irrlicht/source/Irrlicht/Octree.h

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// Copyright (C) 2002-2012 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h
#ifndef __C_OCTREE_H_INCLUDED__
#define __C_OCTREE_H_INCLUDED__
#include "SViewFrustum.h"
#include "S3DVertex.h"
#include "aabbox3d.h"
#include "irrArray.h"
#include "CMeshBuffer.h"
/**
Flags for Octree
*/
//! bypass full invisible/visible test
#define OCTREE_PARENTTEST
namespace irr
{
//! template octree.
/** T must be a vertex type which has a member
called .Pos, which is a core::vertex3df position. */
template <class T>
class Octree
{
public:
// TODO: Using reference counted class on the stack.
// Reason is likely that it really costs speed here otherwise.
// But doing so prevents using VBO's with octrees.
// Also it's just a bad idea, for example this is the reason
// we can't make the copy-constructor private for IReferenceCounted.
// So would be nice to figure out how to put this on heap (and check
// if it's maybe cheap enough) or maybe stop using CMeshBuffer here.
struct SMeshChunk : public scene::CMeshBuffer<T>
{
SMeshChunk ()
: scene::CMeshBuffer<T>(), MaterialId(0)
{
scene::CMeshBuffer<T>::grab();
}
virtual ~SMeshChunk ()
{
//removeAllHardwareBuffers
}
s32 MaterialId;
};
struct SIndexChunk
{
core::array<u16> Indices;
s32 MaterialId;
};
struct SIndexData
{
u16* Indices;
s32 CurrentSize;
s32 MaxSize;
};
//! Constructor
Octree(const core::array<SMeshChunk>& meshes, s32 minimalPolysPerNode=128) :
IndexData(0), IndexDataCount(meshes.size()), NodeCount(0)
{
IndexData = new SIndexData[IndexDataCount];
// construct array of all indices
core::array<SIndexChunk>* indexChunks = new core::array<SIndexChunk>;
indexChunks->reallocate(meshes.size());
for (u32 i=0; i!=meshes.size(); ++i)
{
IndexData[i].CurrentSize = 0;
IndexData[i].MaxSize = meshes[i].Indices.size();
IndexData[i].Indices = new u16[IndexData[i].MaxSize];
indexChunks->push_back(SIndexChunk());
SIndexChunk& tic = indexChunks->getLast();
tic.MaterialId = meshes[i].MaterialId;
tic.Indices = meshes[i].Indices;
}
// create tree
Root = new OctreeNode(NodeCount, 0, meshes, indexChunks, minimalPolysPerNode);
}
//! returns all ids of polygons partially or fully enclosed
//! by this bounding box.
void calculatePolys(const core::aabbox3d<f32>& box)
{
for (u32 i=0; i!=IndexDataCount; ++i)
IndexData[i].CurrentSize = 0;
Root->getPolys(box, IndexData, 0);
}
//! returns all ids of polygons partially or fully enclosed
//! by a view frustum.
void calculatePolys(const scene::SViewFrustum& frustum)
{
for (u32 i=0; i!=IndexDataCount; ++i)
IndexData[i].CurrentSize = 0;
Root->getPolys(frustum, IndexData, 0);
}
const SIndexData* getIndexData() const
{
return IndexData;
}
u32 getIndexDataCount() const
{
return IndexDataCount;
}
u32 getNodeCount() const
{
return NodeCount;
}
//! for debug purposes only, collects the bounding boxes of the tree
void getBoundingBoxes(const core::aabbox3d<f32>& box,
core::array< const core::aabbox3d<f32>* >&outBoxes) const
{
Root->getBoundingBoxes(box, outBoxes);
}
//! destructor
~Octree()
{
for (u32 i=0; i<IndexDataCount; ++i)
delete [] IndexData[i].Indices;
delete [] IndexData;
delete Root;
}
private:
// private inner class
class OctreeNode
{
public:
// constructor
OctreeNode(u32& nodeCount, u32 currentdepth,
const core::array<SMeshChunk>& allmeshdata,
core::array<SIndexChunk>* indices,
s32 minimalPolysPerNode) : IndexData(0),
Depth(currentdepth+1)
{
++nodeCount;
u32 i; // new ISO for scoping problem with different compilers
for (i=0; i!=8; ++i)
Children[i] = 0;
if (indices->empty())
{
delete indices;
return;
}
bool found = false;
// find first point for bounding box
for (i=0; i<indices->size(); ++i)
{
if (!(*indices)[i].Indices.empty())
{
Box.reset(allmeshdata[i].Vertices[(*indices)[i].Indices[0]].Pos);
found = true;
break;
}
}
if (!found)
{
delete indices;
return;
}
s32 totalPrimitives = 0;
// now lets calculate our bounding box
for (i=0; i<indices->size(); ++i)
{
totalPrimitives += (*indices)[i].Indices.size();
for (u32 j=0; j<(*indices)[i].Indices.size(); ++j)
Box.addInternalPoint(allmeshdata[i].Vertices[(*indices)[i].Indices[j]].Pos);
}
