famitracker_cleanup_duplicate_patterns

    for (unsigned int i = 0; i <= m_iTracks; ++i)
    for (unsigned int c = 0; c < m_iChannelsAvailable; ++c)
    {
        TRACE2("Trim: %d, %d\n", i, c);

        unsigned int uiPatternUsed[MAX_PATTERN];

        // mark all as unused
        for (unsigned int ui=0; ui < MAX_PATTERN; ++ui)
        {
            uiPatternUsed[ui] = MAX_PATTERN;
        }

        // map used patterns to themselves
        for (unsigned int f=0; f < m_pTunes[i]->GetFrameCount(); ++f)
        {
            unsigned int uiPattern = m_pTunes[i]->GetFramePattern(f,c);
            uiPatternUsed[uiPattern] = uiPattern;
        }

        // remap duplicates
        for (unsigned int ui=0; ui < MAX_PATTERN; ++ui)
        {
            if (uiPatternUsed[ui] == MAX_PATTERN) continue;
            for (unsigned int uj=0; uj < ui; ++uj)
            {
                unsigned int uiLen = m_pTunes[i]->GetPatternLength();
                bool bSame = true;
                for (unsigned int uk = 0; uk < uiLen; ++uk)
                {
                    stChanNote* a = m_pTunes[i]->GetPatternData(c, ui, uk);
                    stChanNote* b = m_pTunes[i]->GetPatternData(c, uj, uk);
                    if (0 != ::memcmp(a, b, sizeof(stChanNote)))
                    {
                        bSame = false;
                        break;
                    }
                }
                if (bSame)
                {
                    uiPatternUsed[ui] = uj;
                    TRACE2("Duplicate: %d = %d\n", ui, uj);
                    break;
                }
            }
        }

        // apply mapping
        for (unsigned int f=0; f < m_pTunes[i]->GetFrameCount(); ++f)
        {
            unsigned int uiPattern = m_pTunes[i]->GetFramePattern(f,c);
            m_pTunes[i]->SetFramePattern(f,c,uiPatternUsed[uiPattern]);
        }
    }