create SM from array of rates v2

void msg(string m) { //debug console
    ShowConsoleMsg(m.c_str()); //string
    ShowConsoleMsg("\n"); //newline
}

void main() {
    vector<double> ts, tr, tro, slope, tp, tdss, tdpp;
    MediaItem_Take* active_take;
    int total_sm;
    double take_start_offset, take_playrate, item_pos, item_length;

    auto create_sm = [&](size_t idx) {
        double ruler_pos = ((ts[idx] - take_start_offset)/take_playrate) + item_pos;
        double stored_ecp = GetCursorPosition();
        SetEditCurPos(ruler_pos, 0, 0);

        Main_OnCommandEx(41842, 0, 0);
        SetEditCurPos(stored_ecp, 0, 0);
    };

    ts ={ 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 };
    tr ={ 0.97, 1.0, 0.99, 0.98, 1.0, 1.03, 1.07, 1.05, 0.98 };

    size_t num_ts = ts.size();

    tro.resize(num_ts+2);
    slope.resize(num_ts+2);
    tp.resize(num_ts+2);
    tdss.resize(num_ts+2);
    tdpp.resize(num_ts+2);

    ts.insert(ts.begin(), 0.0);
    tr.insert(tr.begin(), 0.0);

    Undo_BeginBlock();

    MediaItem* sel_item = GetSelectedMediaItem(0, 0);

    if (sel_item == nullptr) { msg("No selected item"); return; }

    active_take = GetActiveTake(sel_item);

    if (GetTakeNumStretchMarkers(active_take)) { msg("SM already exist"); return; }

    item_pos = GetMediaItemInfo_Value(sel_item, "D_POSITION");
    item_length = GetMediaItemInfo_Value(sel_item, "D_LENGTH");
    take_start_offset = GetMediaItemTakeInfo_Value(active_take, "D_STARTOFFS");
    take_playrate = GetMediaItemTakeInfo_Value(active_take, "D_PLAYRATE");

    //zero-anchor
    if (ts[1] <= 0) ts[0] = ts[1]-1; //zero-anchor SM to left of SM1
    else ts[0] = 0; // zero-anchor SM at 0 (source)
    tro[0] = tr[1]; //zero-anchor SM ro same rate as rate1(no slope)
    slope[0] = 0;   //zero-anchor SM flat slope
    tp[0] = ts[0];  //zero-anchor SM P same as its S
    tdss[0] = ts[1]-ts[0]; //zero-anchor SM ΔSS(next S - this S)
    tdpp[0] = tdss[0]/tro[0]; //zero-anchor SM ΔPP = ΔSS/ro

    PreventUIRefresh(1); //prevent UI refresh(hold screen)

    // end-anchor
    ts.push_back(ts[num_ts]+1); //end-anchor SM S at last SM S +1sec
    tr.push_back(tr[num_ts]); //end-anchor SM tr at last SM rate(for array)
    //tro[num_ts+1] = tr[num_ts] //end-anchor SM ro at last SM rate
    slope[num_ts+1] = 0; //end-anchor SM flat slope
    create_sm(0); //create zero-anchor SM using ts, ts as tp, no slope

    for (size_t i = 1; i <= num_ts; ++i) { //loop through table positions and rates, using <= instead of < for 1-based array
        tro[i] = (tr[i]+tr[i+1])/2; //overall rate = mean of r1 and r2 rates for marker
        slope[i] = 1-((2*tr[i])/(tr[i]+tr[i+1])); //slope = function of r1 and r2
        tp[i] = tp[i-1]+tdpp[i-1]; // this P = last P + last ΔPP
        tdss[i] = ts[i+1]-ts[i]; // this ΔSS = next S - this S
        tdpp[i] = tdss[i]/tro[i]; // this ΔPP = ΔSS/ro
        create_sm(i); //create SM using ts, ts as tp, no slope
    }

    tp[num_ts+1] = tp[num_ts]+tdpp[num_ts]; //end-anchor SM P = last P + last ΔPP
    create_sm(num_ts+1); //create end-anchor SM using ts, ts as tp, no slope

    //modify all SM using ts, tp, slope
    for (size_t i = 0; i <= num_ts+1; ++i) {
        SetTakeStretchMarker(active_take, i, tp[i], nullptr);
        SetTakeStretchMarkerSlope(active_take, i, slope[i]);
    }

    PreventUIRefresh(-1); //restore UI refresh
    UpdateArrange(); //redraws the arrange window
    Undo_EndBlock("Create SMs from array", -1); //close undo block and give annotation to undo stack.
}