Implement drawing of ruler markers

Author: mhugent

src/app/composer/qgscomposer.cpp

@@ -526,20 +526,23 @@ void QgsComposer::zoomFull( void )
 void QgsComposer::on_mActionZoomAll_triggered()
 {
   zoomFull();
+  mView->updateRulers();
   mView->update();
   emit zoomLevelChanged();
 }
 
 void QgsComposer::on_mActionZoomIn_triggered()
 {
   mView->scale( 2, 2 );
+  mView->updateRulers();
   mView->update();
   emit zoomLevelChanged();
 }
 
 void QgsComposer::on_mActionZoomOut_triggered()
 {
   mView->scale( .5, .5 );
+  mView->updateRulers();
   mView->update();
   emit zoomLevelChanged();
 }

src/gui/qgscomposerruler.cpp

@@ -1,5 +1,6 @@
 #include "qgscomposerruler.h"
 #include <QPainter>
+#include <cmath>
 
 const int RULER_MIN_SIZE = 20;
 
@@ -19,8 +20,41 @@ QSize QgsComposerRuler::minimumSizeHint() const
 void QgsComposerRuler::paintEvent( QPaintEvent* event )
 {
   Q_UNUSED( event );
-
-  //draw blue rectangle for a test
   QPainter p( this );
-  p.fillRect( rect(), QColor( 0, 0, 255 ) );
+
+  QTransform t = mTransform.inverted();
+
+  if ( mDirection == Horizontal )
+  {
+    //start x-coordinate
+    double startX = t.map( QPointF( 0, 0 ) ).x();//-mTransform.dx() / mTransform.m11();
+    double endX = t.map( QPointF( width(), 0 ) ).x();//( -mTransform.dx() + width() ) / mTransform.m11();
+
+    double markerPos = ( floor( startX / 10.0 ) + 1 ) * 10.0 - RULER_MIN_SIZE; //marker position in mm
+    while ( markerPos <= endX )
+    {
+      if ( markerPos >= 0 && markerPos <= 296 ) //todo: need to know paper size
+      {
+        double pixelCoord = mTransform.map( QPointF( markerPos, 0 ) ).x();
+        p.drawLine( pixelCoord, 0, pixelCoord, RULER_MIN_SIZE );
+      }
+      markerPos += 10.0;
+    }
+
+    qWarning( QString::number( startX ).toLocal8Bit().data() );
+    qWarning( QString::number( endX ).toLocal8Bit().data() );
+  }
+  else //vertical
+  {
+    //p.fillRect( rect(), QColor( 0, 0, 255 ) );
+  }
+}
+
+void QgsComposerRuler::setSceneTransform( const QTransform& transform )
+{
+  QString debug = QString::number( transform.dx() ) + "," + QString::number( transform.dy() ) + ","
+                  + QString::number( transform.m11() ) + "," + QString::number( transform.m22() );
+  qWarning( debug.toLocal8Bit().data() );
+  mTransform = transform;
+  update();
 }

src/gui/qgscomposerruler.h

@@ -18,11 +18,14 @@ class QgsComposerRuler: public QWidget
 
     QSize minimumSizeHint() const;
 
+    void setSceneTransform( const QTransform& transform );
+
   protected:
     void paintEvent( QPaintEvent* event );
 
   private:
     Direction mDirection;
+    QTransform mTransform;
 };
 
 #endif // QGSCOMPOSERRULER_H

src/gui/qgscomposerview.cpp

@@ -256,6 +256,18 @@ void QgsComposerView::addShape( Tool currentTool )
   }
 }
 
+void QgsComposerView::updateRulers()
+{
+  if ( mHorizontalRuler )
+  {
+    mHorizontalRuler->setSceneTransform( viewportTransform() );
+  }
+  if ( mVerticalRuler )
+  {
+    mVerticalRuler->setSceneTransform( viewportTransform() );
+  }
+}
+
 void QgsComposerView::mouseReleaseEvent( QMouseEvent* e )
 {
   if ( !composition() )
@@ -627,6 +639,18 @@ void QgsComposerView::showEvent( QShowEvent* e )
   e->ignore();
 }
 
+void QgsComposerView::resizeEvent( QResizeEvent* event )
+{
+  QGraphicsView::resizeEvent( event );
+  updateRulers();
+}
+
+void QgsComposerView::scrollContentsBy( int dx, int dy )
+{
+  QGraphicsView::scrollContentsBy( dx, dy );
+  updateRulers();
+}
+
 void QgsComposerView::setComposition( QgsComposition* c )
 {
   setScene( c );

src/gui/qgscomposerview.h

@@ -90,6 +90,9 @@ class GUI_EXPORT QgsComposerView: public QGraphicsView
     void setPaintingEnabled( bool enabled ) { mPaintingEnabled = enabled; }
     bool paintingEnabled() const { return mPaintingEnabled; }
 
+    /**Update rulers with current scene rect*/
+    void updateRulers();
+
   protected:
     void mousePressEvent( QMouseEvent* );
     void mouseReleaseEvent( QMouseEvent* );
@@ -106,6 +109,9 @@ class GUI_EXPORT QgsComposerView: public QGraphicsView
     void hideEvent( QHideEvent* e );
     void showEvent( QShowEvent* e );
 
+    void resizeEvent( QResizeEvent* event );
+    void scrollContentsBy( int dx, int dy );
+
   private:
     /**Status of shift key (used for multiple selection)*/
     bool mShiftKeyPressed;