From Trajce Nikolov, "attached is a fix for the txp loader (in TileMapper). The code was giving wrong parent tile ids using the stack - I implemented differnt approach for that"

src/osgPlugins/txp/TileMapper.cpp

@@ -243,9 +243,6 @@ bool TileMapper::canParentBeTraversed(const TileIdentifier& tid) const
     // note tile here, is tid's parent.
     const TileStack::value_type* tile = (ts.size()>=2) ? &ts[ts.size()-2] : 0;
 
-    // note parent here, is tid's parents parent.
-    const TileStack::value_type* parent = (ts.size()>=3) ? &ts[ts.size()-3] : 0;
-    
     if (!tile)
     {
         // no self!!! so we can descend safely?!! shouldn't ever get here.
@@ -253,6 +250,12 @@ bool TileMapper::canParentBeTraversed(const TileIdentifier& tid) const
         return true;
     }
 
+
+    // note parent here, is tid's parents parent.
+    const TileStack::value_type* parent = (ts.size()>=3) ? &ts[ts.size()-3] : 0;
+    
+    
+
     if (!parent)
     {
         // no parent so we can descend safely.
@@ -271,14 +274,22 @@ bool TileMapper::canParentBeTraversed(const TileIdentifier& tid) const
         return true;
     }
 
+    // FIXME: this guy gives us wrong parent
+    // Nick 2010/12/12
+#if 0
     const TileIdentifier& parent_tid = parent->first;
+#else
+    TileIdentifier parent_tid(tid.x/2,tid.y/2,tid.lod-1);
+#endif
     
     bool parentHasNorthNeighour = _tileMap.count(TileIdentifier(parent_tid.x,parent_tid.y+1,parent_tid.lod))!=0;
     bool parentHasEastNeighour = _tileMap.count(TileIdentifier(parent_tid.x+1,parent_tid.y,parent_tid.lod))!=0;
     bool parentHasSouthNeighour = _tileMap.count(TileIdentifier(parent_tid.x,parent_tid.y-1,parent_tid.lod))!=0;
     bool parentHasWestNeighour = _tileMap.count(TileIdentifier(parent_tid.x-1,parent_tid.y,parent_tid.lod))!=0;
     
-
+    // FIXME: this guy gives us wrong parent
+    // Nick 2010/12/12
+#if 0
     // identify whether the tile is a NE/SE/SW/NW tile relative to its parent.
     osg::Vec3 delta = tile->second->getBound().center() - parent->second->getBound().center();
     
@@ -308,6 +319,37 @@ bool TileMapper::canParentBeTraversed(const TileIdentifier& tid) const
             return (!parentHasSouthNeighour && !parentHasWestNeighour);
         }
     }
+#else
+    // identify whether the tile is a NE/SE/SW/NW tile relative to its parent.
+    osg::Vec3 delta(tid.x%2,tid.y%2,0);
+
+    if (delta.y()>0.0f) // noth side
+    {
+        if (delta.x()>0.0f)
+        {
+            // NE, only traverse if our parent doesn't have any neighbours to the north or east.
+            return (!parentHasNorthNeighour && !parentHasEastNeighour);
+        }
+        else 
+        {
+            // NW, only traverse if our parent doesn't have any neighbours to the north or west.
+            return (!parentHasNorthNeighour && !parentHasWestNeighour);
+        }
+    }
+    else // south side
+    {
+        if (delta.x()>0.0f)
+        {
+            // SE, only traverse if our parent doesn't have any neighbours to the south or east.
+            return (!parentHasSouthNeighour && !parentHasEastNeighour);
+        }
+        else 
+        {
+            // SW, only traverse if our parent doesn't have any neighbours to the south or west.
+            return (!parentHasSouthNeighour && !parentHasWestNeighour);
+        }
+    }
+#endif
 }
 
 void TileMapper::checkValidityOfAllVisibleTiles()
@@ -385,7 +427,6 @@ void TileMapper::checkValidityOfAllVisibleTiles()
 #endif
 
 }
-
 bool TileMapper::isTileNeighbourALowerLODLevel(const TileIdentifier& tid, int dx, int dy) const
 {
     if (_tileMap.count(TileIdentifier(tid.x+dx,tid.y+dy,tid.lod))!=0)
@@ -418,6 +459,10 @@ bool TileMapper::isTileNeighbourALowerLODLevel(const TileIdentifier& tid, int dx
         return false;
     }
 
+    // FIXME: this guy gives us wrong parent
+    // Nick 2010/12/12
+#if 0
+
     // note parent here, is tid's parents parent.
     const TileStack::value_type* parent = (ts.size()>=2) ? &ts[ts.size()-2] : 0;
     
@@ -428,6 +473,11 @@ bool TileMapper::isTileNeighbourALowerLODLevel(const TileIdentifier& tid, int dx
     }
 
     const TileIdentifier& parent_tid = parent->first;
+#else
+
+    TileIdentifier parent_tid(tid.x/2,tid.y/2,tid.lod-1);
+
+#endif
 
     bool parentHasNorthNeighour = _tileMap.count(TileIdentifier(parent_tid.x,  parent_tid.y+1,parent_tid.lod))!=0;
     bool parentHasEastNeighour  = _tileMap.count(TileIdentifier(parent_tid.x+1,parent_tid.y,  parent_tid.lod))!=0;
@@ -436,6 +486,10 @@ bool TileMapper::isTileNeighbourALowerLODLevel(const TileIdentifier& tid, int dx
     
 
     // identify whether the tile is a NE/SE/SW/NW tile relative to its parent.
+
+        // FIXME: wrong parent wrong values
+        // Nick 2010/12/12
+#if 0
     osg::Vec3 delta = tile->second->getBound().center() - parent->second->getBound().center();
     
     if (delta.y()>=0.0f) // noth side
@@ -476,6 +530,48 @@ bool TileMapper::isTileNeighbourALowerLODLevel(const TileIdentifier& tid, int dx
                 return parentHasWestNeighour;
         }
     }
+#else
+    osg::Vec3 delta(tid.x%2,tid.y%2,0);
+
+    if (delta.y()>0.0f) // noth side
+    {
+        if (delta.x()>0.0f)
+        {
+            // NE
+            if (dy==1)
+                return parentHasNorthNeighour;
+            else if (dx==1)
+                return parentHasEastNeighour;
+        }
+        else 
+        {
+            // NW
+            if (dy==1)
+                return parentHasNorthNeighour;
+            else if (dx==-1)
+                return parentHasWestNeighour;
+        }
+    }
+    else // south side
+    {
+        if (delta.x()>0.0f)
+        {
+            // SE
+            if (dy==-1)
+                return parentHasSouthNeighour;
+            else if (dx==1)
+                return parentHasEastNeighour;
+        }
+        else 
+        {
+            // SW
+            if (dy==-1)
+                return parentHasSouthNeighour;
+            else if (dx==-1)
+                return parentHasWestNeighour;
+        }
+    }
+#endif
 
     return false;
 }