diff --git a/src/Lib/terragear/tg_accumulator.cxx b/src/Lib/terragear/tg_accumulator.cxx
index 11fbb0ba..9850b36f 100644
--- a/src/Lib/terragear/tg_accumulator.cxx
+++ b/src/Lib/terragear/tg_accumulator.cxx
@@ -14,6 +14,10 @@ tgPolygon tgAccumulator::Diff( const tgContour& subject )
         all_nodes.add( subject.GetNode(i) );
     }
 
+    for ( unsigned int i = 0; i < nodes.size(); i++ ) {
+        all_nodes.add( nodes[i] );
+    }
+
     unsigned int  num_hits = 0;
     tgRectangle box1 = subject.GetBoundingBox();
 
@@ -50,40 +54,6 @@ tgPolygon tgAccumulator::Diff( const tgContour& subject )
     return result;
 }
 
-void tgAccumulator::Add( const tgContour& subject )
-{
-    tgPolygon poly;
-    poly.AddContour( subject );
-
-    ClipperLib::Polygons clipper_subject = tgPolygon::ToClipper( poly );
-    accum.push_back( clipper_subject );
-}
-
-void tgAccumulator::ToShapefiles( const std::string& path, const std::string& layer_prefix, bool individual )
-{
-    char shapefile[32];
-    char layer[32];
-
-    if ( individual ) {
-        for (unsigned int i=0; i < accum.size(); i++) {
-            sprintf( layer, "%s_%d", layer_prefix.c_str(), i );
-            sprintf( shapefile, "accum_%d", i );
-            tgShapefile::FromClipper( accum[i], path, layer, std::string(shapefile) );
-        }
-    } else {
-        ClipperLib::Polygons clipper_result;
-        ClipperLib::Clipper  c;
-        c.Clear();
-
-        for ( unsigned int i=0; i<accum.size(); i++ ) {
-            c.AddPolygons(accum[i], ClipperLib::ptSubject);
-        }
-        c.Execute( ClipperLib::ctUnion, clipper_result, ClipperLib::pftNonZero, ClipperLib::pftNonZero);
-
-        tgShapefile::FromClipper( clipper_result, path, layer_prefix, "accum" );
-    }
-}
-
 tgPolygon tgAccumulator::Diff( const tgPolygon& subject )
 {
     tgPolygon result;
@@ -96,6 +66,10 @@ tgPolygon tgAccumulator::Diff( const tgPolygon& subject )
         }
     }
 
+    for ( unsigned int i = 0; i < nodes.size(); i++ ) {
+        all_nodes.add( nodes[i] );
+    }
+
     unsigned int  num_hits = 0;
     tgRectangle box1 = subject.GetBoundingBox();
 
@@ -137,8 +111,54 @@ tgPolygon tgAccumulator::Diff( const tgPolygon& subject )
     return result;
 }
 
+void tgAccumulator::Add( const tgContour& subject )
+{
+    tgPolygon poly;
+
+    // Add the nodes
+    for ( unsigned int i = 0; i < subject.GetSize(); ++i ) {
+        nodes.add( subject.GetNode(i) );
+    }
+
+    poly.AddContour( subject );
+
+    ClipperLib::Polygons clipper_subject = tgPolygon::ToClipper( poly );
+    accum.push_back( clipper_subject );
+}
+
 void tgAccumulator::Add( const tgPolygon& subject )
 {
+    for ( unsigned int i = 0; i < subject.Contours(); ++i ) {
+        for ( unsigned int j = 0; j < subject.ContourSize( i ); ++j ) {
+            nodes.add( subject.GetNode(i, j) );
+        }
+    }
+
     ClipperLib::Polygons clipper_subject = tgPolygon::ToClipper( subject );
     accum.push_back( clipper_subject );
 }
+
+void tgAccumulator::ToShapefiles( const std::string& path, const std::string& layer_prefix, bool individual )
+{
+    char shapefile[32];
+    char layer[32];
+
+    if ( individual ) {
+        for (unsigned int i=0; i < accum.size(); i++) {
+            sprintf( layer, "%s_%d", layer_prefix.c_str(), i );
+            sprintf( shapefile, "accum_%d", i );
+            tgShapefile::FromClipper( accum[i], path, layer, std::string(shapefile) );
+        }
+    } else {
+        ClipperLib::Polygons clipper_result;
+        ClipperLib::Clipper  c;
+        c.Clear();
+
+        for ( unsigned int i=0; i<accum.size(); i++ ) {
+            c.AddPolygons(accum[i], ClipperLib::ptSubject);
+        }
+        c.Execute( ClipperLib::ctUnion, clipper_result, ClipperLib::pftNonZero, ClipperLib::pftNonZero);
+
+        tgShapefile::FromClipper( clipper_result, path, layer_prefix, "accum" );
+    }
+}
\ No newline at end of file
diff --git a/src/Lib/terragear/tg_accumulator.hxx b/src/Lib/terragear/tg_accumulator.hxx
index 5199c64b..3fc86e29 100644
--- a/src/Lib/terragear/tg_accumulator.hxx
+++ b/src/Lib/terragear/tg_accumulator.hxx
@@ -20,6 +20,7 @@ private:
     typedef std::vector < ClipperLib::Polygons > clipper_polygons_list;
 