core::vector3df middle = Box.getCenter();
core::vector3df edges[8];
Box.getEdges(edges);
// calculate all children
core::aabbox3d<f32> box;
core::array<u16> keepIndices;
if (totalPrimitives > minimalPolysPerNode && !Box.isEmpty())
for (u32 ch=0; ch!=8; ++ch)
{
box.reset(middle);
box.addInternalPoint(edges[ch]);
// create indices for child
bool added = false;
core::array<SIndexChunk>* cindexChunks = new core::array<SIndexChunk>;
cindexChunks->reallocate(allmeshdata.size());
for (i=0; i<allmeshdata.size(); ++i)
{
cindexChunks->push_back(SIndexChunk());
SIndexChunk& tic = cindexChunks->getLast();
tic.MaterialId = allmeshdata[i].MaterialId;
for (u32 t=0; t<(*indices)[i].Indices.size(); t+=3)
{
if (box.isPointInside(allmeshdata[i].Vertices[(*indices)[i].Indices[t]].Pos) &&
box.isPointInside(allmeshdata[i].Vertices[(*indices)[i].Indices[t+1]].Pos) &&
box.isPointInside(allmeshdata[i].Vertices[(*indices)[i].Indices[t+2]].Pos))
{
tic.Indices.push_back((*indices)[i].Indices[t]);
tic.Indices.push_back((*indices)[i].Indices[t+1]);
tic.Indices.push_back((*indices)[i].Indices[t+2]);
added = true;
}
else
{
keepIndices.push_back((*indices)[i].Indices[t]);
keepIndices.push_back((*indices)[i].Indices[t+1]);
keepIndices.push_back((*indices)[i].Indices[t+2]);
}
}
(*indices)[i].Indices.set_used(keepIndices.size());
memcpy( (*indices)[i].Indices.pointer(), keepIndices.pointer(), keepIndices.size()*sizeof(u16));
keepIndices.set_used(0);
}
if (added)
Children[ch] = new OctreeNode(nodeCount, Depth,
allmeshdata, cindexChunks, minimalPolysPerNode);
else
delete cindexChunks;
} // end for all possible children
IndexData = indices;
}
// destructor
~OctreeNode()
{
delete IndexData;
for (u32 i=0; i<8; ++i)
delete Children[i];
}
// returns all ids of polygons partially or full enclosed
// by this bounding box.
void getPolys(const core::aabbox3d<f32>& box, SIndexData* idxdata, u32 parentTest ) const
{
#if defined (OCTREE_PARENTTEST )
// if not full inside
if ( parentTest != 2 )
{
// partially inside ?
if (!Box.intersectsWithBox(box))
return;
// fully inside ?
parentTest = Box.isFullInside(box)?2:1;
}
#else
if (Box.intersectsWithBox(box))
#endif
{
const u32 cnt = IndexData->size();
u32 i; // new ISO for scoping problem in some compilers
for (i=0; i<cnt; ++i)
{
const s32 idxcnt = (*IndexData)[i].Indices.size();
if (idxcnt)
{
memcpy(&idxdata[i].Indices[idxdata[i].CurrentSize],
&(*IndexData)[i].Indices[0], idxcnt * sizeof(s16));
idxdata[i].CurrentSize += idxcnt;
}
}
for (i=0; i!=8; ++i)
if (Children[i])
Children[i]->getPolys(box, idxdata,parentTest);
}
}
// returns all ids of polygons partially or full enclosed
// by the view frustum.
void getPolys(const scene::SViewFrustum& frustum, SIndexData* idxdata,u32 parentTest) const
{
u32 i; // new ISO for scoping problem in some compilers
// if parent is fully inside, no further check for the children is needed
#if defined (OCTREE_PARENTTEST )
if ( parentTest != 2 )
#endif
{
#if defined (OCTREE_PARENTTEST )
parentTest = 2;
#endif
for (i=0; i!=scene::SViewFrustum::VF_PLANE_COUNT; ++i)
{
core::EIntersectionRelation3D r = Box.classifyPlaneRelation(frustum.planes[i]);
if ( r == core::ISREL3D_FRONT )
return;
#if defined (OCTREE_PARENTTEST )
if ( r == core::ISREL3D_CLIPPED )
parentTest = 1; // must still check children
#endif
}
}
const u32 cnt = IndexData->size();
for (i=0; i!=cnt; ++i)
{
s32 idxcnt = (*IndexData)[i].Indices.size();
if (idxcnt)
{
memcpy(&idxdata[i].Indices[idxdata[i].CurrentSize],
&(*IndexData)[i].Indices[0], idxcnt * sizeof(s16));
idxdata[i].CurrentSize += idxcnt;
}
}
for (i=0; i!=8; ++i)
if (Children[i])
Children[i]->getPolys(frustum, idxdata,parentTest);
}
//! for debug purposes only, collects the bounding boxes of the node
void getBoundingBoxes(const core::aabbox3d<f32>& box,
core::array< const core::aabbox3d<f32>* >&outBoxes) const
{
if (Box.intersectsWithBox(box))
{
outBoxes.push_back(&Box);
for (u32 i=0; i!=8; ++i)
if (Children[i])
Children[i]->getBoundingBoxes(box, outBoxes);
}
}
private:
core::aabbox3df Box;
core::array<SIndexChunk>* IndexData;
OctreeNode* Children[8];
u32 Depth;
};
OctreeNode* Root;
SIndexData* IndexData;
u32 IndexDataCount;
u32 NodeCount;
};
} // end namespace
#endif