Method paint_prepare

DSView/pv/view/dsosignal.cpp:648–689

}

void DsoSignal::paint_prepare()
{
    assert(_view);

    if (_data->empty() || !_data->has_data(get_index()))
        return; 

    if (session->trigd()) {
        if (get_index() == session->trigd_ch()) {
            uint8_t slope = DSO_TRIGGER_RISING;
            int v;
            bool ret;

            ret = session->get_device()->get_config_byte(SR_CONF_TRIGGER_SLOPE, v);
            if (ret) {
                slope = (uint8_t)v;
            }

            int64_t trig_index = _view->get_trig_cursor()->index();
            if (trig_index >= (int64_t)_data->get_sample_count())
                return;

            const uint8_t *const trig_samples = _data->get_samples(0, 0, get_index());
            for (uint16_t i = 0; i < TrigHRng; i++) {
                const int64_t i0 = trig_index - i - 1;
                const int64_t i1 = trig_index - i;
                if (i1 < 0)
                    break;
                const uint8_t t0 = trig_samples[i0];
                const uint8_t t1 = trig_samples[i1];
                if((slope == DSO_TRIGGER_RISING && t0 >= _trig_value && t1 <= _trig_value) ||
                   (slope == DSO_TRIGGER_FALLING && t0 <= _trig_value && t1 >= _trig_value)) {
                    const double xoff = (t1 == t0) ? 0 : (_trig_value - t0) * 1.0 / (t1 - t0);
                    _view->set_trig_hoff(i + 1 - xoff);
                    break;
                }
            }
        }
    } else {
        _view->set_trig_hoff(0);
    }
}

void DsoSignal::paint_back(QPainter &p, int left, int right, QColor fore, QColor back)
{