extern "C" void Membrane_D3Q19_Unpack(int q, int *list, int *links, int start, int linkCount,
                                    double *recvbuf, double *dist, int N) {
    //....................................................................................
    // Unack distribution from the recv buffer
    // Distribution q matche Cqx, Cqy, Cqz
    // swap rule means that the distributions in recvbuf are OPPOSITE of q
    // dist may be even or odd distributions stored by stream layout
    //....................................................................................
    int n, idx, link;
    for (link=0; link<linkCount; link++){

    	idx = links[start+link];
        // Get the value from the list -- note that n is the index is from the send (non-local) process
        n = list[start + idx];
        // unpack the distribution to the proper location
        if (!(n < 0))
            dist[q * N + n] = recvbuf[start + idx];
    }
}

extern "C" void Membrane_D3Q19_Transport(int q, int *list, int *links, double *coef, int start, int offset, 
		int linkCount, double *recvbuf, double *dist, int N){
    //....................................................................................
    // Unack distribution from the recv buffer
    // Distribution q matche Cqx, Cqy, Cqz
    // swap rule means that the distributions in recvbuf are OPPOSITE of q
    // dist may be even or odd distributions stored by stream layout
    //....................................................................................
    int n, idx, link;
    double alpha;
    for (link=offset; link<linkCount; link++){

    	idx = list[start+link];
        // Get the value from the list -- note that n is the index is from the send (non-local) process
        n = list[start + idx];
        alpha = coef[start + idx];
        // unpack the distribution to the proper location
        if (!(n < 0))
            dist[q * N + n] = alpha*recvbuf[start + idx];
    }
}