Valve BSP & Bullet Physics

//Map converter part
logger.logDebug("Scanning tree...");
std::vector<int> leafIds;
exploreTree(nodes, models[0].node, leafIds); //Model 0 is the "world" model, without entities
logger.logDebug("Found %i leaves", leafIds.size());

std::vector<unsigned short> okBrushes;
unsigned int oldPos = bb.getCursorPos();
unsigned int pObjs = 0;
bb << pObjs;

for(int i = 0; i < leafIds.size(); i++) {
    int lbCnt = leafs[leafIds[i]].leafBrushCnt;

    for(int j = 0; j < lbCnt; j++) {
        int lbId = leafs[leafIds[i]].leafBrushId + j;
        unsigned short bId = lbrushes[lbId];
        Brush br = brushes[bId];

        if((br.contents & BRUSH_FLAG_SOLID) > 0 && br.sideCount > 0) { //BRUSH_FLAG_SOLID = 1
            bool hasBeenDone = false;
            for(int k = 0; k < okBrushes.size(); k++) {
                if(okBrushes[k] == bId) {
                    hasBeenDone = true;
                    break;
                }
            }

            if(hasBeenDone)
                continue;

            bb << (unsigned short) br.sideCount;
            pObjs++;

            for(int k = 0; k < br.sideCount; k++) {
                Plane pl = planes[bsides[br.sideStart + k].planeId];

                bb << pl.normal;
                bb << (float) -pl.distance;
            }

            okBrushes.push_back(bId);
        }
    }
}

bb.setCursorPos(oldPos, ByteBuffer::CR_Begin);
bb << pObjs;
bb.setCursorPos(0, ByteBuffer::CR_End);

logger.logDebug("Leaves OK; found %i solid brushes!", (int) pObjs);

//Map loader part
reader.readData<unsigned int>(&poCnt);

for(int i = 0; i < poCnt; i++) {
    btAlignedObjectArray<btVector3> poNormals;
    unsigned short nrmCnt;
    reader.readData<unsigned short>(&nrmCnt);

    for(int j = 0; j < nrmCnt; j++) {
        float nx, ny, nz, nw;
        reader.readData<float>(&nx);
        reader.readData<float>(&ny);
        reader.readData<float>(&nz);
        reader.readData<float>(&nw);

        btVector3 nrm;
        nrm.setValue(nx, ny, nz);
        nrm[3] = nw;
        poNormals.push_back(nrm);
    }

    btAlignedObjectArray<btVector3> poVertices;
    btGeometryUtil::getVerticesFromPlaneEquations(poNormals, poVertices);

    for(int j = 0; j < poVertices.size(); j++) {
        poVertices[j] *= LEVEL_SCALE; //LEVEL_SCALE is .25f; for rendering I scale the matrix using the same value

        //swap
        float vz = poVertices[j].z();
        poVertices[j].setZ(-poVertices[j].y());
        poVertices[j].setY(vz);
    }

    btConvexHullShape *shape = new btConvexHullShape(&poVertices[0].x(), poVertices.size());
    btRigidBody *body = new btRigidBody(.0f, new btDefaultMotionState, shape);

    m_shapes.push_back(shape);
    m_bodies.push_back(body);
}