Is there any way to control the appearance of nodes and labels?

[coderodent-calfee]

I found this: https://stackoverflow.com/questions/20406346/how-to-plot-tree-graph-web-data-on-gnuplot
however the solutions there seem to be in a script form, and not controlled by the code. Is there a path to pass the required data to the backend to get the desired result?

[coderodent-calfee]

g->node_labels({ "foo" }); an array of node labels gets my text onto the screen, still unsure about controlling the circle fill or the offsets of the labels.