The graphs and charts plot array-type data (e.g an array of waveforms, an array of xy-plot points, an array of clusters of x-point arrays and y-point arrays, etc), from front-to-back such that when data-points from multiple different elements of that array (multipe datasets) need to be drawn at the same location, data points contained within the first dataset will appear in front of the second , the second in front of the third etc.
Therefore, to plot your background data in the same indicator as the comparison data, you'll want to plot your background waveform at a plot index greater than the number of comparison sets you want to see. You can use thicker lines and bigger point styles on the background waveform to ensure that it will be visible even if you
r data matches exactly.
You won't be able to put the background waveform at plot index 1 without building at least a two element waveform array plotting something at plot zero(plot indices are zero-indexed {0,1,2,...}. If you want to be able to plot the background data to its background index before your foreground data is ready, plotting an empty element containing at least one NaN point can help you skip over a waveform index. The alternative is to build the array by including some dummy data and setting the visibility property of the dummy plots to zero.
You may find the ability to temporarily turn off front-panel refresh/redraw while graphs are being updated useful to avoid seeing the nasty details.
