Fixes to the LWO to better handle 3 and 4 vertex polygons.

Added an extra pass into the Optimizer's merging of geometry primitives so
it convertex 3 and 4 vertex polygons into triangles and quads respectively.

include/osg/Primitive

@@ -127,6 +127,8 @@ class Primitive : public Object
         
         virtual void offsetIndices(int offset) = 0;
         
+        virtual unsigned int getNumIndices() = 0;
+
     protected:
 
         Type    _primitiveType;
@@ -178,6 +180,8 @@ class SG_EXPORT DrawArrays : public Primitive
         
         virtual void offsetIndices(int offset) { _first += offset; }
 
+        virtual unsigned int getNumIndices() { return _count; }
+
     protected:
 
         GLint   _first;
@@ -229,6 +233,8 @@ class SG_EXPORT DrawArrayLengths : public Primitive, public VectorSizei
         
         virtual void offsetIndices(int offset) { _first += offset; }
 
+        virtual unsigned int getNumIndices();
+
     protected:
 
         GLint   _first;
@@ -269,6 +275,8 @@ class SG_EXPORT DrawElementsUByte : public Primitive, public VectorUByte
         virtual void accept(Drawable::PrimitiveFunctor& functor);
 
         virtual void offsetIndices(int offset);
+
+        virtual unsigned int getNumIndices() { return size(); }
 };
 
 
@@ -307,6 +315,8 @@ class SG_EXPORT DrawElementsUShort : public Primitive, public VectorUShort
         virtual void accept(Drawable::PrimitiveFunctor& functor);
 
         virtual void offsetIndices(int offset);
+
+        virtual unsigned int getNumIndices() { return size(); }
 };
 
 class SG_EXPORT DrawElementsUInt : public Primitive, public VectorUInt
@@ -344,6 +354,8 @@ class SG_EXPORT DrawElementsUInt : public Primitive, public VectorUInt
         virtual void accept(Drawable::PrimitiveFunctor& functor);
 
         virtual void offsetIndices(int offset);
+
+        virtual unsigned int getNumIndices() { return size(); }
 };
 
 // backwards compatibility with first incarnation of DrawElements nameing convention.

src/osg/Primitive.cpp

@@ -36,6 +36,17 @@ void DrawArrayLengths::accept(Drawable::PrimitiveFunctor& functor)
     }
 }
 
+unsigned int DrawArrayLengths::getNumIndices()
+{
+    unsigned int count = 0;
+    for(VectorSizei::iterator itr=begin();
+        itr!=end();
+        ++itr)
+    {
+        count += *itr;
+    }
+    return count;
+}
 
 
 void DrawElementsUByte::draw() const 

src/osgPlugins/lwo/ReaderWriterLWO.cpp

@@ -198,7 +198,30 @@ osgDB::ReaderWriter::ReadResult ReaderWriterLWO::readNode_LWO1(const std::string
         {
             GeometryCollection& gc = mtgcm[face.material];
             
-            gc._geom->addPrimitive(osgNew osg::DrawArrays(osg::Primitive::POLYGON,gc._coordCount,face.index_cnt));
+            osg::Primitive::Mode mode;
+            switch(face.index_cnt)
+            {
+                case(0):
+                    mode = osg::Primitive::POINTS;
+                    break;
+                case(1):
+                    mode = osg::Primitive::POINTS;
+                    break;
+                case(2):
+                    mode = osg::Primitive::LINES;
+                    break;
+                case(3):
+                    mode = osg::Primitive::TRIANGLES;
+                    break;
+                case(4):
+                    mode = osg::Primitive::QUADS;
+                    break;
+                default:
+                    mode = osg::Primitive::POLYGON;
+                    break;
+            }
+                        
+            gc._geom->addPrimitive(osgNew osg::DrawArrays(mode,gc._coordCount,face.index_cnt));
             gc._coordCount += face.index_cnt;
 
             // From the spec_low.lxt :
@@ -239,7 +262,7 @@ osgDB::ReaderWriter::ReadResult ReaderWriterLWO::readNode_LWO1(const std::string
         if (gc._geom)
         {
             
