Chart1.AddSeries(buffer, buf_size,
		/*x0*/ from_freq_rounded, // Hz
		/*delta x*/ freq_sample_width // HZ
		);
//Chart1.SetMinXmin(from_freq_rounded);
//Chart1.SetMaxXmax(to_freq_rounded);
//Chart1.SetMinYmin(-90);
//Chart1.SetMaxYmax(0);
Chart1.SetLabels("Hz","dBFS");
Chart1.NoMark(0);
Chart1.Stroke(0,1,Blue());
Chart1.ZoomToFit(true,true,0); // X, Y, fill factor (0 = fill the whole control)
//Chart1.Refresh();

scatter.SetXYMin(10, 0).SetRange(50, 100).SetMinUnits(20, 0).SetMajorUnits(10, 20);
//scatter.ZoomToFit();

Chart1.SetXYMin(min_freq, -90).SetRange(max_freq - min_freq, 90).SetMinUnits(0,0).SetMajorUnits(1000000, 10);

Chart1.SetXYMin(min_freq, -90).SetRange(max_freq - min_freq, 90).SetMinUnits(100000,5).SetMajorUnits(1000000, 10);

// at the click of a button = in a "button event callback":
allocate global_buffer[buf_len]; // the aggregate buffer spanning all channels
zero_fill(global_buffer); // the chart starts out showing a flat line at y=0
Chart1.AddSeries(global_buffer, buf_len, starting_freq, channel_width);
Chart1.adjust_axis_units_and_view_dimensions();
Ctrl::ProcessEvents();

for (each channel)
{
	tune_into(channel);
	sample_chunk_from_channel();
	calc_FFT_for_the_channel();
	// project per channel FFT results into the overview buffer
	memcpy(global_buffer+chnl_offset, channel_FFT_output, chnl_data_len); 
	Chart1.Refresh();    // tell the ScatterCtrl to update its output
	Ctrl::ProcessEvents();  // allow the GUI to actually carry out the updates pending :-)
}