     clipper_polygons_list   accum;
+    UniqueSGGeodSet         nodes;
 };
 
 #endif // _TGACCUMULATOR_HXX
\ No newline at end of file
diff --git a/src/Lib/terragear/tg_chopper.cxx b/src/Lib/terragear/tg_chopper.cxx
index cd5b3b3d..2b27e14b 100644
--- a/src/Lib/terragear/tg_chopper.cxx
+++ b/src/Lib/terragear/tg_chopper.cxx
@@ -45,7 +45,7 @@ tgPolygon tgChopper::Clip( const tgPolygon& subject,
     base.AddNode( 0, SGGeod::fromDeg( max.getLongitudeDeg(), max.getLatitudeDeg()) );
     base.AddNode( 0, SGGeod::fromDeg( min.getLongitudeDeg(), max.getLatitudeDeg()) );
 
-    result = tgPolygon::Intersect( base, subject );
+    result = tgPolygon::Intersect( subject, base );    
     if ( result.Contours() > 0 ) {
         if ( subject.GetPreserve3D() ) {
             result.InheritElevations( subject );
@@ -138,21 +138,21 @@ void tgChopper::Add( const tgPolygon& subject, const std::string& type )
             clip_row.AddNode( 0, SGGeod::fromDeg( 180.0, clip_top)    );
             clip_row.AddNode( 0, SGGeod::fromDeg(-180.0, clip_top)    );
 
-            clipped = tgPolygon::Intersect( clip_row, subject );
+            clipped = tgPolygon::Intersect( subject, clip_row );
             if ( clipped.TotalNodes() > 0 ) {
 
-            if ( subject.GetPreserve3D() ) {
-                clipped.InheritElevations( subject );
-                clipped.SetPreserve3D( true );
-            }
-            clipped.SetTexParams( subject.GetTexParams() );
-            if ( subject.GetTexMethod() == TG_TEX_BY_GEODE ) {
-                // need to set center latitude for geodetic texturing
-                clipped.SetTexMethod( TG_TEX_BY_GEODE, b_clip.get_center_lat() );
-            }
-            clipped.SetFlag(type);
+                if ( subject.GetPreserve3D() ) {
+                    clipped.InheritElevations( subject );
+                    clipped.SetPreserve3D( true );
+                }
+                clipped.SetTexParams( subject.GetTexParams() );
+                if ( subject.GetTexMethod() == TG_TEX_BY_GEODE ) {
+                    // need to set center latitude for geodetic texturing
+                    clipped.SetTexMethod( TG_TEX_BY_GEODE, b_clip.get_center_lat() );
+                }
+                clipped.SetFlag(type);
 
-            ClipRow( clipped, b_clip.get_center_lat(), type );
+                ClipRow( clipped, b_clip.get_center_lat(), type );
 
 #if 0
                 {
diff --git a/src/Lib/terragear/tg_contour.cxx b/src/Lib/terragear/tg_contour.cxx
index 35ba70c6..fe106a7a 100644
--- a/src/Lib/terragear/tg_contour.cxx
+++ b/src/Lib/terragear/tg_contour.cxx
@@ -456,6 +456,12 @@ tgPolygon tgContour::Union( const tgContour& subject, tgPolygon& clip )
         all_nodes.add( subject.GetNode(i) );
     }
 
