void setGeomData(scene::IMesh* mesh, scene::ISceneNode *node, dGeomID &geom)
{
    if(mesh==NULL) return; // do nothing if the mesh or node is NULL
    int i,j,ci,cif,cv;
    int indexcount=0;
    int vertexcount=0;
    // count vertices and indices
    for(i=0;i<mesh->getMeshBufferCount();i++){
        irr::scene::IMeshBuffer* mb=mesh->getMeshBuffer(i);
        indexcount+=mb->getIndexCount();
        vertexcount+=mb->getVertexCount();
    }
    // build structure for ode trimesh geom
    dVector3 *vertices=new dVector3[vertexcount];
    int *indices=new int[indexcount];
    // fill trimesh geom
    ci=0;
    cif=0;
    cv=0;
    for(i=0;i<mesh->getMeshBufferCount();i++){
        irr::scene::IMeshBuffer* mb=mesh->getMeshBuffer(i);
        // fill indices
        irr::u16* mb_indices=mb->getIndices();
        for(j=0;j<mb->getIndexCount();j++){
            indices[ci]=cif+mb_indices[j];
            ci++;
        }
        cif=cif+mb->getVertexCount();
        // fill vertices
        if(mb->getVertexType()==irr::video::EVT_STANDARD){
            irr::video::S3DVertex* mb_vertices=(irr::video::S3DVertex*)mb->getVertices();
            for(j=0;j<mb->getVertexCount();j++){
                vertices[cv][0]=mb_vertices[j].Pos.X;
                vertices[cv][1]=mb_vertices[j].Pos.Y;
                vertices[cv][2]=mb_vertices[j].Pos.Z;
                cv++;
            }
        }else if(mb->getVertexType()==irr::video::EVT_2TCOORDS){
            irr::video::S3DVertex2TCoords* mb_vertices=(irr::video::S3DVertex2TCoords*)mb->getVertices();
            for(j=0;j<mb->getVertexCount();j++){
                vertices[cv][0]=mb_vertices[j].Pos.X;
                vertices[cv][1]=mb_vertices[j].Pos.Y;
                vertices[cv][2]=mb_vertices[j].Pos.Z;
                cv++;
            }
        }
    }
    irr::core::vector3df pos=node->getPosition();
    // build the trimesh data
    dTriMeshDataID data=dGeomTriMeshDataCreate();
    dGeomTriMeshDataBuildSimple(data,(dReal*)vertices,vertexcount,indices,indexcount);
    // build the trimesh geom
    geom=dCreateTriMesh(space,data,0,0,0);
    // set the geom position
    dGeomSetPosition(geom,pos.X,pos.Y,pos.Z);

}