-            //tesselator.retesselatePolygons(*gc._geom);
+            tesselator.retesselatePolygons(*gc._geom);
         
             smoother.smooth(*gc._geom);
             

src/osgUtil/Optimizer.cpp

@@ -64,20 +64,12 @@ void Optimizer::optimize(osg::Node* node, unsigned int options)
 
     if (options & SHARE_DUPLICATE_STATE)
     {
-//     #if (defined(_MSC_VER) && _MSC_VER<1300 && !defined(_STLPORT_VERSION))
-//         osg::notify(osg::NOTICE)<<"Warning: this application was built with VisualStudio 6.0's native STL,"<<std::endl;
-//         osg::notify(osg::NOTICE)<<"         and due to bugs in VS's STL we are unable to run state optimizer."<<std::endl; 
-//         osg::notify(osg::NOTICE)<<"         This may impare performance significantly for larger models."<<std::endl; 
-//         osg::notify(osg::NOTICE)<<"         It is recommend that one compiles against STLport or use "<<std::endl; 
-//         osg::notify(osg::NOTICE)<<"         Visual Studio .NET compiler which also fix these VS 6.0 STL bugs "<<std::endl; 
-//     #else
         StateVisitor osv;
         node->accept(osv);
         osv.optimize();
 
         MergeGeometryVisitor mgv;
         node->accept(mgv);
-//     #endif
     }
 
 
@@ -1139,7 +1131,8 @@ struct LessGeometryPrimitiveType
 
 bool Optimizer::MergeGeometryVisitor::mergeGeode(osg::Geode& geode)
 {
-    if (geode.getNumDrawables()<2) return false;
+    if (geode.getNumDrawables()>=2)
+    {
     
         typedef std::vector<osg::Geometry*>                         DuplicateList;
         typedef std::map<osg::Geometry*,DuplicateList,LessGeometry> GeometryDuplicateMap;
@@ -1181,6 +1174,36 @@ bool Optimizer::MergeGeometryVisitor::mergeGeode(osg::Geode& geode)
                 }
             }
         }
+    }
+
+    // convert all polygon primitives which has 3 indices into TRIANGLES, 4 indices into QUADS.
+    unsigned int i;
+    for(i=0;i<geode.getNumDrawables();++i)
+    {
+        osg::Geometry* geom = dynamic_cast<osg::Geometry*>(geode.getDrawable(i));
+        if (geom)
+        {
+            osg::Geometry::PrimitiveList& primitives = geom->getPrimitiveList();
+            for(osg::Geometry::PrimitiveList::iterator itr=primitives.begin();
+                itr!=primitives.end();
+                ++itr)
+            {
+                osg::Primitive* prim = itr->get();
+                if (prim->getMode()==osg::Primitive::POLYGON)
+                {
+                    if (prim->getNumIndices()==3)
+                    {
+                        prim->setMode(osg::Primitive::TRIANGLES);
+                    }
+                    else if (prim->getNumIndices()==4)
+                    {
+                        prim->setMode(osg::Primitive::QUADS);
+                    }
+                }
+            }
+        }
+    }
+
 
     // now merge any compatible primtives.
     for(i=0;i<geode.getNumDrawables();++i)
@@ -1217,6 +1240,7 @@ bool Optimizer::MergeGeometryVisitor::mergeGeode(osg::Geode& geode)
 
                     if (combine)
                     {
+                    
                         switch(lhs->getType())
                         {
                         case(osg::Primitive::DrawArraysPrimitiveType):

src/osgUtil/Tesselator.cpp

@@ -38,6 +38,7 @@ void Tesselator::beginContour()
     if (_tobj)
     {
         gluTessBeginContour(_tobj);
+//        cout<<"begin"<<endl;
     }
 }
       
@@ -51,6 +52,7 @@ void Tesselator::addVertex(osg::Vec3* vertex)
         (*data)._v[1]=(*vertex)[1];
         (*data)._v[2]=(*vertex)[2];
         gluTessVertex(_tobj,data->_v,vertex);
+//        cout<<"\t"<<*vertex<<endl;
     }
 }
 
@@ -59,6 +61,7 @@ void Tesselator::endContour()
     if (_tobj)
     {
         gluTessEndContour(_tobj);
+//        cout<<"end"<<endl;
     }
 }