From bb804c2045061c892ae2ad5ba41091a1166481c6 Mon Sep 17 00:00:00 2001
From: blobfish <blobfish@gmx.com>
Date: Thu, 1 Jun 2017 15:25:38 -0400
Subject: [PATCH] osg: KdTree: encode original primitive index into
 _vertexIndices

---
 include/osg/KdTree | 21 +++++++++++++--------
 src/osg/KdTree.cpp |  1 +
 2 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/include/osg/KdTree b/include/osg/KdTree
index 12279334e..8ebe80bd0 100644
--- a/include/osg/KdTree
+++ b/include/osg/KdTree
@@ -69,41 +69,45 @@ class OSG_EXPORT KdTree : public osg::Shape
         inline unsigned int addPoint(unsigned int p0)
         {
             unsigned int i = _vertexIndices.size();
-            _primitiveIndices.push_back(i);
+            _vertexIndices.push_back(_primitiveIndices.size());
             _vertexIndices.push_back(1);
             _vertexIndices.push_back(p0);
+            _primitiveIndices.push_back(i);
             return i;
         }
         inline unsigned int addLine(unsigned int p0, unsigned int p1)
         {
             unsigned int i = _vertexIndices.size();
-            _primitiveIndices.push_back(i);
+            _vertexIndices.push_back(_primitiveIndices.size());
             _vertexIndices.push_back(2);
             _vertexIndices.push_back(p0);
             _vertexIndices.push_back(p1);
+            _primitiveIndices.push_back(i);
             return i;
         }
 
         inline unsigned int addTriangle(unsigned int p0, unsigned int p1, unsigned int p2)
         {
             unsigned int i = _vertexIndices.size();
-            _primitiveIndices.push_back(i);
+            _vertexIndices.push_back(_primitiveIndices.size());
             _vertexIndices.push_back(3);
             _vertexIndices.push_back(p0);
             _vertexIndices.push_back(p1);
             _vertexIndices.push_back(p2);
+            _primitiveIndices.push_back(i);
             return i;
         }
 
         inline unsigned int addQuad(unsigned int p0, unsigned int p1, unsigned int p2, unsigned int p3)
         {
             unsigned int i = _vertexIndices.size();
-            _primitiveIndices.push_back(i);
+            _vertexIndices.push_back(_primitiveIndices.size());
             _vertexIndices.push_back(4);
             _vertexIndices.push_back(p0);
             _vertexIndices.push_back(p1);
             _vertexIndices.push_back(p2);
             _vertexIndices.push_back(p3);
+            _primitiveIndices.push_back(i);
             return i;
         }
 
@@ -154,13 +158,14 @@ class OSG_EXPORT KdTree : public osg::Shape
                 for(int i=istart; i<iend; ++i)
                 {
                     unsigned int primitiveIndex = _primitiveIndices[i];
+                    unsigned int originalPIndex = _vertexIndices[primitiveIndex++];
                     unsigned int numVertices = _vertexIndices[primitiveIndex++];
                     switch(numVertices)
                     {
-                        case(1): functor.intersect(_vertices.get(), i, _vertexIndices[primitiveIndex]); break;
-                        case(2): functor.intersect(_vertices.get(), i, _vertexIndices[primitiveIndex], _vertexIndices[primitiveIndex+1]); break;
-                        case(3): functor.intersect(_vertices.get(), i, _vertexIndices[primitiveIndex], _vertexIndices[primitiveIndex+1], _vertexIndices[primitiveIndex+2]); break;
-                        case(4): functor.intersect(_vertices.get(), i, _vertexIndices[primitiveIndex], _vertexIndices[primitiveIndex+1], _vertexIndices[primitiveIndex+2], _vertexIndices[primitiveIndex+3]); break;
+                        case(1): functor.intersect(_vertices.get(), originalPIndex, _vertexIndices[primitiveIndex]); break;
+                        case(2): functor.intersect(_vertices.get(), originalPIndex, _vertexIndices[primitiveIndex], _vertexIndices[primitiveIndex+1]); break;
+                        case(3): functor.intersect(_vertices.get(), originalPIndex, _vertexIndices[primitiveIndex], _vertexIndices[primitiveIndex+1], _vertexIndices[primitiveIndex+2]); break;
+                        case(4): functor.intersect(_vertices.get(), originalPIndex, _vertexIndices[primitiveIndex], _vertexIndices[primitiveIndex+1], _vertexIndices[primitiveIndex+2], _vertexIndices[primitiveIndex+3]); break;
                         default : OSG_NOTICE<<"Warning: KdTree::intersect() encounted unsupported primitive size of "<<numVertices<<std::endl; break;
                     }
                 }
diff --git a/src/osg/KdTree.cpp b/src/osg/KdTree.cpp
index eeadfb816..9d03020e8 100644
--- a/src/osg/KdTree.cpp
+++ b/src/osg/KdTree.cpp
@@ -287,6 +287,7 @@ int BuildKdTree::divide(KdTree::BuildOptions& options, osg::BoundingBox& bb, int
             for(int i=istart; i<=iend; ++i)
             {
                 unsigned int primitiveIndex = _kdTree.getPrimitiveIndices()[_primitiveIndices[i]];
+                primitiveIndex++; //skip original Primitive index
                 unsigned int numPoints = _kdTree.getVertexIndices()[primitiveIndex++];
 
                 for(; numPoints>0; --numPoints)