Add global option to disable default light (#1146)

* Headlight attached to camera can now be disabled.

* Default material properties that better support a variety of lights.

* Updated variable and method names. No functional changes.

* Removed material property changes added in caa01a5

* Minimise PR diff

src/rviz/visualization_manager.cpp

@@ -178,6 +178,10 @@ VisualizationManager::VisualizationManager( RenderPanel* render_panel, WindowMan
                                    "RViz will try to render this many frames per second.",
                                    global_options_, SLOT( updateFps() ), this );
 
+  default_light_enabled_property_ = new BoolProperty( "Default Light", true,
+                                                      "Light source attached to the current 3D view.",
+                                                      global_options_, SLOT( updateDefaultLightVisible() ), this );
+
   root_display_group_->initialize( this ); // only initialize() a Display after its sub-properties are created.
   root_display_group_->setEnabled( true );
 
@@ -518,6 +522,11 @@ void VisualizationManager::updateFps()
   }
 }
 
+void VisualizationManager::updateDefaultLightVisible()
+{
+  directional_light_->setVisible(default_light_enabled_property_->getBool());
+}
+
 void VisualizationManager::handleMouseEvent( const ViewportMouseEvent& vme )
 {
   //process pending mouse events

src/rviz/visualization_manager.h

@@ -69,6 +69,7 @@ class DisplayFactory;
 class DisplayGroup;
 class FrameManager;
 class Property;
+class BoolProperty;
 class IntProperty;
 class PropertyTreeModel;
 class RenderPanel;
@@ -368,6 +369,7 @@ protected Q_SLOTS:
   TfFrameProperty* fixed_frame_property_;          ///< Frame to transform fixed data to
   StatusList* global_status_;
   IntProperty* fps_property_;
+  BoolProperty* default_light_enabled_property_;
 
   RenderPanel* render_panel_;
 
@@ -396,6 +398,7 @@ private Q_SLOTS:
   void updateFixedFrame();
   void updateBackgroundColor();
   void updateFps();
+  void updateDefaultLightVisible();
 
 private:
   DisplayFactory* display_factory_;