Stacked Bar Chart Opacity of Some Colors

[Sethmr]

I had charts previously that had stacked bars with different alpha components like so:

set1.barSpace = 1000
set1.setColor(UIColor.lightBlueColor().colorWithAlphaComponent(0.8))

set2.barSpace = 1000
set2.setColor(UIColor.greenColor().colorWithAlphaComponent(0.8))

set3.barSpace = 1000
set3.setColor(UIColor.orangeColor().colorWithAlphaComponent(0.3))

data.groupSpace = 1300

I know this was a hacky method of stacking the bars but it worked. Now I want to do this again so that the bars that overlap blend into each other with their colors in Swift 3. Is there an option to do this? It seems like only the visible parts of the bars are drawn now. I don't want to overlap 3 charts because that seems really messy. If that is my only choice let me know. I switched from 3 sets to a single set. Maybe I should go back to 3 sets now that I am getting the hang of the new framework.