cleanup and use C++ version of FLT_MAX

components/terrain/quadtreeworld.cpp

@@ -2,6 +2,7 @@
 
 #include <osgUtil/CullVisitor>
 
+#include <limits>
 #include <sstream>
 
 #include <components/misc/constants.hpp>
@@ -311,11 +312,11 @@ void updateWaterCullingView(HeightCullCallback* callback, ViewData* vd, osgUtil:
 {
     if (!(cv->getTraversalMask() & callback->getCullMask()))
         return;
-    float lowZ = FLT_MAX;
+    float lowZ = std::numeric_limits<float>::max();
     float highZ = callback->getHighZ();
     if (cv->getEyePoint().z() <= highZ || outofworld)
     {
-        callback->setLowZ(-FLT_MAX);
+        callback->setLowZ(-std::numeric_limits<float>::max());
         return;
     }
     cv->pushCurrentMask();

components/terrain/world.hpp

@@ -7,9 +7,9 @@
 #include <osg/NodeCallback>
 
 #include <atomic>
+#include <limits>
 #include <memory>
 #include <set>
-#include <atomic>
 
 #include "defs.hpp"
 #include "cellborder.hpp"
@@ -43,7 +43,7 @@ namespace Terrain
 class HeightCullCallback : public osg::NodeCallback
 {
 public:
-    HeightCullCallback() : mLowZ(-FLT_MAX), mHighZ(FLT_MAX), mMask(~0) {}
+    HeightCullCallback() : mLowZ(-std::numeric_limits<float>::max()), mHighZ(std::numeric_limits<float>::max()), mMask(~0) {}
 
     void setLowZ(float z)
     {