[FEATURE] Add option to georeference PDFs and TIFs to save map canvas…

… as image/PDF
qgis · Aug 12, 2019 · 2e4a567 · 2e4a567
1 parent c567974
commit 2e4a567
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Showing 10 changed files with 109 additions and 23 deletions.
diff --git a/python/core/auto_generated/qgsmaprenderertask.sip.in b/python/core/auto_generated/qgsmaprenderertask.sip.in
@@ -57,7 +57,7 @@ Adds ``decorations`` to be rendered on the map.
 
     void setSaveWorldFile( bool save );
 %Docstring
-Sets whether a world file will be created alongside an image file.
+Sets whether the image file will be georeferenced (embedded or via a world file).
 %End
 
     virtual void cancel();

diff --git a/python/core/auto_generated/qgsmapsettingsutils.sip.in b/python/core/auto_generated/qgsmapsettingsutils.sip.in
@@ -28,6 +28,20 @@ Utilities for map settings.
 Checks whether any of the layers attached to a map settings object contain advanced effects
 
 :param mapSettings: map settings
+%End
+
+    static void worldFileParameters( const QgsMapSettings &mapSettings, double &a /Out/, double &b /Out/, double &c /Out/, double &d /Out/, double &e /Out/, double &f /Out/ );
+%Docstring
+Computes the six parameters of a world file.
+
+:param mapSettings: map settings
+:param b: the b parameter
+:param c: the c parameter
+:param d: the d parameter
+:param e: the e parameter
+:param f: the f parameter
+
+.. versionadded:: 3.10
 %End
 
     static QString worldFileContent( const QgsMapSettings &mapSettings );

diff --git a/src/app/qgsmapsavedialog.cpp b/src/app/qgsmapsavedialog.cpp
@@ -95,8 +95,6 @@ QgsMapSaveDialog::QgsMapSaveDialog( QWidget *parent, QgsMapCanvas *mapCanvas, co
 
   if ( mDialogType == QgsMapSaveDialog::Pdf )
   {
-    mSaveWorldFile->setVisible( false );
-
     QStringList layers = QgsMapSettingsUtils::containsAdvancedEffects( mMapCanvas->mapSettings() );
     if ( !layers.isEmpty() )
     {

diff --git a/src/app/qgsmapsavedialog.h b/src/app/qgsmapsavedialog.h
@@ -71,7 +71,7 @@ class APP_EXPORT QgsMapSaveDialog: public QDialog, private Ui::QgsMapSaveDialog
     //! returns whether the draw decorations element is checked
     bool drawDecorations() const;
 
-    //! returns whether a world file will be created
+    //! returns whether the resulting image will be georeferenced (embedded or via world file)
     bool saveWorldFile() const;
 
     //! returns whether the map will be rasterized

diff --git a/src/core/qgsmaprenderertask.cpp b/src/core/qgsmaprenderertask.cpp
@@ -19,11 +19,15 @@
 #include "qgsannotationmanager.h"
 #include "qgsmaprenderertask.h"
 #include "qgsmapsettingsutils.h"
-
+#include "qgsogrutils.h"
+#include "qgslogger.h"
 #include <QFile>
 #include <QTextStream>
 #include <QPrinter>
 
+#include "gdal.h"
+#include "cpl_conv.h"
+
 QgsMapRendererTask::QgsMapRendererTask( const QgsMapSettings &ms, const QString &fileName, const QString &fileFormat, const bool forceRaster )
   : QgsTask( tr( "Saving as image" ) )
   , mMapSettings( ms )
@@ -86,7 +90,8 @@ bool QgsMapRendererTask::run()
     printer->setOutputFormat( QPrinter::PdfFormat );
     printer->setOrientation( QPrinter::Portrait );
     // paper size needs to be given in millimeters in order to be able to set a resolution to pass onto the map renderer
-    printer->setPaperSize( mMapSettings.outputSize()  * 25.4 / mMapSettings.outputDpi(), QPrinter::Millimeter );
+    QSizeF outputSize = mMapSettings.outputSize();
+    printer->setPaperSize( outputSize  * 25.4 / mMapSettings.outputDpi(), QPrinter::Millimeter );
     printer->setPageMargins( 0, 0, 0, 0, QPrinter::Millimeter );
     printer->setResolution( mMapSettings.outputDpi() );
 
