FGFS-4.1/OpenSceneGraph
4
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Implement hierachy culling in KdTree::intersect(..)

Browse Source
This commit is contained in:
Robert Osfield
2008-07-07 20:27:56 +00:00
parent f1db402f2b
commit 134c86c2d5
3 changed files with 291 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files

245
src/osg/KdTree.cpp
View File

@@ -19,7 +19,7 @@
using namespace osg;
//#define VERBOSE_OUTPUT
// #define VERBOSE_OUTPUT
////////////////////////////////////////////////////////////////////////////////
//
@@ -57,6 +57,17 @@ struct TriangleIndicesCollector
//
// KdTree
KdTree::BuildOptions::BuildOptions():
_numVerticesProcessed(0),
_targetNumTrianglesPerLeaf(8),
_maxNumLevels(24)
{
}
////////////////////////////////////////////////////////////////////////////////
//
// KdTree
KdTree::KdTree()
{
}
@@ -117,6 +128,29 @@ bool KdTree::build(BuildOptions& options, osg::Geometry* geometry)
osg::BoundingBox bb = _bb;
int nodeNum = divide(options, bb, leafNum, 0);
#if 0
for(KdLeafList::iterator itr = _kdLeaves.begin();
itr != _kdLeaves.end();
++itr)
{
KdLeaf& leaf = *itr;
leaf.bb.init();
int iend = leaf.first+leaf.second;
for(int i=leaf.first; i<iend; ++i)
{
const Triangle& tri = _triangles[_primitiveIndices[i]];
const osg::Vec3& v1 = (*_vertices)[tri._p1];
const osg::Vec3& v2 = (*_vertices)[tri._p2];
const osg::Vec3& v3 = (*_vertices)[tri._p3];
leaf.bb.expandBy(v1);
leaf.bb.expandBy(v2);
leaf.bb.expandBy(v3);
}
// osg::notify(osg::NOTICE)<<"leaf.bb.min("<<leaf.bb._min<<") max("<<leaf.bb._max<<")"<<std::endl;
}
#endif
#ifdef VERBOSE_OUTPUT
osg::notify(osg::NOTICE)<<"Root nodeNum="<<nodeNum<<std::endl;
#endif
@@ -186,7 +220,25 @@ int KdTree::divide(BuildOptions& options, osg::BoundingBox& bb, int nodeIndex, u
else
{
if (getLeaf(nodeIndex).second<=options._targetNumTrianglesPerLeaf) return nodeIndex;
if (getLeaf(nodeIndex).second<=options._targetNumTrianglesPerLeaf)
{
// leaf is done, now compute bound on it.
KdLeaf& leaf = getLeaf(nodeIndex);
leaf.bb.init();
int iend = leaf.first+leaf.second;
for(int i=leaf.first; i<iend; ++i)
{
const Triangle& tri = _triangles[_primitiveIndices[i]];
const osg::Vec3& v1 = (*_vertices)[tri._p1];
const osg::Vec3& v2 = (*_vertices)[tri._p2];
const osg::Vec3& v3 = (*_vertices)[tri._p3];
leaf.bb.expandBy(v1);
leaf.bb.expandBy(v2);
leaf.bb.expandBy(v3);
}
return nodeIndex;
}
//osg::notify(osg::NOTICE)<<" divide leaf"<<std::endl;
@@ -292,6 +344,10 @@ int KdTree::divide(BuildOptions& options, osg::BoundingBox& bb, int nodeIndex, u
getNode(nodeNum).first = leftChildIndex;
getNode(nodeNum).second = rightChildIndex;
getNode(nodeNum).bb.init();
if (leftChildIndex!=0) getNode(nodeNum).bb.expandBy(getBoundingBox(leftChildIndex));
if (rightChildIndex!=0) getNode(nodeNum).bb.expandBy(getBoundingBox(rightChildIndex));
return nodeNum;
}
}
@@ -423,7 +479,7 @@ bool KdTree::intersect(const KdLeaf& leaf, const osg::Vec3& start, const osg::Ve
intersections.insert(intersection);
osg::notify(osg::NOTICE)<<" got intersection ("<<in<<") ratio="<<r<<std::endl;
// osg::notify(osg::NOTICE)<<" got intersection ("<<in<<") ratio="<<r<<std::endl;
intersects = true;
}
@@ -431,16 +487,187 @@ bool KdTree::intersect(const KdLeaf& leaf, const osg::Vec3& start, const osg::Ve
return intersects;
}
bool KdTree::intersect(const KdNode& node, const osg::Vec3& start, const osg::Vec3& end, const osg::Vec3& s, const osg::Vec3& e, LineSegmentIntersections& intersections) const
{
//osg::notify(osg::NOTICE)<<" Intersect "<<&node<<std::endl;
//osg::Vec3 ls(start), le(end);
osg::Vec3 ls(s), le(e);
int numIntersectionsBefore = intersections.size();
if (intersectAndClip(ls, le, node.bb))
