# HG changeset patch
# User Chris Cannam
# Date 1161251847 0
# Node ID 9c40dc10c88cd683d6b997621d9e8b42b64f079b
# Parent  d0b95a8cac96cfcc6ab708e7efce18315461b341
* Rename the existing Panner to Overview (big duh!)
* Fixes to the new Panner.

diff -r d0b95a8cac96 -r 9c40dc10c88c view/Overview.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/view/Overview.cpp	Thu Oct 19 09:57:27 2006 +0000
@@ -0,0 +1,213 @@
+/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
+
+/*
+    Sonic Visualiser
+    An audio file viewer and annotation editor.
+    Centre for Digital Music, Queen Mary, University of London.
+    This file copyright 2006 Chris Cannam.
+    
+    This program is free software; you can redistribute it and/or
+    modify it under the terms of the GNU General Public License as
+    published by the Free Software Foundation; either version 2 of the
+    License, or (at your option) any later version.  See the file
+    COPYING included with this distribution for more information.
+*/
+
+#include "Overview.h"
+#include "layer/Layer.h"
+#include "data/model/Model.h"
+#include "base/ZoomConstraint.h"
+
+#include <QPaintEvent>
+#include <QPainter>
+#include <iostream>
+
+using std::cerr;
+using std::endl;
+
+Overview::Overview(QWidget *w) :
+    View(w, false),
+    m_clickedInRange(false)
+{
+    setObjectName(tr("Overview"));
+    m_followPan = false;
+    m_followZoom = false;
+}
+
+void
+Overview::modelChanged(size_t startFrame, size_t endFrame)
+{
+    View::modelChanged(startFrame, endFrame);
+}
+
+void
+Overview::modelReplaced()
+{
+    View::modelReplaced();
+}
+
+void
+Overview::registerView(View *widget)
+{
+    m_widgets.insert(widget);
+    update(); 
+}
+
+void
+Overview::unregisterView(View *widget)
+{
+    m_widgets.erase(widget);
+    update();
+}
+
+void
+Overview::viewManagerCentreFrameChanged(void *p, unsigned long f, bool)
+{
+//    std::cerr << "Overview[" << this << "]::viewManagerCentreFrameChanged(" 
+//	      << p << ", " << f << ")" << std::endl;
+
+    if (p == this) return;
+    if (m_widgets.find(p) != m_widgets.end()) {
+	update();
+    }
+}
+
+void
+Overview::viewManagerZoomLevelChanged(void *p, unsigned long z, bool)
+{
+    if (p == this) return;
+    if (m_widgets.find(p) != m_widgets.end()) {
+	update();
+    }
+}
+
+void
+Overview::viewManagerPlaybackFrameChanged(unsigned long f)
+{
+    bool changed = false;
+
+    if (getXForFrame(m_playPointerFrame) != getXForFrame(f)) changed = true;
+    m_playPointerFrame = f;
+
+    if (changed) update();
+}
+
+void
+Overview::paintEvent(QPaintEvent *e)
+{
+    // Recalculate zoom in case the size of the widget has changed.
+
+    size_t startFrame = getModelsStartFrame();
+    size_t frameCount = getModelsEndFrame() - getModelsStartFrame();
+    int zoomLevel = frameCount / width();
+    if (zoomLevel < 1) zoomLevel = 1;
+    zoomLevel = getZoomConstraintBlockSize(zoomLevel,
+					   ZoomConstraint::RoundUp);
+    if (zoomLevel != m_zoomLevel) {
+	m_zoomLevel = zoomLevel;
+	emit zoomLevelChanged(this, m_zoomLevel, m_followZoom);
+    }
+    size_t centreFrame = startFrame + m_zoomLevel * (width() / 2);
+    if (centreFrame > (startFrame + getModelsEndFrame())/2) {
+	centreFrame = (startFrame + getModelsEndFrame())/2;
+    }
+    if (centreFrame != m_centreFrame) {
+	m_centreFrame = centreFrame;
+	emit centreFrameChanged(this, m_centreFrame, false);
+    }
+
+    View::paintEvent(e);
+
+    QPainter paint;
+    paint.begin(this);
+
+    QRect r(rect());
+
+    if (e) {
+	r = e->rect();
+	paint.setClipRect(r);
+    }
+
+    paint.setPen(Qt::black);
+
+    int y = 0;
+
+    int prevx0 = -10;
+    int prevx1 = -10;
+
+    for (WidgetSet::iterator i = m_widgets.begin(); i != m_widgets.end(); ++i) {
+	if (!*i) continue;
+
+	View *w = (View *)*i;
+
