From 20570bfa3e8b5206cc116499dc5bdd09155c8693 Mon Sep 17 00:00:00 2001
From: Martin Dobias <wonder.sk@gmail.com>
Date: Thu, 19 Jun 2014 15:48:19 +0700
Subject: [PATCH] Feeling dizzy?

It will not get any better if you type "dizzy"
into coordinates box in the status bar!
---
 src/app/qgisapp.cpp | 30 ++++++++++++++++++++++++++++++
 src/app/qgisapp.h   |  6 ++++++
 2 files changed, 36 insertions(+)

diff --git a/src/app/qgisapp.cpp b/src/app/qgisapp.cpp
index ca319e500fe..54a12df9970 100644
--- a/src/app/qgisapp.cpp
+++ b/src/app/qgisapp.cpp
@@ -1724,6 +1724,8 @@ void QgisApp::createStatusBar()
   mCoordsEdit->setToolTip( tr( "Current map coordinate (lat,lon or east,north)" ) );
   statusBar()->addPermanentWidget( mCoordsEdit, 0 );
   connect( mCoordsEdit, SIGNAL( returnPressed() ), this, SLOT( userCenter() ) );
+  mDizzyTimer = new QTimer( this );
+  connect( mDizzyTimer, SIGNAL( timeout() ), this, SLOT( dizzy() ) );
 
   // add a label to show current scale
   mScaleLabel = new QLabel( QString(), statusBar() );
@@ -6605,8 +6607,36 @@ void QgisApp::userScale()
   mMapCanvas->zoomScale( 1.0 / mScaleEdit->scale() );
 }
 
+void QgisApp::dizzy()
+{
+  // constants should go to options so that people can customize them to their taste
+  int d = 10; // max. translational dizziness offset
+  int r = 4;  // max. rotational dizzines angle
+  QRectF rect = mMapCanvas->sceneRect();
+  if ( rect.x() < -d || rect.x() > d || rect.y() < -d || rect.y() > d )
+    return; // do not affect panning
+  rect.moveTo(( rand() % ( 2 * d ) ) - d, ( rand() % ( 2 * d ) ) - d );
+  mMapCanvas->setSceneRect( rect );
+  QTransform matrix;
+  matrix.rotate(( rand() % ( 2 * r ) ) - r );
+  mMapCanvas->setTransform( matrix );
+}
+
 void QgisApp::userCenter()
 {
+  if ( mCoordsEdit->text() == "dizzy" )
+  {
+    // sometimes you may feel a bit dizzy...
+    if ( mDizzyTimer->isActive() )
+    {
+      mDizzyTimer->stop();
+      mMapCanvas->setSceneRect( mMapCanvas->viewport()->rect() );
+      mMapCanvas->setTransform( QTransform() );
+    }
+    else
+      mDizzyTimer->start( 100 );
+  }
+
   QStringList parts = mCoordsEdit->text().split( ',' );
   if ( parts.size() != 2 )
     return;
diff --git a/src/app/qgisapp.h b/src/app/qgisapp.h
index e9039877055..f01e6b6d4c5 100755
--- a/src/app/qgisapp.h
+++ b/src/app/qgisapp.h
@@ -1230,6 +1230,9 @@ class APP_EXPORT QgisApp : public QMainWindow, private Ui::MainWindow
      * @note added in 2.3 */
     void activateDeuteranopePreview();
 
+    /** Make the user feel dizzy */
+    void dizzy();
+
   signals:
     /** emitted when a key is pressed and we want non widget sublasses to be able
       to pick up on this (e.g. maplayer) */
@@ -1542,6 +1545,9 @@ class APP_EXPORT QgisApp : public QMainWindow, private Ui::MainWindow
      */
     QTimer *mpMapTipsTimer;
 
+    //! Helps to make people dizzy
+    QTimer* mDizzyTimer;
+
     /** Point of last mouse position in map coordinates (used with MapTips)
      */
     QgsPoint mLastMapPosition;