I used geom_tile()
for plot 3 variables on the same graph... with
tile_ruined_coop<-ggplot(data=df.1[sel1,])+
geom_tile(aes(x=bonus, y=mal
scale_fill() and geom_tile() apply no statistics -or better apply stat_identity()- to your fill value=rf/300. It just computes how many colors you use and then generates the colors with the munsell function 'mnsl()'. If you want to apply some statistics only to the colors displayed you should use:
scale_colour_gradient(trans = "log")
or
scale_colour_gradient(trans = "sqrt")
Changing the colors among the tiles could not be the best idea since the plots have to be comparable, and you compare the values by their colours. Hope this helps