+	long f0 = w->getFrameForX(0);
+	long f1 = w->getFrameForX(w->width());
+
+	int x0 = getXForFrame(f0);
+	int x1 = getXForFrame(f1);
+
+	if (x0 != prevx0 || x1 != prevx1) {
+	    y += height() / 10 + 1;
+	    prevx0 = x0;
+	    prevx1 = x1;
+	}
+
+	if (x1 <= x0) x1 = x0 + 1;
+	
+	paint.drawRect(x0, y, x1 - x0, height() - 2 * y);
+    }
+
+    paint.end();
+}
+
+void
+Overview::mousePressEvent(QMouseEvent *e)
+{
+    m_clickPos = e->pos();
+    for (WidgetSet::iterator i = m_widgets.begin(); i != m_widgets.end(); ++i) {
+	if (*i) {
+	    m_clickedInRange = true;
+	    m_dragCentreFrame = ((View *)*i)->getCentreFrame();
+	    break;
+	}
+    }
+}
+
+void
+Overview::mouseReleaseEvent(QMouseEvent *e)
+{
+    if (m_clickedInRange) {
+	mouseMoveEvent(e);
+    }
+    m_clickedInRange = false;
+}
+
+void
+Overview::mouseMoveEvent(QMouseEvent *e)
+{
+    if (!m_clickedInRange) return;
+
+    long xoff = int(e->x()) - int(m_clickPos.x());
+    long frameOff = xoff * m_zoomLevel;
+    
+    size_t newCentreFrame = m_dragCentreFrame;
+    if (frameOff > 0) {
+	newCentreFrame += frameOff;
+    } else if (newCentreFrame >= size_t(-frameOff)) {
+	newCentreFrame += frameOff;
+    } else {
+	newCentreFrame = 0;
+    }
+
+    if (newCentreFrame >= getModelsEndFrame()) {
+	newCentreFrame = getModelsEndFrame();
+	if (newCentreFrame > 0) --newCentreFrame;
+    }
+    
+    if (std::max(m_centreFrame, newCentreFrame) -
+	std::min(m_centreFrame, newCentreFrame) > size_t(m_zoomLevel)) {
+	emit centreFrameChanged(this, newCentreFrame, true);
+    }
+}
+
+
diff -r d0b95a8cac96 -r 9c40dc10c88c view/Overview.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/view/Overview.h	Thu Oct 19 09:57:27 2006 +0000
@@ -0,0 +1,67 @@
+/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
+
+/*
+    Sonic Visualiser
+    An audio file viewer and annotation editor.
+    Centre for Digital Music, Queen Mary, University of London.
+    This file copyright 2006 Chris Cannam.
+    
+    This program is free software; you can redistribute it and/or
+    modify it under the terms of the GNU General Public License as
+    published by the Free Software Foundation; either version 2 of the
+    License, or (at your option) any later version.  See the file
+    COPYING included with this distribution for more information.
+*/
+
+#ifndef _OVERVIEW_H_
+#define _OVERVIEW_H_
+
+#include "View.h"
+
+#include <QPoint>
+
+class QWidget;
+class QPaintEvent;
+class Layer;
+class View;
+
+#include <map>
+
+class Overview : public View
+{
+    Q_OBJECT
+
+public:
+    Overview(QWidget *parent = 0);
+
+    void registerView(View *widget);
+    void unregisterView(View *widget);
+
+    virtual QString getPropertyContainerIconName() const { return "panner"; }
+
+public slots:
+    virtual void modelChanged(size_t startFrame, size_t endFrame);
+    virtual void modelReplaced();
+
+    virtual void viewManagerCentreFrameChanged(void *, unsigned long, bool);
+    virtual void viewManagerZoomLevelChanged(void *, unsigned long, bool);
+    virtual void viewManagerPlaybackFrameChanged(unsigned long);
+
+protected:
+    virtual void paintEvent(QPaintEvent *e);
+    virtual void mousePressEvent(QMouseEvent *e);
+    virtual void mouseReleaseEvent(QMouseEvent *e);
+    virtual void mouseMoveEvent(QMouseEvent *e);
+    virtual bool shouldLabelSelections() const { return false; }
+
+    QPoint m_clickPos;
+    QPoint m_mousePos;
+    bool m_clickedInRange;
+    size_t m_dragCentreFrame;
+    
+    typedef std::set<void *> WidgetSet;
+    WidgetSet m_widgets;
+};
+
+#endif
+
diff -r d0b95a8cac96 -r 9c40dc10c88c view/Pane.cpp
--- a/view/Pane.cpp	Wed Oct 18 16:38:30 2006 +0000
+++ b/view/Pane.cpp	Thu Oct 19 09:57:27 2006 +0000
@@ -85,7 +85,7 @@
         m_headsUpDisplay->setLayout(layout);
         