+    for ( unsigned int i = 0; i < clip.Contours(); ++i ) {
+        for ( unsigned int j = 0; j < clip.ContourSize( i ); ++j ) {
+            all_nodes.add( clip.GetNode(i, j) );
+        }
+    }
+
     ClipperLib::Polygon  clipper_subject = tgContour::ToClipper( subject );
     ClipperLib::Polygons clipper_clip    = tgPolygon::ToClipper( clip );
     ClipperLib::Polygons clipper_result;
@@ -481,6 +487,12 @@ tgPolygon tgContour::Diff( const tgContour& subject, tgPolygon& clip )
     for ( unsigned int i = 0; i < subject.GetSize(); ++i ) {
         all_nodes.add( subject.GetNode(i) );
     }
+    
+    for ( unsigned int i = 0; i < clip.Contours(); ++i ) {
+        for ( unsigned int j = 0; j < clip.ContourSize( i ); ++j ) {
+            all_nodes.add( clip.GetNode(i, j) );
+        }
+    }
 
     ClipperLib::Polygon clipper_subject = tgContour::ToClipper( subject );
     ClipperLib::Polygons clipper_clip    = tgPolygon::ToClipper( clip );
@@ -508,6 +520,10 @@ tgPolygon tgContour::Intersect( const tgContour& subject, const tgContour& clip
         all_nodes.add( subject.GetNode(i) );
     }
 
+    for ( unsigned int i = 0; i < clip.GetSize(); ++i ) {
+        all_nodes.add( clip.GetNode(i) );
+    }
+
     ClipperLib::Polygon  clipper_subject = tgContour::ToClipper( subject );
     ClipperLib::Polygon  clipper_clip    = tgContour::ToClipper( clip );
     ClipperLib::Polygons clipper_result;
diff --git a/src/Lib/terragear/tg_polygon_clip.cxx b/src/Lib/terragear/tg_polygon_clip.cxx
index 04b996be..e3db6c7a 100644
--- a/src/Lib/terragear/tg_polygon_clip.cxx
+++ b/src/Lib/terragear/tg_polygon_clip.cxx
@@ -24,6 +24,12 @@ tgPolygon tgPolygon::Union( const tgPolygon& subject, tgPolygon& clip )
         }
     }
 
+    for ( unsigned int i = 0; i < clip.Contours(); ++i ) {
+        for ( unsigned int j = 0; j < clip.ContourSize( i ); ++j ) {
+            all_nodes.add( clip.GetNode(i, j) );
+        }
+    }
+
     ClipperLib::Polygons clipper_subject = tgPolygon::ToClipper( subject );
     ClipperLib::Polygons clipper_clip    = tgPolygon::ToClipper( clip );
     ClipperLib::Polygons clipper_result;
@@ -100,6 +106,12 @@ tgPolygon tgPolygon::Diff( const tgPolygon& subject, tgPolygon& clip )
         }
     }
 
+    for ( unsigned int i = 0; i < clip.Contours(); ++i ) {
+        for ( unsigned int j = 0; j < clip.ContourSize( i ); ++j ) {
+            all_nodes.add( clip.GetNode(i, j) );
+        }
+    }
+
     ClipperLib::Polygons clipper_subject = tgPolygon::ToClipper( subject );
     ClipperLib::Polygons clipper_clip    = tgPolygon::ToClipper( clip );
     ClipperLib::Polygons clipper_result;
@@ -131,6 +143,12 @@ tgPolygon tgPolygon::Intersect( const tgPolygon& subject, const tgPolygon& clip
         }
     }
 
+    for ( unsigned int i = 0; i < clip.Contours(); ++i ) {
+        for ( unsigned int j = 0; j < clip.ContourSize( i ); ++j ) {
+            all_nodes.add( clip.GetNode(i, j) );
+        }
+    }
+
     ClipperLib::Polygons clipper_subject = tgPolygon::ToClipper( subject );
     ClipperLib::Polygons clipper_clip    = tgPolygon::ToClipper( clip );
     ClipperLib::Polygons clipper_result;
diff --git a/src/Lib/terragear/tg_polygon_tesselate.cxx b/src/Lib/terragear/tg_polygon_tesselate.cxx
index 503e3b29..6a346ef5 100644
--- a/src/Lib/terragear/tg_polygon_tesselate.cxx
+++ b/src/Lib/terragear/tg_polygon_tesselate.cxx
@@ -128,7 +128,9 @@ void tgPolygon::Tesselate( const std::vector<SGGeod>& extra )
             tg_insert_polygon(cdt, poly);
         }
 
-        
+        /* make conforming - still has an issue, and can't be compiled with exact_construction kernel */
+        // CGAL::make_conforming_Delaunay_2( cdt );
+
         tg_mark_domains( cdt );
 
         int count=0;