// copy starting point
    double ax = accx;
    double ay = accy;

        _find_next_intercept(&accx, &accy, slope);
        curx = static_cast<int>(accx);
        cury = static_cast<int>(accy);

        _find_next_intercept(&ax, &ay, slope);
        curx = static_cast<int>(ax);
        cury = static_cast<int>(ay);