         m_hthumb = new Thumbwheel(Qt::Horizontal);
-        layout->addWidget(m_hthumb, 1, 0, 2, 1);
+        layout->addWidget(m_hthumb, 1, 0, 1, 2);
         m_hthumb->setFixedWidth(70);
         m_hthumb->setFixedHeight(16);
         m_hthumb->setDefaultValue(0);
@@ -95,8 +95,9 @@
 
         m_vpan = new Panner;
         layout->addWidget(m_vpan, 0, 1);
-        m_vpan->setFixedWidth(16);
+        m_vpan->setFixedWidth(12);
         m_vpan->setFixedHeight(70);
+//        m_vpan->setRectExtents(0.1, 0.1, 0.4, 0.4);
 
         m_vthumb = new Thumbwheel(Qt::Vertical);
         layout->addWidget(m_vthumb, 0, 2);
@@ -559,7 +560,7 @@
 
         if (m_manager->getZoomWheelsEnabled()) {
             lly -= 20;
-            llx -= 20;
+            llx -= 36;
         }
 
 	if (r.x() + r.width() >= llx) {
diff -r d0b95a8cac96 -r 9c40dc10c88c view/Panner.cpp
--- a/view/Panner.cpp	Wed Oct 18 16:38:30 2006 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,216 +0,0 @@
-/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
-
-/*
-    Sonic Visualiser
-    An audio file viewer and annotation editor.
-    Centre for Digital Music, Queen Mary, University of London.
-    This file copyright 2006 Chris Cannam.
-    
-    This program is free software; you can redistribute it and/or
-    modify it under the terms of the GNU General Public License as
-    published by the Free Software Foundation; either version 2 of the
-    License, or (at your option) any later version.  See the file
-    COPYING included with this distribution for more information.
-*/
-
-#include "Panner.h"
-#include "layer/Layer.h"
-#include "data/model/Model.h"
-#include "base/ZoomConstraint.h"
-
-#include <QPaintEvent>
-#include <QPainter>
-#include <iostream>
-
-using std::cerr;
-using std::endl;
-
-Panner::Panner(QWidget *w) :
-    View(w, false),
-    m_clickedInRange(false)
-{
-    setObjectName(tr("Panner"));
-    m_followPan = false;
-    m_followZoom = false;
-}
-
-void
-Panner::modelChanged(size_t startFrame, size_t endFrame)
-{
-    View::modelChanged(startFrame, endFrame);
-}
-
-void
-Panner::modelReplaced()
-{
-    View::modelReplaced();
-}
-
-void
-Panner::registerView(View *widget)
-{
-    m_widgets.insert(widget);
-    update(); 
-}
-
-void
-Panner::unregisterView(View *widget)
-{
-    m_widgets.erase(widget);
-    update();
-}
-
-void
-Panner::viewManagerCentreFrameChanged(void *p, unsigned long f, bool)
-{
-//    std::cerr << "Panner[" << this << "]::viewManagerCentreFrameChanged(" 
-//	      << p << ", " << f << ")" << std::endl;
-
-    if (p == this) return;
-    if (m_widgets.find(p) != m_widgets.end()) {
-	update();
-    }
-}
-
-void
-Panner::viewManagerZoomLevelChanged(void *p, unsigned long z, bool)
-{
-    if (p == this) return;
-    if (m_widgets.find(p) != m_widgets.end()) {
-	update();
-    }
-}
-
-void
-Panner::viewManagerPlaybackFrameChanged(unsigned long f)
-{
-    bool changed = false;
-
-    if (getXForFrame(m_playPointerFrame) != getXForFrame(f)) changed = true;
-    m_playPointerFrame = f;
-
-    if (changed) update();
-}
-
-void
-Panner::paintEvent(QPaintEvent *e)
-{
-    // Recalculate zoom in case the size of the widget has changed.
-
-    size_t startFrame = getModelsStartFrame();
-    size_t frameCount = getModelsEndFrame() - getModelsStartFrame();
-    int zoomLevel = frameCount / width();
-    if (zoomLevel < 1) zoomLevel = 1;
-    zoomLevel = getZoomConstraintBlockSize(zoomLevel,
-					   ZoomConstraint::RoundUp);
-    if (zoomLevel != m_zoomLevel) {
-	m_zoomLevel = zoomLevel;
-	emit zoomLevelChanged(this, m_zoomLevel, m_followZoom);
-    }
-    size_t centreFrame = startFrame + m_zoomLevel * (width() / 2);
-    if (centreFrame > (startFrame + getModelsEndFrame())/2) {
-	centreFrame = (startFrame + getModelsEndFrame())/2;
-    }
-    if (centreFrame != m_centreFrame) {
-	m_centreFrame = centreFrame;
-	emit centreFrameChanged(this, m_centreFrame, false);
-    }
-
-    View::paintEvent(e);
-
-    QPainter paint;
-    paint.begin(this);
-
-    QRect r(rect());
-
-    if (e) {
-	r = e->rect();
