Add non-smoothed "step" method aka stacked bar chart

[georgeblck]

Hello,

thank you for this package and its beautiful plots. Up until recently I have been using the outdated htmlwidgets package streamgraph because it just looks good. They have an option that basically renders a stacked bar chart - which obviously can be achieved outside of a streamgraph package - but I really like the flexibility of being able to switch to a non-smoothed graph that still offers the streamgraphs-controls e.g. type and sorting in ggstream. Not only for the aesthetic but also for seeing the data as-is without distortion.

Would it be possible to add this to your package?

[anneebarkley]

Hello! Love ggstream, but I too would find a step-wise stream plot incredibly helpful. I'm in the paleo world, and samples from our sediment cores and not taken at regular time intervals. I would love to use ggstream, but the smoothing isn't capturing the abrupt changes in sources, which is some of the coolest parts of my data! (Compare between first and second vertical dashed lines). The grey lines behind the streamplot are when the samples were taken.

I have tried decreasing the smoothing (bw = < than the default of 0.75), but the results become non-sensical.

Thanks for considering this suggestion! Anne