Adding multiple shadows/rectangles to ggplot2 graph

Question

I am trying to add multiple shadows/rectangles over a ggplot2 graph. In this reproducible example, I am only adding 3, but I may need to add up to a hundred using the full

Answer 1

it's better to use only one layer, with suitable mapping,

tempindex <- transform(tempindex, 
                       id = 1:3,
                       tier = c(1,1,2))


ggplot(temp, aes(Season,value, color=group)) + 
  geom_rect(data=tempindex, inherit.aes=FALSE,
            aes(xmin=xmin,xmax=xmax,ymin=ymin,ymax=ymax,
                group=id, fill = factor(tier)), alpha=0.2)+
  geom_point(size=4, shape=19) +
  scale_color_manual(values=c("red", "gray55"))+
  scale_fill_manual(values=c("green", "blue")) +
  guides(fill="none")