-	paint.setClipRect(r);
-    }
-
-    paint.setPen(Qt::black);
-
-    int y = 0;
-
-    int prevx0 = -10;
-    int prevx1 = -10;
-
-    for (WidgetSet::iterator i = m_widgets.begin(); i != m_widgets.end(); ++i) {
-	if (!*i) continue;
-
-	View *w = (View *)*i;
-
-	long f0 = w->getFrameForX(0);
-	long f1 = w->getFrameForX(w->width());
-
-	int x0 = getXForFrame(f0);
-	int x1 = getXForFrame(f1);
-
-	if (x0 != prevx0 || x1 != prevx1) {
-	    y += height() / 10 + 1;
-	    prevx0 = x0;
-	    prevx1 = x1;
-	}
-
-	if (x1 <= x0) x1 = x0 + 1;
-	
-	paint.drawRect(x0, y, x1 - x0, height() - 2 * y);
-    }
-
-    paint.end();
-}
-
-void
-Panner::mousePressEvent(QMouseEvent *e)
-{
-    m_clickPos = e->pos();
-    for (WidgetSet::iterator i = m_widgets.begin(); i != m_widgets.end(); ++i) {
-	if (*i) {
-	    m_clickedInRange = true;
-	    m_dragCentreFrame = ((View *)*i)->getCentreFrame();
-	    break;
-	}
-    }
-}
-
-void
-Panner::mouseReleaseEvent(QMouseEvent *e)
-{
-    if (m_clickedInRange) {
-	mouseMoveEvent(e);
-    }
-    m_clickedInRange = false;
-}
-
-void
-Panner::mouseMoveEvent(QMouseEvent *e)
-{
-    if (!m_clickedInRange) return;
-
-    long xoff = int(e->x()) - int(m_clickPos.x());
-    long frameOff = xoff * m_zoomLevel;
-    
-    size_t newCentreFrame = m_dragCentreFrame;
-    if (frameOff > 0) {
-	newCentreFrame += frameOff;
-    } else if (newCentreFrame >= size_t(-frameOff)) {
-	newCentreFrame += frameOff;
-    } else {
-	newCentreFrame = 0;
-    }
-
-    if (newCentreFrame >= getModelsEndFrame()) {
-	newCentreFrame = getModelsEndFrame();
-	if (newCentreFrame > 0) --newCentreFrame;
-    }
-    
-    if (std::max(m_centreFrame, newCentreFrame) -
-	std::min(m_centreFrame, newCentreFrame) > size_t(m_zoomLevel)) {
-	emit centreFrameChanged(this, newCentreFrame, true);
-    }
-}
-
-#ifdef INCLUDE_MOCFILES
-#include "Panner.moc.cpp"
-#endif
-
diff -r d0b95a8cac96 -r 9c40dc10c88c view/Panner.h
--- a/view/Panner.h	Wed Oct 18 16:38:30 2006 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,67 +0,0 @@
-/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
-
-/*
-    Sonic Visualiser
-    An audio file viewer and annotation editor.
-    Centre for Digital Music, Queen Mary, University of London.
-    This file copyright 2006 Chris Cannam.
-    
-    This program is free software; you can redistribute it and/or
-    modify it under the terms of the GNU General Public License as
-    published by the Free Software Foundation; either version 2 of the
-    License, or (at your option) any later version.  See the file
-    COPYING included with this distribution for more information.
-*/
-
-#ifndef _PAN_WIDGET_H_
-#define _PAN_WIDGET_H_
-
-#include "View.h"
-
-#include <QPoint>
-
-class QWidget;
-class QPaintEvent;
-class Layer;
-class View;
-
-#include <map>
-
-class Panner : public View
-{
-    Q_OBJECT
-
-public:
-    Panner(QWidget *parent = 0);
-
-    void registerView(View *widget);
-    void unregisterView(View *widget);
-
-    virtual QString getPropertyContainerIconName() const { return "panner"; }
-
-public slots:
-    virtual void modelChanged(size_t startFrame, size_t endFrame);
-    virtual void modelReplaced();
-
-    virtual void viewManagerCentreFrameChanged(void *, unsigned long, bool);
-    virtual void viewManagerZoomLevelChanged(void *, unsigned long, bool);
-    virtual void viewManagerPlaybackFrameChanged(unsigned long);
-
-protected:
-    virtual void paintEvent(QPaintEvent *e);
-    virtual void mousePressEvent(QMouseEvent *e);
-    virtual void mouseReleaseEvent(QMouseEvent *e);
-    virtual void mouseMoveEvent(QMouseEvent *e);
-    virtual bool shouldLabelSelections() const { return false; }
-
-    QPoint m_clickPos;
-    QPoint m_mousePos;
-    bool m_clickedInRange;
-    size_t m_dragCentreFrame;
-    
-    typedef std::set<void *> WidgetSet;
-    WidgetSet m_widgets;
-};
-
-#endif
-
diff -r d0b95a8cac96 -r 9c40dc10c88c view/view.pro
--- a/view/view.pro	Wed Oct 18 16:38:30 2006 +0000
+++ b/view/view.pro	Thu Oct 19 09:57:27 2006 +0000
@@ -14,5 +14,13 @@
 MOC_DIR = tmp_moc
 
