How to use both fill colour and texture in figure legend?

Question

I am creating 2 overlapping histograms on a single plot. The diagram needs to be clear in black and white, so I am using a combination of colours and textures to help distinguish between the histograms.

The problem is with the legend, where I can either get the colours to show up, or the textures, but not both. This code produces a legend with empty boxes:

dat <- rnorm(100)
dat2<-rnorm(100,1)

hist(dat, col = "grey", xlim = c(-3, 5), ylim = c(0,35))
hist(dat2, density = 20, add = TRUE)
legend("topright", legend = c(1,2), fill = c("grey", NA), density = c(0, 20))

I don't have the reputation to post images, but a link to the output is below: https://drive.google.com/uc?id=0B4VH8cX4Cf7bNjhVQnUwWWVaMEk

I can get the colour alone to display correctly:

hist(dat, col = "grey", xlim = c(-3, 5), ylim = c(0,35))
hist(dat2, density = 20, add = TRUE)
legend("topright", legend = c(1,2), fill = c("grey", NA))

https://drive.google.com/uc?id=0B4VH8cX4Cf7bcXJvakZxN0x5c1U

And the textures alone also works:

hist(dat, col = "grey", xlim = c(-3, 5), ylim = c(0,35))
hist(dat2, density = 20, add = TRUE)
legend("topright", legend = c(1,2), density = c(0, 20))

(I've can only post 2 links, also because I don't have enough reputation)

It just won't work together. What am I doing wrong?

Thanks!

Answer 1

Figured it out. The fill argument in legend() also applies to the shading lines, so when I specified that fill for the second legend item was NA, it meant the shading lines were invisible.

The following code produces the result I want:

hist(dat, col = "grey", xlim = c(-3, 5), ylim = c(0,35))
hist(dat2, density = 20, add = TRUE)
legend("topright", legend = c(1,2), fill = c("grey", "black"), density = c(1000, 20))