Updated renderNorthArrow slot to receive and draw to the qpainter pointer passed by the mapcanvas::renderComplete signal. This allows the north arrow plugin to draw onto the map even when it is being rendered to a device other than the mapCanvas' own pixmap member.

git-svn-id: http://svn.osgeo.org/qgis/trunk@1502 c8812cc2-4d05-0410-92ff-de0c093fc19c

plugins/north_arrow/plugin.cpp

@@ -66,9 +66,9 @@ static const QgisPlugin::PLUGINTYPE type_ = QgisPlugin::UI;
  * @param _qI Pointer to the QGIS interface object
  */
 Plugin::Plugin(QgisApp * theQGisApp, QgisIface * theQgisInterFace):
-qgisMainWindowPointer(theQGisApp), 
+    qgisMainWindowPointer(theQGisApp),
     qGisInterface(theQgisInterFace),
-QgisPlugin(name_,description_,version_,type_)
+    QgisPlugin(name_,description_,version_,type_)
 {
   mRotationInt=0;
   mPlacement=tr("Bottom Left");
@@ -76,7 +76,6 @@ QgisPlugin(name_,description_,version_,type_)
 
 Plugin::~Plugin()
 {
-
 }
 
 /*
@@ -97,7 +96,7 @@ void Plugin::initGui()
   // Connect the action to the run
   connect(myQActionPointer, SIGNAL(activated()), this, SLOT(run()));
   //render the arrow each time the map is rendered
-  connect(qGisInterface->getMapCanvas(), SIGNAL(renderComplete()), this, SLOT(renderNorthArrow()));
+  connect(qGisInterface->getMapCanvas(), SIGNAL(renderComplete(QPainter *)), this, SLOT(renderNorthArrow(QPainter *)));
   // Add the toolbar
   toolBarPointer = new QToolBar((QMainWindow *) qgisMainWindowPointer, "Decorations");
   toolBarPointer->setLabel("North Arrow");
@@ -134,26 +133,25 @@ void Plugin::refreshCanvas()
   qGisInterface->getMapCanvas()->refresh();
 }
 
-void Plugin::renderNorthArrow()
+void Plugin::renderNorthArrow(QPainter * theQPainter)
-{
-
-//Large IF statement controlled by enable check box
-if (mEnable)
 {
+#ifdef QGISDEBUG
+      std::cout << "Rendering n-arrow"  << std::endl;
+#endif
+  //Large IF statement controlled by enable check box
+  if (mEnable)
+  {
     QPixmap myQPixmap; //to store the north arrow image in
     QString myFileNameQString = QString(PKGDATAPATH) +
                                 QString("/images/north_arrows/default.png");
     //std::cout << "Trying to load " << myFileNameQString << std::cout;
     if (myQPixmap.load(myFileNameQString))
     {
-    // myPainterPixmap.fill();
-    QPainter myQPainter;
-    myQPainter.begin(qGisInterface->getMapCanvas()->canvasPixmap());	
 
       double centerXDouble = myQPixmap.width()/2;
       double centerYDouble = myQPixmap.height()/2;
       //save the current canvas rotation
-    myQPainter.save();
+      theQPainter->save();
       //
       //work out how to shift the image so that it rotates
       //           properly about its center
@@ -180,46 +178,41 @@ if (mEnable)
       //Determine placement of label from form combo box
       if (mPlacement==tr("Bottom Left"))
       {
-      myQPainter.translate(0,myHeight-myQPixmap.height());	
+        theQPainter->translate(0,myHeight-myQPixmap.height());
       }
       else if (mPlacement==tr("Top Right"))
       {
-      myQPainter.translate(myWidth-myQPixmap.width(),0);	
+        theQPainter->translate(myWidth-myQPixmap.width(),0);
       }
       else if (mPlacement==tr("Bottom Right"))
       {
-      myQPainter.translate(myWidth-myQPixmap.width(),
+        theQPainter->translate(myWidth-myQPixmap.width(),
                              myHeight-myQPixmap.height());
       }
       else // defaulting to top left
       {
         //no need to translate for TL corner because we're already at the origin
-      myQPainter.translate(0, 0); 
+        theQPainter->translate(0, 0);
       }
       //rotate the canvas by the north arrow rotation amount
-    myQPainter.rotate( mRotationInt );
+      theQPainter->rotate( mRotationInt );
       //Now we can actually do the drawing
-    myQPainter.drawPixmap(xShift,yShift,myQPixmap);	
+      theQPainter->drawPixmap(xShift,yShift,myQPixmap);
 
       //unrotate the canvase again
-    myQPainter.restore();
+      theQPainter->restore();
-    myQPainter.end();
 
       //bitBlt ( qGisInterface->getMapCanvas()->canvasPixmap(), 0, 0, &myPainterPixmap, 0, 0, -1 , -1, Qt::CopyROP, false);
 
     }
     else
     {
-    //myPainterPixmap.fill();
-    QPainter myQPainter;
-    myQPainter.begin(qGisInterface->getMapCanvas()->canvasPixmap());	
       QFont myQFont("time", 32, QFont::Bold);
-    myQPainter.setFont(myQFont);
+      theQPainter->setFont(myQFont);
-    myQPainter.setPen(Qt::black);
+      theQPainter->setPen(Qt::black);
-    myQPainter.drawText(10, 20, QString("Pixmap Not Found"));
+      theQPainter->drawText(10, 20, QString("Pixmap Not Found"));
-    myQPainter.end();
+    }
   }
-}
 
 }
 // Unload the plugin by cleaning up the GUI

plugins/north_arrow/plugin.h

@@ -21,6 +21,8 @@
 #define PLUGIN
 #include "../qgisplugin.h"
 #include <qwidget.h>
+#include <qpainter.h>
+
 
 #include "../../src/qgisapp.h"
 
@@ -47,7 +49,7 @@ class Plugin:public QObject, public QgisPlugin
   //! Show the dialog box
   void run();
   // draw some arbitary text to the screen
-  void renderNorthArrow();
+  void renderNorthArrow(QPainter *);
   //! Run when the user has set a new rotation
   void rotationChanged(int);
   //! Refresh the map display using the mapcanvas exported via the plugin interface