 # Input
-HEADERS += Pane.h PaneStack.h Panner.h View.h ViewManager.h
-SOURCES += Pane.cpp PaneStack.cpp Panner.cpp View.cpp ViewManager.cpp
+HEADERS += Overview.h \
+           Pane.h \
+           PaneStack.h \
+           View.h \
+           ViewManager.h
+SOURCES += Overview.cpp \
+           Pane.cpp \
+           PaneStack.cpp \
+           View.cpp \
+           ViewManager.cpp
diff -r d0b95a8cac96 -r 9c40dc10c88c widgets/Panner.cpp
--- a/widgets/Panner.cpp	Wed Oct 18 16:38:30 2006 +0000
+++ b/widgets/Panner.cpp	Thu Oct 19 09:57:27 2006 +0000
@@ -27,7 +27,11 @@
     m_rectX(0),
     m_rectY(0),
     m_rectWidth(1),
-    m_rectHeight(1)
+    m_rectHeight(1),
+    m_defaultCentreX(0),
+    m_defaultCentreY(0),
+    m_defaultsSet(false),
+    m_clicked(false)
 {
 }
 
@@ -38,38 +42,81 @@
 void
 Panner::mousePressEvent(QMouseEvent *e)
 {
+    if (e->button() == Qt::LeftButton) {
+        m_clicked = true;
+        m_clickPos = e->pos();
+        m_dragStartX = m_rectX;
+        m_dragStartY = m_rectY;
+    } else if (e->button() == Qt::MidButton) {
+        resetToDefault();
+    }
 }
 
 void
 Panner::mouseDoubleClickEvent(QMouseEvent *e)
 {
+    resetToDefault();
 }
 
 void
 Panner::mouseMoveEvent(QMouseEvent *e)
 {
+    if (!m_clicked) return;
+
+    float dx = float(e->pos().x() - m_clickPos.x()) / float(width());
+    float dy = float(e->pos().y() - m_clickPos.y()) / float(height());
+    
+    m_rectX = m_dragStartX + dx;
+    m_rectY = m_dragStartY + dy;
+    
+    normalise();
+    emitAndUpdate();
 }
 
 void
 Panner::mouseReleaseEvent(QMouseEvent *e)
 {
+    if (!m_clicked) return;
+
+    mouseMoveEvent(e);
+    m_clicked = false;
 }
 
 void
 Panner::wheelEvent(QWheelEvent *e)
 {
+    if (e->delta() > 0) {
+        m_rectY += 0.1;
+    } else {
+        m_rectY -= 0.1;
+    }
+
+    normalise();
+    emitAndUpdate();
 }
 
