drawing multiple lines on intensity graph

[RavensFan]

You are missing the value change events for your angle2, spacing2, etc. controls.  Your event only handles the value change for the first group of controls.

[hey_yo]

wow~ I didn't notice that.

sorry for asking stupid question~

thank you!

[hey_yo]

sorry for annoying continuously questioning......

but I found some problem when I apply into my example

when I zoom in a specified area, I found that the lines won't change with the magnification.

I try to set absolute coordinate (in draw line.vi) a constant true, but it seems that it's not that problem~

sorry I am not familiar with these, any suggestion?

[altenbach]

The lines are in pixel coordinates, not in the native coordinates of the plot. You would need to create an event for "scale range change" of the graph and recalculate and redraw the lines accordingly. If the offset and multiplier of your axes are not at the default, you need to take that into account too.