{
if (node.first>0) intersect(getNode(node.first), start, end, ls, le, intersections);
else if (node.first<0) intersect(getLeaf(node.first), start, end, intersections);
if (node.second>0) intersect(getNode(node.second), start, end, ls, le, intersections);
else if (node.second<0) intersect(getLeaf(node.second), start, end, intersections);
}
return numIntersectionsBefore != intersections.size();
}
bool KdTree::intersectAndClip(osg::Vec3& s, osg::Vec3& e, const osg::BoundingBox& bb) const
{
// compate s and e against the xMin to xMax range of bb.
if (s.x()<=e.x())
{
// trivial reject of segment wholely outside.
if (e.x()<bb.xMin()) return false;
if (s.x()>bb.xMax()) return false;
if (s.x()<bb.xMin())
{
// clip s to xMin.
s = s+(e-s)*(bb.xMin()-s.x())/(e.x()-s.x());
}
if (e.x()>bb.xMax())
{
// clip e to xMax.
e = s+(e-s)*(bb.xMax()-s.x())/(e.x()-s.x());
}
}
else
{
if (s.x()<bb.xMin()) return false;
if (e.x()>bb.xMax()) return false;
if (e.x()<bb.xMin())
{
// clip s to xMin.
e = s+(e-s)*(bb.xMin()-s.x())/(e.x()-s.x());
}
if (s.x()>bb.xMax())
{
// clip e to xMax.
s = s+(e-s)*(bb.xMax()-s.x())/(e.x()-s.x());
}
}
// compate s and e against the yMin to yMax range of bb.
if (s.y()<=e.y())
{
// trivial reject of segment wholely outside.
if (e.y()<bb.yMin()) return false;
if (s.y()>bb.yMax()) return false;
if (s.y()<bb.yMin())
{
// clip s to yMin.
s = s+(e-s)*(bb.yMin()-s.y())/(e.y()-s.y());
}
if (e.y()>bb.yMax())
{
// clip e to yMax.
e = s+(e-s)*(bb.yMax()-s.y())/(e.y()-s.y());
}
}
else
{
if (s.y()<bb.yMin()) return false;
if (e.y()>bb.yMax()) return false;
if (e.y()<bb.yMin())
{
// clip s to yMin.
e = s+(e-s)*(bb.yMin()-s.y())/(e.y()-s.y());
}
if (s.y()>bb.yMax())
{
// clip e to yMax.
s = s+(e-s)*(bb.yMax()-s.y())/(e.y()-s.y());
}
}
// compate s and e against the zMin to zMax range of bb.
if (s.z()<=e.z())
{
// trivial reject of segment wholely outside.
if (e.z()<bb.zMin()) return false;
if (s.z()>bb.zMax()) return false;
if (s.z()<bb.zMin())
{
// clip s to zMin.
s = s+(e-s)*(bb.zMin()-s.z())/(e.z()-s.z());
}
if (e.z()>bb.zMax())
{
// clip e to zMax.
e = s+(e-s)*(bb.zMax()-s.z())/(e.z()-s.z());
}
}
else
{
if (s.z()<bb.zMin()) return false;
if (e.z()>bb.zMax()) return false;
if (e.z()<bb.zMin())
{
// clip s to zMin.
e = s+(e-s)*(bb.zMin()-s.z())/(e.z()-s.z());
}
if (s.z()>bb.zMax())
{
// clip e to zMax.
s = s+(e-s)*(bb.zMax()-s.z())/(e.z()-s.z());
}
}
// osg::notify(osg::NOTICE)<<"clampped segment "<<s<<" "<<e<<std::endl;
// if (s==e) return false;
return true;
}
bool KdTree::intersect(const osg::Vec3& start, const osg::Vec3& end, LineSegmentIntersections& intersections) const
{
// osg::notify(osg::NOTICE)<<"KdTree::intersect("<<start<<","<<end<<")"<<std::endl;
//osg::notify(osg::NOTICE)<<"KdTree::intersect("<<start<<","<<end<<")"<<std::endl;
bool intersects = false;
for(KdLeafList::const_iterator itr = _kdLeaves.begin();
itr != _kdLeaves.end();
++itr)
int option = 2;
switch(option)
{
if (intersect(*itr, start, end, intersections)) intersects = true;
case(0):
{
for(KdLeafList::const_iterator itr = _kdLeaves.begin();
itr != _kdLeaves.end();
++itr)
{
if (intersect(*itr, start, end, intersections)) intersects = true;
}
break;
}
case(1):
{
for(KdLeafList::const_iterator itr = _kdLeaves.begin();
itr != _kdLeaves.end();
++itr)
{
osg::Vec3 s(start), e(end);
if (intersectAndClip(s,e,itr->bb))
{
if (intersect(*itr, start, end, intersections)) intersects = true;
}
}
break;
}
case(2):
{
//osg::notify(osg::NOTICE)<<"_kdNodes.size()="<<_kdNodes.size()<<std::endl;
osg::Vec3 s(start), e(end);
if (intersect(getNode(0), start, end, s,e, intersections)) intersects = true;
break;
}
}
return intersects;