 void
 Panner::paintEvent(QPaintEvent *e)
 {
     QPainter paint(this);
-    paint.fillRect(rect(), palette().background().color());
     paint.setRenderHint(QPainter::Antialiasing, false);
+
+    QColor bg(palette().background().color());
+    bg.setAlpha(80);
+
     paint.setPen(palette().dark().color());
-    paint.setBrush(palette().highlight().color());
-    paint.drawRect(QRectF(width() * m_rectX, height() - height() * m_rectY,
-                          width() * m_rectWidth, height() * m_rectHeight));
+    paint.setBrush(bg);
+    paint.drawRect(0, 0, width(), height());
+
+    QColor hl(palette().highlight().color());
+    hl.setAlpha(80);
+
+    paint.setBrush(hl);
+
+    paint.drawRect(lrintf(width() * m_rectX),
+                   lrintf(height() * m_rectY),
+                   lrintf(width() * m_rectWidth),
+                   lrintf(height() * m_rectHeight));
 }
 
 void
@@ -81,13 +128,19 @@
     if (m_rectX < 0) m_rectX = 0;
     if (m_rectY + m_rectHeight > 1.0) m_rectY = 1.0 - m_rectHeight;
     if (m_rectY < 0) m_rectY = 0;
+
+    if (!m_defaultsSet) {
+        m_defaultCentreX = centreX();
+        m_defaultCentreY = centreY();
+        m_defaultsSet = true;
+    }
 }
 
 void
 Panner::emitAndUpdate()
 {
     emit rectExtentsChanged(m_rectX, m_rectY, m_rectWidth, m_rectHeight);
-    emit rectCentreMoved(m_rectX + (m_rectWidth/2), m_rectY + (m_rectHeight/2));
+    emit rectCentreMoved(centreX(), centreY());
     update();
 }  
 
@@ -100,10 +153,12 @@
         m_rectHeight == height) {
         return;
     }
+
     m_rectX = x0;
     m_rectY = y0;
     m_rectWidth = width;
     m_rectHeight = height;
+
     normalise();
     emitAndUpdate();
 }
@@ -139,7 +194,7 @@
 void
 Panner::setRectCentreY(float y)
 {
-    float y0 = y - m_rectWidth/2;
+    float y0 = y - m_rectHeight/2;
     if (y0 == m_rectY) return;
     m_rectY = y0;
     normalise();
@@ -152,5 +207,24 @@
     return QSize(30, 30);
 }
 
+void
+Panner::setDefaultRectCentre(float cx, float cy)
+{
+    m_defaultCentreX = cx;
+    m_defaultCentreY = cy;
+    m_defaultsSet = true;
+}
 
+void
+Panner::resetToDefault()
+{
+    float x0 = m_defaultCentreX - m_rectWidth/2;
+    float y0 = m_defaultCentreY - m_rectHeight/2;
+    if (x0 == m_rectX && y0 == m_rectY) return;
+    m_rectX = x0;
+    m_rectY = y0;
+    normalise();
+    emitAndUpdate();
+}
 
+
diff -r d0b95a8cac96 -r 9c40dc10c88c widgets/Panner.h
--- a/widgets/Panner.h	Wed Oct 18 16:38:30 2006 +0000
+++ b/widgets/Panner.h	Thu Oct 19 09:57:27 2006 +0000
@@ -26,6 +26,8 @@
     Panner(QWidget *parent = 0);
     virtual ~Panner();
 
+    void setDefaultRectCentre(float, float);
+
     virtual void mousePressEvent(QMouseEvent *e);
     virtual void mouseDoubleClickEvent(QMouseEvent *e);
     virtual void mouseMoveEvent(QMouseEvent *e);
@@ -89,11 +91,24 @@
 protected:
     void normalise();
     void emitAndUpdate();
+    void resetToDefault();
 
     float m_rectX;
     float m_rectY;
     float m_rectWidth;
     float m_rectHeight;
+
+    float m_defaultCentreX;
+    float m_defaultCentreY;
+    bool m_defaultsSet;
+
+    float centreX() const { return m_rectX + m_rectWidth/2; }
+    float centreY() const { return m_rectY + m_rectHeight/2; }
+
+    bool m_clicked;
+    QPoint m_clickPos;
+    float m_dragStartX;
+    float m_dragStartY;
 };
 
 #endif