protected void Init(UltimateTerrain uTerrain)
    {
        converter = uTerrain.Converter;
        Vector3d min, max;

        min.x = corner.x;
        max.x = min.x;
        if (vL.x < 0)
        {
            min.x += vL.x;
        }
        else
        {
            max.x += vL.x;
        }
        if (vH.x < 0)
        {
            min.x += vH.x;
        }
        else
        {
            max.x += vH.x;
        }
        if (vW.x < 0)
        {
            min.x += vW.x;
        }
        else
        {
            max.x += vW.x;
        }

        min.y = corner.y;
        max.y = min.y;
        if (vL.y < 0)
        {
            min.y += vL.y;
        }
        else
        {
            max.y += vL.y;
        }
        if (vH.y < 0)
        {
            min.y += vH.y;
        }
        else
        {
            max.y += vH.y;
        }
        if (vW.y < 0)
        {
            min.y += vW.y;
        }
        else
        {
            max.y += vW.y;
        }

        min.z = corner.z;
        max.z = min.z;
        if (vL.z < 0)
        {
            min.z += vL.z;
        }
        else
        {
            max.z += vL.z;
        }
        if (vH.z < 0)
        {
            min.z += vH.z;
        }
        else
        {
            max.z += vH.z;
        }
        if (vW.z < 0)
        {
            min.z += vW.z;
        }
        else
        {
            max.z += vW.z;
        }

        from = new Vector3i(min) - Vector3i.one;
        to   = new Vector3i(max) + Vector3i.one;

        oppositeCorner = corner + vL + vH + vW;
        nLH            = Vector3d.Cross(vL, vH).Normalized;
        nLH           *= Math.Sign(UMath.DistanceToPlane(oppositeCorner, corner, nLH));
        nHW            = Vector3d.Cross(vH, vW).Normalized;
        nHW           *= Math.Sign(UMath.DistanceToPlane(oppositeCorner, corner, nHW));
        nWL            = Vector3d.Cross(vW, vL).Normalized;
        nWL           *= Math.Sign(UMath.DistanceToPlane(oppositeCorner, corner, nWL));

        halfExtents = new Vector3d(vW.Magnitude, vH.Magnitude, vL.Magnitude) * 0.5;
    }