I have a tibble with the following structure:
library(tidyverse)
dmd <- tibble(sample = rep(c(1,2,3), each = 2),
time = rep(c(1,2),3),
score = c(0.69,0.95,1,0.90,1,0.76)) %>%
mutate(x = map(base::strsplit(paste(sample,
sample + 0.5,
sample,
sample - 0.5,
sep = ","),
split = ","),
as.numeric)) %>%
mutate(y = map(base::strsplit(paste(time + 0.5,
time,
time - 0.5,
time,
sep = ","),
split = ","),
as.numeric)) %>%
unnest(c(x,y)) %>%
group_by(sample,time) %>%
mutate(group_id = cur_group_id()) %>%
ungroup
# A tibble: 24 × 6
sample time score x y group_id
<dbl> <dbl> <dbl> <dbl> <dbl> <int>
1 1 1 0.69 1 1.5 1
2 1 1 0.69 1.5 1 1
3 1 1 0.69 1 0.5 1
4 1 1 0.69 0.5 1 1
5 1 2 0.95 1 2.5 2
6 1 2 0.95 1.5 2 2
7 1 2 0.95 1 1.5 2
8 1 2 0.95 0.5 2 2
9 2 1 1 2 1.5 3
10 2 1 1 2.5 1 3
# … with 14 more rows
I then use grDevices::rgb to generate a grayscale hex value dcolor based on score. The if() statement doesn’t do much in this example, but it’s important that I retain this element for the functionalization of my code.
minsc <- min(dmd$score)
thrsh <- 0.75
if (minsc < thrsh) {
floor <- minsc
} else {
floor <- thrsh
}
dmd <- dmd %>% mutate(temp = (1 - score) / (1 - floor)) %>%
mutate(dcolor = grDevices::rgb(temp,temp,temp)) %>%
dplyr::select(-temp)
# A tibble: 24 × 7
sample time score x y group_id dcolor
<dbl> <dbl> <dbl> <dbl> <dbl> <int> <chr>
1 1 1 0.69 1 1.5 1 #FFFFFF
2 1 1 0.69 1.5 1 1 #FFFFFF
3 1 1 0.69 1 0.5 1 #FFFFFF
4 1 1 0.69 0.5 1 1 #FFFFFF
5 1 2 0.95 1 2.5 2 #292929
6 1 2 0.95 1.5 2 2 #292929
7 1 2 0.95 1 1.5 2 #292929
8 1 2 0.95 0.5 2 2 #292929
9 2 1 1 2 1.5 3 #000000
10 2 1 1 2.5 1 3 #000000
# … with 14 more rows
If I plot dmd with geom_polygon, dcolor is interpreted as a factor.
ggplot(dmd) +
geom_polygon(mapping = aes(x = x,
y = y,
group = group_id,
fill = dcolor),
color = "black") +
theme_void()
I would like to force ggplot to use the hex values given in dcolor as the fill color for each diamond. Using scale_fill_manual gets me closer, but the colors are still incorrect (#000000 should be black, #FFFFFF should be white).
pal <- dmd %>% dplyr::select(group_id, dcolor) %>%
unique %>% dplyr::select(dcolor) %>% as_vector
ggplot(dmd) +
geom_polygon(mapping = aes(x = x,
y = y,
group = group_id,
fill = dcolor),
color = "black") +
scale_fill_manual(values = palette(pal)) +
theme_void()
>Solution :
You could achieve your desired result using scale_fill_identity:
library(tidyverse)
ggplot(dmd) +
geom_polygon(mapping = aes(x = x,
y = y,
group = group_id,
fill = dcolor),
color = "black") +
theme_void() +
scale_fill_identity(guide = guide_legend())
