I am using R maftools' oncoplot function to summarize the MAF file for a particular cohort of data. Currently on the top bar of the oncoplot, I am plotting an outcome of interest.

Per documentation, I am passing a dataframe to the topBarData argument and it handles the display of the bar plot, giving some minor flexibility via other arguments.

However what I would like to do is color this outcome barplot by the categorical data of another outcome (I know I can do this on the bottom via annotations but would rather have this codified in the top bar plot), and additionally I would like to draw a horizontal line at some cutoff value).

Is there any way to do this? Ideally maftools would allow passing a ggplot object here for maximum flexibility. If maftools cannot do this, is there another tool that's perhaps more flexible e.g. ComplexHeatmap or GenVisR? I know I could also possibly do this all from scratch via ggplot but this would be a massive effort for a single figure, and maftools is wonderfully handling 90% of what I want to do with this image.

Thanks!