
+
 
 QVector<QgsPoint> QgsMapToolSimplify::getPointList( QgsFeature& f )
 {

diff --git a/src/app/qgsmaptoolsimplify.h b/src/app/qgsmaptoolsimplify.h
@@ -34,11 +34,11 @@ class APP_EXPORT QgsSimplifyDialog : public QDialog, private Ui::SimplifyLineDia
 
     QgsSimplifyDialog( QgsMapToolSimplify* tool, QWidget* parent = NULL );
 
+    void updateStatusText();
+
   private:
     QgsMapToolSimplify* mTool;
 
-  private slots:
-
 };
 
 
@@ -63,6 +63,8 @@ class APP_EXPORT QgsMapToolSimplify: public QgsMapToolEdit
 
     ToleranceUnits toleranceUnits() const { return mToleranceUnits; }
 
+    QString statusText() const;
+
   public slots:
     /** slot to change display when slidebar is moved */
     void setTolerance( double tolerance );
@@ -81,6 +83,8 @@ class APP_EXPORT QgsMapToolSimplify: public QgsMapToolEdit
 
     void updateSimplificationPreview();
 
+    int vertexCount( QgsGeometry* g ) const;
+
     /** Function to calculate tolerance boudaries for simplifying */
     //bool calculateSliderBoudaries();
 
@@ -107,6 +111,9 @@ class APP_EXPORT QgsMapToolSimplify: public QgsMapToolEdit
     QgsRubberBand* mSelectionRubberBand;
     //! Flag to indicate a map canvas drag operation is taking place
     bool mDragging;
+
+    int mOriginalVertexCount;
+    int mReducedVertexCount;
 };
 
 /**

diff --git a/src/ui/qgssimplifytolerancedialog.ui b/src/ui/qgssimplifytolerancedialog.ui
@@ -7,34 +7,21 @@
     <x>0</x>
     <y>0</y>
     <width>527</width>
-    <height>38</height>
+    <height>63</height>
    </rect>
   </property>
   <property name="windowTitle">
    <string>Simplification Tool</string>
   </property>
-  <layout class="QHBoxLayout">
-   <item>
-    <widget class="QLabel" name="label">
+  <layout class="QGridLayout" name="gridLayout">
+   <item row="0" column="3">
+    <widget class="QPushButton" name="okButton">
      <property name="text">
-      <string>Tolerance</string>
-     </property>
-    </widget>
-   </item>
-   <item>
-    <widget class="QDoubleSpinBox" name="spinTolerance">
-     <property name="decimals">
-      <number>6</number>
-     </property>
-     <property name="maximum">
-      <double>999999.000000000000000</double>
-     </property>
-     <property name="value">
-      <double>1.000000000000000</double>
+      <string>OK</string>
      </property>
     </widget>
    </item>
-   <item>
+   <item row="0" column="2">
     <widget class="QComboBox" name="cboToleranceUnits">
      <item>
       <property name="text">
@@ -48,13 +35,29 @@
      </item>
     </widget>
    </item>
-   <item>
-    <widget class="QPushButton" name="okButton">
+   <item row="0" column="0">
+    <widget class="QLabel" name="label">
      <property name="text">
-      <string>OK</string>
+      <string>Tolerance</string>
+     </property>
+    </widget>
+   </item>
+   <item row="0" column="1">
+    <widget class="QDoubleSpinBox" name="spinTolerance">
+     <property name="decimals">
+      <number>6</number>
+     </property>
+     <property name="maximum">
+      <double>999999.000000000000000</double>
+     </property>
+     <property name="value">
+      <double>1.000000000000000</double>
      </property>
     </widget>
    </item>
+   <item row="1" column="0" colspan="4">
+    <widget class="QLabel" name="labelStatus"/>
+   </item>
   </layout>
  </widget>
  <tabstops>