Function index_collapse

cmp_compressonatorlib/bc7/reconstruct.cpp:151–188

}

void index_collapse  // assymtric of x->n-x, but this does not matter below
    (int index[], int numEntries)
{
#ifdef USE_DBGTRACE
    DbgTrace(());
#endif
    int k;
    int d, D;

    int mi;
    int Mi;

    if (numEntries == 0)
        return;

    mi = Mi = index[0];

    for (k = 0; k < numEntries; k++)
    {
        mi = mi < index[k] ? mi : index[k];
        Mi = Mi > index[k] ? Mi : index[k];
    }

    D = 1;

    for (d = 2; d <= Mi; d++)
    {
        for (k = 0; k < numEntries; k++)
            if ((index[k] - mi) % d != 0)
                break;

        if (k >= numEntries)
            D = d;
    }

    for (k = 0; k < numEntries; k++)
        index[k] = (index[k] - mi) / D;
}

void index_expand  // assymtric of x->n-x, but this does not matter below
    (int index[], int numEntries, int max_clusters)