source: GTP/trunk/App/Demos/Vis/FriendlyCulling/src/BvhLoader.cpp @ 3269

#include "BvhLoader.h"
#include "BvhConstructor.h"
#include "gzstream.h"

#include <queue>
#include <stack>
#include <fstream>
#include <iostream>



#ifdef _CRT_SET
        #define _CRTDBG_MAP_ALLOC
        #include <stdlib.h>
        #include <crtdbg.h>

        // redefine new operator
        #define DEBUG_NEW new(_NORMAL_BLOCK, __FILE__, __LINE__)
        #define new DEBUG_NEW
#endif


namespace CHCDemoEngine
{

using namespace std;


#define TYPE_INTERIOR -2
#define TYPE_LEAF -3



BvhNode *BvhFactory::LoadNextNode(igzstream &stream, BvhInterior *parent)
{
        int nodeType;
        stream.read(reinterpret_cast<char *>(&nodeType), sizeof(int));

        BvhNode *node;

        if (nodeType == TYPE_LEAF)
                node = new BvhLeaf(parent);
        else if (nodeType == TYPE_INTERIOR)
                node = new BvhInterior(parent);
        else
                cerr << "error: wrong node type: " << nodeType << endl;
                

        Vector3 bMin, bMax;

        stream.read(reinterpret_cast<char *>(&(node->mFirst)), sizeof(int));
        stream.read(reinterpret_cast<char *>(&(node->mLast)), sizeof(int));

        stream.read(reinterpret_cast<char *>(&bMin), sizeof(Vector3));
        stream.read(reinterpret_cast<char *>(&bMax), sizeof(Vector3));

        node->mBox = AxisAlignedBox3(bMin, bMax);
        node->mArea = node->mBox.SurfaceArea();

        //cout << "box: " << node->mBox << " area: " << node->mArea << endl;
        
        return node;
}


Bvh *BvhFactory::Create(const string &filename, 
                                                const SceneEntityContainer &staticEntities,
                                                const SceneEntityContainer &dynamicEntities,
                                                int maxDepthForTestingChildren)

{
        queue<BvhNode *> tQueue;
        igzstream stream(filename.c_str());

        if (!stream.is_open()) return NULL;

        cout << "\n*******************\nloading bvh from file " << filename << " ..." << endl;

        Bvh *bvh = new Bvh(staticEntities, dynamicEntities, maxDepthForTestingChildren);

        BvhNode *root = LoadNextNode(stream, NULL);

        bvh->mStaticRoot = root;
        // we have at least the root, the static and the dynamic branch
        bvh->mNumNodes = 3;

        cout << "static bvh bb: " << root->mBox << endl;

        tQueue.push(root);
        
        while (!tQueue.empty())
        {
                BvhNode *node = tQueue.front();
                tQueue.pop();

                if (!node->IsLeaf())
                {
                        bvh->mNumNodes += 2;

                        BvhInterior *interior = static_cast<BvhInterior *>(node);

                        BvhNode *front = LoadNextNode(stream, interior);
                        BvhNode *back = LoadNextNode(stream, interior);

                        interior->mFront = front;
                        interior->mBack = back;

                        front->mDepth = interior->mDepth + 1;
                        back->mDepth = interior->mDepth + 1;

                        tQueue.push(front);                     
                        tQueue.push(back);
                }
        }

        cout << "... finished loading " << bvh->mNumNodes - 2 << " static bvh nodes" << endl;


        ///////////
        //-- create dynamic part of the hierarchy

        bvh->CreateDynamicBranch();

        ///////////
        //-- post process nodes

        bvh->PostProcess();

        cout << "bvh bb: " << bvh->mBox << endl;

        return bvh;
}


Bvh *BvhFactory::Create(const SceneEntityContainer &staticEntities,
                                                const SceneEntityContainer &dynamicEntities,
                                                int maxDepthForTestingChildren)
{

        Bvh *bvh = new Bvh(staticEntities, dynamicEntities, maxDepthForTestingChildren);

        BvhConstructor bvhConstructor(bvh->mGeometry, 
                                          0,
                                                                  (int)bvh->mStaticGeometrySize - 1);

        int numNodes;
        bvh->mStaticRoot = bvhConstructor.Construct(numNodes);

        bvh->mNumNodes = 2 + numNodes;

        cout << "created " << bvh->mNumNodes - 2 << " static bvh nodes" << endl;


        ///////////
        //-- create dynamic part of the hierarchy

        bvh->CreateDynamicBranch();


        ///////////
        //-- post process nodes

        bvh->PostProcess();

        cout << "bvh bb: " << bvh->mBox << endl;

        return bvh;
}


}