Ensure extent is updated when QgsExtentGroupBox crs is changed

qgis · May 31, 2017 · e2de69d · e2de69d
1 parent 5649c40
commit e2de69d
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Showing 5 changed files with 41 additions and 5 deletions.
diff --git a/python/gui/qgsextentgroupbox.sip b/python/gui/qgsextentgroupbox.sip
@@ -87,10 +87,12 @@ class QgsExtentGroupBox : QgsCollapsibleGroupBox
  :rtype: QgsCoordinateReferenceSystem
 %End
 
-    void setOutputCrs( const QgsCoordinateReferenceSystem &outputCrs );
+    void setOutputCrs( const QgsCoordinateReferenceSystem &outputCrs, bool reprojectCurrentExtent = true );
 %Docstring
  Sets the output CRS - may need to be used for transformation from original/current extent.
  Should be called as part of initialization and whenever the the output CRS is changed.
+ If ``reprojectCurrentExtent`` is true then the current extent will be reproject into the
+ new output CRS.
 %End
 
     QgsRectangle outputExtent() const;

diff --git a/src/gui/qgsextentgroupbox.cpp b/src/gui/qgsextentgroupbox.cpp
@@ -61,12 +61,27 @@ void QgsExtentGroupBox::setCurrentExtent( const QgsRectangle &currentExtent, con
   mCurrentCrs = currentCrs;
 }
 
-void QgsExtentGroupBox::setOutputCrs( const QgsCoordinateReferenceSystem &outputCrs )
+void QgsExtentGroupBox::setOutputCrs( const QgsCoordinateReferenceSystem &outputCrs, bool reprojectCurrentExtent )
 {
+  if ( reprojectCurrentExtent && mOutputCrs != outputCrs )
+  {
+    try
+    {
+      QgsCoordinateTransform ct( mOutputCrs, outputCrs );
+      QgsRectangle extent = ct.transformBoundingBox( outputExtent() );
+      mXMinLineEdit->setText( QgsRasterBlock::printValue( extent.xMinimum() ) );
+      mXMaxLineEdit->setText( QgsRasterBlock::printValue( extent.xMaximum() ) );
+      mYMinLineEdit->setText( QgsRasterBlock::printValue( extent.yMinimum() ) );
+      mYMaxLineEdit->setText( QgsRasterBlock::printValue( extent.yMaximum() ) );
+    }
+    catch ( QgsCsException & )
+    {
+      // can't reproject
+    }
+  }
   mOutputCrs = outputCrs;
 }
 
-
 void QgsExtentGroupBox::setOutputExtent( const QgsRectangle &r, const QgsCoordinateReferenceSystem &srcCrs, ExtentState state )
 {
   QgsRectangle extent;

diff --git a/src/gui/qgsextentgroupbox.h b/src/gui/qgsextentgroupbox.h
@@ -104,8 +104,10 @@ class GUI_EXPORT QgsExtentGroupBox : public QgsCollapsibleGroupBox, private Ui::
     /**
      * Sets the output CRS - may need to be used for transformation from original/current extent.
      * Should be called as part of initialization and whenever the the output CRS is changed.
+     * If \a reprojectCurrentExtent is true then the current extent will be reproject into the
+     * new output CRS.
      */
-    void setOutputCrs( const QgsCoordinateReferenceSystem &outputCrs );
+    void setOutputCrs( const QgsCoordinateReferenceSystem &outputCrs, bool reprojectCurrentExtent = true );
 
     /**
      * Returns the extent shown in the widget - in output CRS coordinates.

diff --git a/src/gui/qgsrasterlayersaveasdialog.cpp b/src/gui/qgsrasterlayersaveasdialog.cpp
@@ -435,7 +435,7 @@ void QgsRasterLayerSaveAsDialog::crsChanged()
 {
   if ( outputCrs() != mPreviousCrs )
   {
-    mExtentGroupBox->setOutputCrs( outputCrs() );
+    mExtentGroupBox->setOutputCrs( outputCrs(), false );
     QgsExtentGroupBox::ExtentState state = mExtentGroupBox->extentState();
 
     // Reset extent

diff --git a/tests/src/python/test_qgsextentgroupbox.py b/tests/src/python/test_qgsextentgroupbox.py
@@ -82,6 +82,23 @@ def test_SettingExtent(self):
         self.assertEqual(w.extentState(), QgsExtentGroupBox.ProjectLayerExtent)
         self.assertEqual(len(spy), 4)
 
+    def testSetOutputCrs(self):
+        w = qgis.gui.QgsExtentGroupBox()
+
+        w.setOutputCrs(QgsCoordinateReferenceSystem('epsg:4326'))
+        w.setCurrentExtent(QgsRectangle(1, 2, 3, 4), QgsCoordinateReferenceSystem('epsg:4326'))
+        w.setOutputExtentFromCurrent()
+        self.assertEqual(w.outputExtent(), QgsRectangle(1, 2, 3, 4))
+
+        # no reprojection
+        w.setOutputCrs(QgsCoordinateReferenceSystem('epsg:3785'), False)
+        self.assertEqual(w.outputExtent(), QgsRectangle(1, 2, 3, 4))
+        w.setOutputCrs(QgsCoordinateReferenceSystem('epsg:4326'), False)
+
+        # with reprojection
+        w.setOutputCrs(QgsCoordinateReferenceSystem('epsg:3785'), True)
+        self.assertEqual(w.outputExtent().toString(4), QgsRectangle(111319.4908, 222684.2085, 333958.4724, 445640.1097).toString(4))
+
 
 if __name__ == '__main__':
     unittest.main()