From a61c0aaee1a1473cc45951fb91deb26a42bd91d1 Mon Sep 17 00:00:00 2001
From: bzzt <bzzt@bzzt.bzzt>
Date: Wed, 20 Feb 2019 13:37:00 +0000
Subject: [PATCH] Do not load height data to the qued tree since we do not need
 it now

---
 components/terrain/quadtreenode.cpp  |  9 +++------
 components/terrain/quadtreenode.hpp  |  4 ++--
 components/terrain/quadtreeworld.cpp | 25 ++++++++++++-------------
 3 files changed, 17 insertions(+), 21 deletions(-)

diff --git a/components/terrain/quadtreenode.cpp b/components/terrain/quadtreenode.cpp
index 10f46c0eb..b92c37313 100644
--- a/components/terrain/quadtreenode.cpp
+++ b/components/terrain/quadtreenode.cpp
@@ -108,14 +108,11 @@ void QuadTreeNode::initNeighbours()
         getChild(i)->initNeighbours();
 }
 
-void QuadTreeNode::traverse(ViewData* vd, osg::NodeVisitor* nv, const osg::Vec3f& viewPoint, bool visible, float maxDist)
+void QuadTreeNode::traverse(ViewData* vd, const osg::Vec3f& viewPoint, float maxDist)
 {
     if (!hasValidBounds())
         return;
 
-    if (nv && nv->getVisitorType() == osg::NodeVisitor::CULL_VISITOR)
-        visible = visible && !static_cast<osgUtil::CullVisitor*>(nv)->isCulled(mBoundingBox);
-
     float dist = distance(viewPoint);
     if (dist > maxDist)
         return;
@@ -123,11 +120,11 @@ void QuadTreeNode::traverse(ViewData* vd, osg::NodeVisitor* nv, const osg::Vec3f
     bool stopTraversal = (mLodCallback->isSufficientDetail(this, dist)) || !getNumChildren();
 
     if (stopTraversal)
-        vd->add(this, visible);
+        vd->add(this, true);
     else
     {
         for (unsigned int i=0; i<getNumChildren(); ++i)
-            getChild(i)->traverse(vd, nv, viewPoint, visible, maxDist);
+            getChild(i)->traverse(vd, viewPoint, maxDist);
     }
 }
 
diff --git a/components/terrain/quadtreenode.hpp b/components/terrain/quadtreenode.hpp
index 96b08842f..391c2b75f 100644
--- a/components/terrain/quadtreenode.hpp
+++ b/components/terrain/quadtreenode.hpp
@@ -92,8 +92,8 @@ namespace Terrain
         const osg::Vec2f& getCenter() const;
 
         /// Optimized version of traverse() that doesn't incur the overhead of NodeVisitor double-dispatch or fetching the various variables.
-        /// Note this doesn't do any culling for non-cull visitors (e.g. intersections) so it shouldn't be used for those.
-        void traverse(ViewData* vd, osg::NodeVisitor* nv, const osg::Vec3f& viewPoint, bool visible, float maxDist);
+        /// Note this doesn't do any culling.
+        void traverse(ViewData* vd, const osg::Vec3f& viewPoint, float maxDist);
 
         /// Traverse to a specific node and add only that node.
         void traverseTo(ViewData* vd, float size, const osg::Vec2f& center);
diff --git a/components/terrain/quadtreeworld.cpp b/components/terrain/quadtreeworld.cpp
index 6fc41b04a..bd81c8637 100644
--- a/components/terrain/quadtreeworld.cpp
+++ b/components/terrain/quadtreeworld.cpp
@@ -188,15 +188,14 @@ public:
 
         if (node->getSize() <= mMinSize)
         {
-            // We arrived at a leaf
-            float minZ,maxZ;
-            if (mStorage->getMinMaxHeights(size, center, minZ, maxZ))
-            {
-                float cellWorldSize = mStorage->getCellWorldSize();
-                osg::BoundingBox boundingBox(osg::Vec3f((center.x()-halfSize)*cellWorldSize, (center.y()-halfSize)*cellWorldSize, minZ),
-                                        osg::Vec3f((center.x()+halfSize)*cellWorldSize, (center.y()+halfSize)*cellWorldSize, maxZ));
-                node->setBoundingBox(boundingBox);
-            }
+            // We arrived at a leaf.
+            // Since the tree is used for LOD level selection instead of culling, we do not need to load an actual height data here.
+            float minZ = -std::numeric_limits<float>::max();
+            float maxZ = std::numeric_limits<float>::max();
+            float cellWorldSize = mStorage->getCellWorldSize();
+            osg::BoundingBox boundingBox(osg::Vec3f((center.x()-halfSize)*cellWorldSize, (center.y()-halfSize)*cellWorldSize, minZ),
+                                    osg::Vec3f((center.x()+halfSize)*cellWorldSize, (center.y()+halfSize)*cellWorldSize, maxZ));
+            node->setBoundingBox(boundingBox);
             return node;
         }
         else
@@ -360,7 +359,7 @@ void QuadTreeWorld::accept(osg::NodeVisitor &nv)
                 mRootNode->traverseTo(vd, 1, osg::Vec2f(x+0.5,y+0.5));
             }
             else
-                mRootNode->traverse(vd, &nv, cv->getViewPoint(), true, mViewDistance);
+                mRootNode->traverse(vd, cv->getViewPoint(), mViewDistance);
         }
         else
         {
@@ -376,9 +375,9 @@ void QuadTreeWorld::accept(osg::NodeVisitor &nv)
             mRootNode->intersect(vd, terrainIntersector);
         }
     }
-    else if (isCullVisitor)
+
+    if (isCullVisitor)
     {
-        // view point is the same, but must still update visible status in case the camera has rotated
         for (unsigned int i=0; i<vd->getNumEntries(); ++i)
         {
             ViewData::Entry& entry = vd->getEntry(i);
@@ -471,7 +470,7 @@ void QuadTreeWorld::preload(View *view, const osg::Vec3f &viewPoint, std::atomic
 
     ViewData* vd = static_cast<ViewData*>(view);
     vd->setViewPoint(viewPoint);
-    mRootNode->traverse(vd, nullptr, viewPoint, false, mViewDistance);
+    mRootNode->traverse(vd, viewPoint, mViewDistance);
 
     for (unsigned int i=0; i<vd->getNumEntries() && !abort; ++i)
     {