From 8097d20c2addba06a748f838ac6b7d7cdb29df14 Mon Sep 17 00:00:00 2001
From: James Hogan <james@albanarts.com>
Date: Sat, 22 Nov 2008 11:39:57 +0000
Subject: [PATCH] Inverted mouse control and allowed range selecting without
 losing previous selection until unpress

---
 tcViewportWidget.cpp | 34 +++++++++++++++++++++++-----------
 tcViewportWidget.h   |  3 +++
 2 files changed, 26 insertions(+), 11 deletions(-)

diff --git a/tcViewportWidget.cpp b/tcViewportWidget.cpp
index 98d0ddd..25ad832 100644
--- a/tcViewportWidget.cpp
+++ b/tcViewportWidget.cpp
@@ -314,21 +314,33 @@ void tcViewportWidget::paintGL()
   glLineWidth(1);
 
   // Draw a fence around the selected region
-  if (m_mouseSlicing || m_sliced)
+  for (int i = 0; i < 2; ++i)
   {
-    tcGeo ending = (m_mouseSlicing ? m_mouseCoord : m_slice[1]);
+    tcGeo coord;
+    tcGeo ending;
     float colour[4] = {1.0f, 0.5f, 1.0f, 1.0f};
-    if (!m_mouseSlicing)
+    if (0 == i && m_mouseSlicing && m_mouseIntersecting)
     {
+      coord = m_mouseCoord;
+      ending = m_mouseStartCoord;
+    }
+    else if (1 == i && m_sliced)
+    {
+      coord = m_slice[0];
+      ending = m_slice[1];
       colour[0] = 0.0f;
       colour[3] = 0.5f;
     }
-    tcGeo delta = ending - m_slice[0];
+    else
+    {
+      continue;
+    }
+
+    tcGeo delta = ending - coord;
     int nlon = 2 + fabs(delta.lon())*10*meanRadius / m_observer->range();
     int nlat = 2 + fabs(delta.lat())*10*meanRadius / m_observer->range();
     double dlon = delta.lon() / nlon;
     double dlat = delta.lat() / nlat;
-    tcGeo coord = m_slice[0];
 
     glDisable(GL_CULL_FACE);
     glBegin(GL_TRIANGLE_STRIP);
@@ -416,12 +428,11 @@ void tcViewportWidget::mousePressEvent(QMouseEvent* event)
   else if (event->button() == Qt::RightButton)
   {
     bool ok;
-    m_slice[0] = geoAt(event->posF().x(), event->posF().y(), &ok);
+    m_mouseStartCoord = geoAt(event->posF().x(), event->posF().y(), &ok);
     m_mouseIntersecting = false;
     if (ok)
     {
       m_mouseSlicing = true;
-      m_sliced = false;
     }
   }
 }
@@ -435,9 +446,10 @@ void tcViewportWidget::mouseReleaseEvent(QMouseEvent* event)
   else if (m_mouseSlicing)
   {
     m_mouseSlicing = false;
+    m_sliced = m_mouseIntersecting;
     if (m_mouseIntersecting)
     {
-      m_sliced = true;
+      m_slice[0] = m_mouseStartCoord;
       m_slice[1] = m_mouseCoord;
     }
     updateGL();
@@ -452,16 +464,16 @@ void tcViewportWidget::wheelEvent(QWheelEvent* event)
   {
     if (event->modifiers().testFlag(Qt::ControlModifier))
     {
-      m_observer->adjustElevation(-delta);
+      m_observer->adjustElevation(delta);
     }
     else
     {
-      m_observer->adjustRange(delta);
+      m_observer->adjustRange(-delta);
     }
   }
   else
   {
-    m_observer->adjustAzimuth(delta);
+    m_observer->adjustAzimuth(-delta);
   }
   m_observer->setFocusAltitude(m_globe->radiusAt(m_observer->focus()));
 
diff --git a/tcViewportWidget.h b/tcViewportWidget.h
index 223877b..f766a7e 100644
--- a/tcViewportWidget.h
+++ b/tcViewportWidget.h
@@ -164,6 +164,9 @@ class tcViewportWidget : public QGLWidget
     /// Slicing with the mouse?
     bool m_mouseSlicing;
 
+    /// Start of mouse slicing action.
+    tcGeo m_mouseStartCoord;
+
     /// Sliced?
     bool m_sliced;
 
-- 
2.11.4.GIT