Hello jmountney,
The overlay for a line can be set on a plot-by-plot basis, and you can do this either via the 3D Graph Properties window (right-click>>3D Graph Properties) or via property nodes. There are a couple things to keep in mind:
1) The overlay is assigned to a given plot index. The best way to set up indices is in the 3D Graph Properties window. The Plots tab will allow you to assign plot IDs and overlay styles for each index.
2) You'll need to build each line you want to manipulate separately as its own plot. This is done by specifying a Plot ID when using the create_plot_line function. I would recommend pre-assigning Plot IDs for the range of plots you anticipate using in the 3D Graph Properies window.
3) You can configure overlays dynamically (at runtime) via property nodes. Set the plot index you want to modify using the Active Plot property, then change the overlay parameters. Any changes you make will affect the current Active Plot.
4) The plot ID is NOT equivalent to the plot index. The plot ID is the number displayed in the 3D Graph Properties window and is the number you use when specifying a plot to add a vector to (This can be any positive or negative integer). The plot index is the index of the plot ID array. If you specify a Plot ID that's not currently in use at runtime (wire an unused number to the create_plot_line function), it will create and occupy the next available plot index. This means that unless you assign plot IDs in sequence (0,1,2,3...) the Plot IDs will not match the plot indices. Just something to keep in mind.
Hope that helps!
Tom L.