@@ -190,6 +195,25 @@ bool QgsMapRendererTask::run()
       QRectF rect( 0, 0, img.width(), img.height() );
       pp.drawImage( rect, img, rect );
       pp.end();
+
+      if ( mSaveWorldFile )
+      {
+        CPLSetThreadLocalConfigOption( "GDAL_PDF_DPI", QString::number( mMapSettings.outputDpi() ).toLocal8Bit().constData() );
+        gdal::dataset_unique_ptr outputDS( GDALOpen( mFileName.toLocal8Bit().constData(), GA_Update ) );
+        if ( outputDS )
+        {
+          double a, b, c, d, e, f;
+          QgsMapSettingsUtils::worldFileParameters( mMapSettings, a, b, c, d, e, f );
+          c -= 0.5 * a;
+          c -= 0.5 * b;
+          f -= 0.5 * d;
+          f -= 0.5 * e;
+          double geoTransform[6] = { c, a, b, f, d, e };
+          GDALSetGeoTransform( outputDS.get(), geoTransform );
+          GDALSetProjection( outputDS.get(), mMapSettings.destinationCrs().toWkt().toLocal8Bit().constData() );
+        }
+        CPLSetThreadLocalConfigOption( "GDAL_PDF_DPI", nullptr );
+      }
 #else
       mError = ImageUnsupportedFormat;
       return false;
@@ -210,14 +234,36 @@ bool QgsMapRendererTask::run()
 
         // build the world file name
         QString outputSuffix = info.suffix();
-        QString worldFileName = info.absolutePath() + '/' + info.baseName() + '.'
-                                + outputSuffix.at( 0 ) + outputSuffix.at( info.suffix().size() - 1 ) + 'w';
-        QFile worldFile( worldFileName );
+        bool skipWorldFile = false;
+        if ( outputSuffix == QStringLiteral( "tif" ) || outputSuffix == QStringLiteral( "tiff" ) )
+        {
+          gdal::dataset_unique_ptr outputDS( GDALOpen( mFileName.toLocal8Bit().constData(), GA_Update ) );
+          if ( outputDS )
+          {
+            skipWorldFile = true;
+            double a, b, c, d, e, f;
+            QgsMapSettingsUtils::worldFileParameters( mMapSettings, a, b, c, d, e, f );
+            c -= 0.5 * a;
+            c -= 0.5 * b;
+            f -= 0.5 * d;
+            f -= 0.5 * e;
+            double geoTransform[] = { c, a, b, f, d, e };
+            GDALSetGeoTransform( outputDS.get(), geoTransform );
+            GDALSetProjection( outputDS.get(), mMapSettings.destinationCrs().toWkt().toLocal8Bit().constData() );
+          }
+        }
 
-        if ( worldFile.open( QIODevice::WriteOnly | QIODevice::Truncate ) ) //don't use QIODevice::Text
+        if ( !skipWorldFile )
         {
-          QTextStream stream( &worldFile );
-          stream << QgsMapSettingsUtils::worldFileContent( mMapSettings );
+          QString worldFileName = info.absolutePath() + '/' + info.baseName() + '.'
+                                  + outputSuffix.at( 0 ) + outputSuffix.at( info.suffix().size() - 1 ) + 'w';
+          QFile worldFile( worldFileName );
+
+          if ( worldFile.open( QIODevice::WriteOnly | QIODevice::Truncate ) ) //don't use QIODevice::Text
+          {
+            QTextStream stream( &worldFile );
+            stream << QgsMapSettingsUtils::worldFileContent( mMapSettings );
+          }
         }
       }
     }

diff --git a/src/core/qgsmaprenderertask.h b/src/core/qgsmaprenderertask.h
@@ -76,7 +76,7 @@ class CORE_EXPORT QgsMapRendererTask : public QgsTask
     void addDecorations( const QList<QgsMapDecoration *> &decorations );
 
     /**
-     * Sets whether a world file will be created alongside an image file.
+     * Sets whether the image file will be georeferenced (embedded or via a world file).
      */
     void setSaveWorldFile( bool save ) { mSaveWorldFile = save; }
 

diff --git a/src/core/qgsmapsettingsutils.cpp b/src/core/qgsmapsettingsutils.cpp
@@ -66,7 +66,7 @@ const QStringList QgsMapSettingsUtils::containsAdvancedEffects( const QgsMapSett
   return layers.toList();
 }
 
-QString QgsMapSettingsUtils::worldFileContent( const QgsMapSettings &mapSettings )
+void QgsMapSettingsUtils::worldFileParameters( const QgsMapSettings &mapSettings, double &a, double &b, double &c, double &d, double &e, double &f )
 {
   QgsMapSettings ms = mapSettings;
 
