create SM from array of rates v1

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

void main() {
    // define stuff at the top to make it easier for lambda functions
    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;

    // lambda functions
    function<void(size_t)> create_sm = [&](size_t idx) { //use item_pos, item_playrate, item length, source_pos to get ruler positions of SM
        double ruler_pos = ((ts[idx] - take_start_offset)/take_playrate) + item_pos;
        double stored_ecp = GetCursorPosition();    //store cursor
        SetEditCurPos(ruler_pos, 0, 0); //move cursor to ruler-time S-pos
        // create SM(blank default, using S, S for P and no slope)
        Main_OnCommandEx(41842, 0, 0); //create SM at edit cursor
        SetEditCurPos(stored_ecp, 0, 0); //restore cursor
    };

    function<void(size_t)> modify_sm = [&](size_t idx) {
        //write to SM(idx) calculated P
        int retval = SetTakeStretchMarker(active_take, idx, tp[idx], nullptr); //sets P point, no slope yet
        // write slope to SM slope
        retval = SetTakeStretchMarkerSlope(active_take, idx, slope[idx]);  //write corrected slopes
    };

    ts ={ 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 }; // 1-based, SM S-pos table
    tr ={ 0.97, 1.0, 0.99, 0.98, 1.0, 1.03, 1.07, 1.05, 0.98 }; // 1-based, SM rate table
    size_t num_ts = ts.size(); // length of array as input above, +1 to handle 1-based table, +1 for end anchor
    // check #ts == #tp at this point?
    tro.resize(num_ts+2); //SM ro table
    slope.resize(num_ts+2); //SM slope table
    tp.resize(num_ts+2); //SM P-pos table
    tdss.resize(num_ts+2); //SM ΔSS table
    tdpp.resize(num_ts+2); //SM ΔPP table

    ts.insert(ts.begin(), 0); // make one more index to deal with 1-based arrays
    tr.insert(tr.begin(), 0);
    ts.push_back(0.0); // add one more index to hold the end anchor
    tr.push_back(0.0);

    Undo_BeginBlock(); //Hold undo block to all of proj altering code...
    MediaItem* sel_item = GetSelectedMediaItem(0, 0); //selected item
    if (( (sel_item != nullptr) & CountSelectedMediaItems(0) ) == 1) {
        // collect parameter on sel item and active take for SM decisions and S-pos to ruler-time conversion
        active_take = GetActiveTake(sel_item);  //active take in item
        total_sm = GetTakeNumStretchMarkers(active_take); //count SM in take
        item_pos = GetMediaItemInfo_Value(sel_item, "D_POSITION");  //item pos in timeline
        item_length = GetMediaItemInfo_Value(sel_item, "D_LENGTH"); //item length
        take_start_offset = GetMediaItemTakeInfo_Value(active_take, "D_STARTOFFS");  //take start offset
        take_playrate = GetMediaItemTakeInfo_Value(active_take, "D_PLAYRATE"); //take playrate(will combine with SM warping)
        if (total_sm == 0) {
            PreventUIRefresh(1); //prevent UI refresh(hold screen)
            //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
            // end-anchor
            ts[num_ts+1] = ts[num_ts]+1; //end-anchor SM S at last SM S +1sec
            tr[num_ts+1] = 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

            for (size_t i = 0; i <= num_ts+1; ++i) { //using <= instead of < for 1-based array
                modify_sm(i); //modify all SM using ts, tp, slope
            }
            PreventUIRefresh(-1); //restore UI refresh
            UpdateArrange(); //redraws the arrange window
        }
        else msg("SM already exist");   //use console msg() for debug reports, msg: already SM in take
    }
    else if (!sel_item) msg("No selected item"); //msg: no sel item
    else if (CountSelectedMediaItems(0) > 1) msg("more than 1 selected items"); //msg: more than one item sel
    Undo_EndBlock("Create SMs from array", -1); //close undo block and give annotation to undo stack.
}