Is there a simple/elegant way to do bar graphs in RRDTool?

[Peter_V]

I found a way online to create bar graphs, but it's clunky. It takes 6 to 8 RRD graph commands per bar so if I plot three bars per day for a week period, I end up with 150+ commands.
I simplified the script a bit by using a for loop in perl to create an array with the statements and then just pass the array to RRD graph, but it's still kind of clunky and slow.

Is this something that Cacti can do for me? I'm still trying to figure out what the advantage is from using cacti, not that I have enough room on my server to install it right now anyway.

FWIW here is a sample

Yellow is solar production, green is household consumption and blue is Net pushed to grid. I'm still working on it, but when I get finished I'll probably use red to indicate any Net pulled from the grid.