Method drawGraph

firmware/src/app.cpp:102–232

y coordinates including bottom,top are from physical bottom of the screen

    const int y_from_bottom = bottom + t_pixels;
    return disph - y_from_bottom;
}

// y coordinates including bottom,top are from physical bottom of the screen
void App::drawGraph(int left, int right, int bottom, int top, const int16_t* dataY, int dataCount, int16_t* min, int16_t* max, bool forceRange, int16_t forcedMin, int16_t forcedMax)
{
    auto d = disp->d;
    uint32_t timeStamp = micros();
    

    if (left >= right || bottom >= top) 
        return;

    const int width  = right - left;
    const int height = top - bottom;

    // convert graph box to screen coordinates once
    const int invt = disph - top;
    const int invb = disph - bottom;

    // outline
    d->drawLine(left,  invt,  right, invt,  black);
    d->drawLine(left,  invb,  right, invb,  black);
    d->drawLine(left,  invt,  left,  invb,  black);
    d->drawLine(right, invt,  right, invb, black);
    
    // grid
    for (int i = 1; i < width - 1; i++)
    {
        uint16_t col = i % 2 ? black : white;
        d->drawPixel(left + i, invt+(height / 2), col);
        d->drawPixel(left + i, invt+(height / 4), col);
        d->drawPixel(left + i, invb-(height / 4), col);
    }
    for (int i = 1; i < height - 1; i++)
    {
        uint16_t col = i % 2 ? black : white;
        d->drawPixel(left + width/2, invt + i, col);
        d->drawPixel(left + width/4, invt + i, col);
        d->drawPixel(right - width/4, invt + i, col); 
    }

    if (!dataY || dataCount < 2) 
        return;

    // min/max
    int ymin = dataY[0], ymax = dataY[0];
    for (int i = 1; i < dataCount; ++i) {
        const int v = dataY[i];
        if (v < ymin) ymin = v;
        if (v > ymax) ymax = v;
    }
    *max = ymax;
    *min = ymin;

    if (forceRange) {
        ymin = forcedMin;
        ymax = forcedMax;
    }