@@ -101,14 +101,20 @@ QString QgsMapSettingsUtils::worldFileContent( const QgsMapSettings &mapSettings
   r[5] = - xCenter * std::sin( alpha ) + yCenter * ( 1 - std::cos( alpha ) );
 
   // result = rotation x scaling = rotation(scaling(X))
-  double a = r[0] * s[0] + r[1] * s[3];
-  double b = r[0] * s[1] + r[1] * s[4];
-  double c = r[0] * s[2] + r[1] * s[5] + r[2];
-  double d = r[3] * s[0] + r[4] * s[3];
+  a = r[0] * s[0] + r[1] * s[3];
+  b = r[0] * s[1] + r[1] * s[4];
+  c = r[0] * s[2] + r[1] * s[5] + r[2];
+  d = r[3] * s[0] + r[4] * s[3];
   // Pixel YDim - almost always negative
   // See https://en.wikipedia.org/wiki/World_file#cite_ref-3, https://github.com/qgis/QGIS/issues/26379
-  double e =  r[3] * s[1] + r[4] * s[4];
-  double f = r[3] * s[2] + r[4] * s[5] + r[5];
+  e = r[3] * s[1] + r[4] * s[4];
+  f = r[3] * s[2] + r[4] * s[5] + r[5];
+}
+
+QString QgsMapSettingsUtils::worldFileContent( const QgsMapSettings &mapSettings )
+{
+  double a, b, c, d, e, f;
+  worldFileParameters( mapSettings, a, b, c, d, e, f );
 
   QString content;
   // Pixel XDim
@@ -119,9 +125,9 @@ QString QgsMapSettingsUtils::worldFileContent( const QgsMapSettings &mapSettings
   content += qgsDoubleToString( b ) + "\r\n";
   // Pixel YDim
   content += qgsDoubleToString( e ) + "\r\n";
-  // Origin X (center of top left cell)
+  // Origin X (top left cell)
   content += qgsDoubleToString( c ) + "\r\n";
-  // Origin Y (center of top left cell)
+  // Origin Y (top left cell)
   content += qgsDoubleToString( f ) + "\r\n";
 
   return content;

diff --git a/src/core/qgsmapsettingsutils.h b/src/core/qgsmapsettingsutils.h
@@ -39,6 +39,19 @@ class CORE_EXPORT QgsMapSettingsUtils
      */
     static const QStringList containsAdvancedEffects( const QgsMapSettings &mapSettings );
 
+    /**
+     * Computes the six parameters of a world file.
+     * \param mapSettings map settings
+     * \param a the a parameter
+     * \param b the b parameter
+     * \param c the c parameter
+     * \param d the d parameter
+     * \param e the e parameter
+     * \param f the f parameter
+     * \since QGIS 3.10
+     */
+    static void worldFileParameters( const QgsMapSettings &mapSettings, double &a SIP_OUT, double &b SIP_OUT, double &c SIP_OUT, double &d SIP_OUT, double &e SIP_OUT, double &f SIP_OUT );
+
     /**
      * Creates the content of a world file.
      * \param mapSettings map settings

diff --git a/src/ui/qgsmapsavedialog.ui b/src/ui/qgsmapsavedialog.ui
@@ -43,7 +43,7 @@ Rasterizing the map is recommended when such effects are used.</string>
      <item row="7" column="0" colspan="2">
       <widget class="QCheckBox" name="mSaveWorldFile">
        <property name="text">
-        <string>Save world file</string>
+        <string>Append georeference information (embedded or via world file)</string>
        </property>
        <property name="checked">
         <bool>true</bool>

diff --git a/tests/src/core/testqgsmapsettingsutils.cpp b/tests/src/core/testqgsmapsettingsutils.cpp
@@ -48,6 +48,15 @@ void TestQgsMapSettingsUtils::initTestCase()
 
 void TestQgsMapSettingsUtils::createWorldFileContent()
 {
+  double a, b, c, d, e, f;
+  QgsMapSettingsUtils::worldFileParameters( mMapSettings, a, b, c, d, e, f );
+  QCOMPARE( a, 1.0 );
+  QCOMPARE( b, 0.0 );
+  QCOMPARE( c, 0.5 );
+  QCOMPARE( d, 0.0 );
+  QCOMPARE( e, -1.0 );
+  QCOMPARE( f, 0.5 );
+
   QCOMPARE( QgsMapSettingsUtils::worldFileContent( mMapSettings ), QString( "1\r\n0\r\n0\r\n-1\r\n0.5\r\n0.5\r\n" ) );
 
   mMapSettings.setRotation( 45 );