Terrain: use the main camera's viewpoint for intersection tests

Fixes lag spikes caused by intersection tests loading/unloading terrain pages.

apps/openmw/mwrender/renderingmanager.cpp

@@ -222,6 +222,7 @@ namespace MWRender
             mTerrain.reset(new Terrain::QuadTreeWorld(sceneRoot, mRootNode, mResourceSystem, mTerrainStorage, Mask_Terrain, Mask_PreCompile));
         else
             mTerrain.reset(new Terrain::TerrainGrid(sceneRoot, mRootNode, mResourceSystem, mTerrainStorage, Mask_Terrain, Mask_PreCompile));
+        mTerrain->setDefaultViewer(mViewer->getCamera());
 
         mCamera.reset(new Camera(mViewer->getCamera()));
 

components/terrain/quadtreenode.cpp

@@ -99,8 +99,10 @@ void QuadTreeNode::traverse(osg::NodeVisitor &nv)
     if (!hasValidBounds())
         return;
 
-    if ((mLodCallback && mLodCallback->isSufficientDetail(this, nv.getEyePoint())) || !getNumChildren())
-        getView(nv)->add(this, true);
+    ViewData* vd = getView(nv);
+
+    if ((mLodCallback && mLodCallback->isSufficientDetail(this, vd->getEyePoint())) || !getNumChildren())
+        vd->add(this, true);
     else
         osg::Group::traverse(nv);
 }
@@ -130,11 +132,20 @@ ViewData* QuadTreeNode::getView(osg::NodeVisitor &nv)
     if (nv.getVisitorType() == osg::NodeVisitor::CULL_VISITOR)
     {
         osgUtil::CullVisitor* cv = static_cast<osgUtil::CullVisitor*>(&nv);
-        return mViewDataMap->getViewData(cv->getCurrentCamera(), true);
+        ViewData* vd = mViewDataMap->getViewData(cv->getCurrentCamera(), true);
+        vd->setEyePoint(nv.getEyePoint());
+        return vd;
     }
     else // INTERSECTION_VISITOR
     {
-        return mViewDataMap->getViewData(&nv, (nv.referenceCount() > 0)); // if no referenceCount, the visitor was allocated on the stack
+        static osg::ref_ptr<osg::Object> dummyObj = new osg::DummyObject;
+        ViewData* vd = mViewDataMap->getViewData(dummyObj.get(), true);
+        ViewData* defaultView = mViewDataMap->getDefaultView();
+        if (defaultView->hasEyePoint())
+            vd->setEyePoint(defaultView->getEyePoint());
+        else
+            vd->setEyePoint(nv.getEyePoint());
+        return vd;
     }
 }
 

components/terrain/quadtreeworld.cpp

@@ -456,5 +456,10 @@ void QuadTreeWorld::reportStats(unsigned int frameNumber, osg::Stats *stats)
     stats->setAttribute(frameNumber, "Composite", mCompositeMapRenderer->getCompileSetSize());
 }
 
+void QuadTreeWorld::setDefaultViewer(osg::Object *obj)
+{
+    mViewDataMap->setDefaultViewer(obj);
+}
+
 
 }

components/terrain/quadtreeworld.hpp

@@ -33,6 +33,8 @@ namespace Terrain
 
         void reportStats(unsigned int frameNumber, osg::Stats* stats);
 
+        virtual void setDefaultViewer(osg::Object* obj);
+
     private:
         void ensureQuadTreeBuilt();
 

components/terrain/viewdata.cpp

@@ -7,6 +7,7 @@ ViewData::ViewData()
     : mNumEntries(0)
     , mFrameLastUsed(0)
     , mChanged(false)
+    , mHasEyePoint(false)
 {
 
 }
@@ -43,6 +44,22 @@ bool ViewData::hasChanged() const
     return mChanged;
 }
 
+bool ViewData::hasEyePoint() const
+{
+    return mHasEyePoint;
+}
+
+void ViewData::setEyePoint(const osg::Vec3f &eye)
+{
+    mEyePoint = eye;
+    mHasEyePoint = true;
+}
+
+const osg::Vec3f& ViewData::getEyePoint() const
+{
+    return mEyePoint;
+}
+
 void ViewData::reset(unsigned int frame)
 {
     // clear any unused entries
@@ -150,5 +167,15 @@ void ViewDataMap::clear()
     mViewVector.clear();
 }
 
+void ViewDataMap::setDefaultViewer(osg::Object *viewer)
+{
+    mDefaultViewer = viewer;
+}
+
+ViewData* ViewDataMap::getDefaultView()
+{
+    return getViewData(mDefaultViewer, true);
+}
+
 
 }

components/terrain/viewdata.hpp

@@ -52,12 +52,19 @@ namespace Terrain
         /// @return Have any nodes changed since the last frame
         bool hasChanged() const;
 
+        bool hasEyePoint() const;
+
+        void setEyePoint(const osg::Vec3f& eye);
+        const osg::Vec3f& getEyePoint() const;
+
     private:
         std::vector<Entry> mEntries;
         unsigned int mNumEntries;
         unsigned int mFrameLastUsed;
         bool mChanged;
         osg::ref_ptr<osg::Object> mViewer;
+        osg::Vec3f mEyePoint;
+        bool mHasEyePoint;
     };
 
     class ViewDataMap : public osg::Referenced
@@ -71,6 +78,10 @@ namespace Terrain
 
         void clear();
 
+        void setDefaultViewer(osg::Object* viewer);
+
+        ViewData* getDefaultView();
+
     private:
         std::list<ViewData> mViewVector;
 
@@ -78,6 +89,8 @@ namespace Terrain
         Map mViews;
 
         std::deque<ViewData*> mUnusedViews;
+
+        osg::ref_ptr<osg::Object> mDefaultViewer;
     };
 
 }

components/terrain/world.hpp

@@ -14,6 +14,7 @@ namespace osg
     class Group;
     class Stats;
     class Node;
+    class Object;
 }
 
 namespace Resource
@@ -87,6 +88,9 @@ namespace Terrain
 
         virtual void reportStats(unsigned int frameNumber, osg::Stats* stats) {}
 
+        /// Set the default viewer (usually a Camera), used as viewpoint for any viewers that don't use their own viewpoint.
+        virtual void setDefaultViewer(osg::Object* obj) {}
+
         Storage* getStorage() { return mStorage; }
 
     protected: