From ca513efc1d2acd339580efbaa7c85dcac8e6a5fb Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Thu, 28 Feb 2008 20:02:43 +0000
Subject: [PATCH] Added LODScaleHandler

---
 applications/osgviewer/osgviewer.cpp  |  3 ++
 include/osgViewer/ViewerEventHandlers | 37 ++++++++++++++---
 src/osgViewer/ViewerEventHandlers.cpp | 59 +++++++++++++++++++++++++++
 3 files changed, 94 insertions(+), 5 deletions(-)

diff --git a/applications/osgviewer/osgviewer.cpp b/applications/osgviewer/osgviewer.cpp
index 7e99a2a49..e3730c600 100644
--- a/applications/osgviewer/osgviewer.cpp
+++ b/applications/osgviewer/osgviewer.cpp
@@ -118,6 +118,9 @@ int main(int argc, char** argv)
     // add the record camera path handler
     viewer.addEventHandler(new osgViewer::RecordCameraPathHandler);
 
+    // add the LOD Scale handler
+    viewer.addEventHandler(new osgViewer::LODScaleHandler);
+
     // load the data
     osg::ref_ptr<osg::Node> loadedModel = osgDB::readNodeFiles(arguments);
     if (!loadedModel) 
diff --git a/include/osgViewer/ViewerEventHandlers b/include/osgViewer/ViewerEventHandlers
index f8ebbd5cd..34c764809 100644
--- a/include/osgViewer/ViewerEventHandlers
+++ b/include/osgViewer/ViewerEventHandlers
@@ -216,11 +216,11 @@ protected:
 };
 
 /**
-Event handler allowing the user to record the animation "path" of a camera. In it's current
-implementation, this handler cannot guarantee the final view matrix is correct; it is
-conceivable that the matrix may be one frame off. Eh--not a big deal! :)
-TODO: Write the file as we go, not when it's all done.
-TODO: Create an osgviewer on-screen indication that animation is taking place.
+ * Event handler allowing the user to record the animation "path" of a camera. In it's current
+ * implementation, this handler cannot guarantee the final view matrix is correct; it is
+ * conceivable that the matrix may be one frame off. Eh--not a big deal! :)
+ * TODO: Write the file as we go, not when it's all done.
+ * TODO: Create an osgviewer on-screen indication that animation is taking place.
 */
 class OSGVIEWER_EXPORT RecordCameraPathHandler : public osgGA::GUIEventHandler
 {
@@ -257,6 +257,33 @@ protected:
         osg::ref_ptr<osgGA::MatrixManipulator>          _oldManipulator;
 };
 
+/** Event handler for increase/decreasing LODScale.*/
+class OSGVIEWER_EXPORT LODScaleHandler : public osgGA::GUIEventHandler 
+{
+    public: 
+
+        LODScaleHandler();
+
+        void setKeyEventIncreaseLODScale(int key) { _keyEventIncreaseLODScale = key; }
+        int getKeyEventIncreaseLODScale() const { return _keyEventIncreaseLODScale; }
+        
+        void setKeyEventDecreaseLODScale(int key) { _keyEventDecreaseLODScale = key; }
+        int getKeyEventDecreaseLODScale() const { return _keyEventDecreaseLODScale; }
+
+        bool handle(const osgGA::GUIEventAdapter& ea, osgGA::GUIActionAdapter& aa);
+
+        /** Get the keyboard and mouse usage of this manipulator.*/
+        virtual void getUsage(osg::ApplicationUsage& usage) const;
+
+    protected:
+
+
+        int _keyEventIncreaseLODScale;
+        int _keyEventDecreaseLODScale;
+        
+        
+};
+
 }
 
 #endif
diff --git a/src/osgViewer/ViewerEventHandlers.cpp b/src/osgViewer/ViewerEventHandlers.cpp
index a079f3888..148101613 100644
--- a/src/osgViewer/ViewerEventHandlers.cpp
+++ b/src/osgViewer/ViewerEventHandlers.cpp
@@ -15,6 +15,8 @@
 #include <float.h>
 
 #include <fstream>
+#include <sstream>
+
 #include <osgViewer/Viewer>
 #include <osgViewer/ViewerEventHandlers>
 
@@ -515,4 +517,61 @@ bool RecordCameraPathHandler::handle(const osgGA::GUIEventAdapter &ea, osgGA::GU
     return false;
 }
 
+LODScaleHandler::LODScaleHandler():
+    _keyEventIncreaseLODScale('*'),
+    _keyEventDecreaseLODScale('/')
+{
+}
+
+bool LODScaleHandler::handle(const osgGA::GUIEventAdapter& ea, osgGA::GUIActionAdapter& aa)
+{
+    osgViewer::View* view = dynamic_cast<osgViewer::View*>(&aa);
+    osg::Camera* camera = view ? view->getCamera() : 0;
+    if (!camera) return false;
+
+    if (ea.getHandled()) return false;
+
+    switch(ea.getEventType())
+    {
+        case(osgGA::GUIEventAdapter::KEYUP):
+        {
+            if (ea.getKey() == _keyEventIncreaseLODScale)
+            {
+                camera->setLODScale(camera->getLODScale()*1.1);
+                osg::notify(osg::NOTICE)<<"LODScale = "<<camera->getLODScale()<<std::endl;
+                return true;
+            }
+
+            else if (ea.getKey() == _keyEventDecreaseLODScale)
+            {
+                camera->setLODScale(camera->getLODScale()/1.1);
+                osg::notify(osg::NOTICE)<<"LODScale = "<<camera->getLODScale()<<std::endl;
+                return true;
+            }        
+
+            break;
+        }
+    default:
+        break;
+    }
+
+    return false;
+}
+
+void LODScaleHandler::getUsage(osg::ApplicationUsage& usage) const
+{
+    {
+        std::ostringstream ostr;
+        ostr<<char(_keyEventIncreaseLODScale);
+        usage.addKeyboardMouseBinding(ostr.str(),"Increase LODScale.");
+    }
+    
+    {
+        std::ostringstream ostr;
+        ostr<<char(_keyEventDecreaseLODScale);
+        usage.addKeyboardMouseBinding(ostr.str(),"Decrease LODScale.");
+    }
+}
+
+
 }