Initial revision

src/osg/LOD.cpp

@@ -0,0 +1,130 @@
+#include "osg/LOD"
+#include "osg/Input"
+#include "osg/Output"
+#include "osg/Registry"
+
+#include <algorithm>
+
+using namespace osg;
+
+RegisterObjectProxy<LOD> g_LODProxy;
+
+void LOD::traverse(NodeVisitor& nv)
+{
+    switch(nv.getTraverseMode())
+    {
+    case(NodeVisitor::TRAVERSE_ALL_CHILDREN):
+        std::for_each(_children.begin(),_children.end(),NodeAcceptOp(nv));
+        break;
+    case(NodeVisitor::TRAVERSE_ACTIVE_CHILDREN):
+        if (_children.size()!=0) _children.front()->accept(nv);
+        break;
+    default:
+        break;
+    }
+}
+
+void LOD::setRange(unsigned int index, float range)
+{
+    if (index<_rangeList.size()) _rangeList[index] = range;
+    else while (index>=_rangeList.size()) _rangeList.push_back(range);
+
+    if (index<_rangeList2.size()) _rangeList2[index] = range*range;
+    else while (index>=_rangeList2.size()) _rangeList2.push_back(range*range);
+}
+
+int LOD::evaluate(const Vec3& eye_local, float bias)
+{
+	// For cache coherency, use _rangeList2 exclusively
+    if (_rangeList2.size()==0) return -1;
+
+	// Test distance-squared against the stored array of squared ranges
+    float LODRange = (eye_local-_center).length2()*bias;
+    if (LODRange<_rangeList2[0]) return -1;
+    
+    for(unsigned int i=0;i<_rangeList2.size()-1;++i)
+    {
+        if (_rangeList2[i]<=LODRange && LODRange<_rangeList2[i+1]) {
+            return i;
+        }
+    }
+    return -1;
+}
+
+bool LOD::readLocalData(Input& fr)
+{
+    bool iteratorAdvanced = false;
+
+    if (fr.matchSequence("Center %f %f %f"))
+    {
+
+        fr[1].getFloat(_center[0]);
+        fr[2].getFloat(_center[1]);
+        fr[3].getFloat(_center[2]);
+
+        iteratorAdvanced = true;
+        fr+=3;
+    }
+
+    bool matchFirst = false;
+    if ((matchFirst=fr.matchSequence("Ranges {")) || fr.matchSequence("Ranges %i {"))
+    {
+
+        // set up coordinates.
+        int entry = fr[0].getNoNestedBrackets();
+
+        if (matchFirst)
+        {
+            fr += 2;
+        }
+        else
+        {
+            //_rangeList.(capacity);
+            fr += 3;
+        }
+
+        float range;
+        while (!fr.eof() && fr[0].getNoNestedBrackets()>entry)
+        {
+            if (fr[0].getFloat(range))
+            {
+                ++fr;
+                _rangeList.push_back(range);
+                _rangeList2.push_back(range*range);
+            }
+            else
+            {
+                ++fr;
+            }
+        }
+
+        iteratorAdvanced = true;
+        ++fr;
+
+    }
+
+    if (Group::readLocalData(fr)) iteratorAdvanced = true;
+
+    return iteratorAdvanced;
+}
+
+
+bool LOD::writeLocalData(Output& fw)
+{
+    fw.indent() << "Center "<<_center[0] << " "<<_center[1] << " "<<_center[2] <<endl;
+
+    fw.indent() << "Ranges {"<<endl;
+    fw.moveIn();
+    for(RangeList::iterator riter = _rangeList.begin();
+                            riter != _rangeList.end();
+                            ++riter)
+    {
+        fw.indent() << (*riter) <<endl;
+    }
+    fw.moveOut();
+    fw.indent() << "}"<<endl;
+
+    Group::writeLocalData(fw);
+
+    return true;
+}