Experimenting with geom_spoke in ggplot2

geom_spoke_fun.R

library(tidyverse)

base_grid <- tibble(
  x = c(1:20),
  y = c(1:20)
) %>% expand.grid

my_grid <- base_grid %>%
  mutate(color=sample(c("#CFF09E","#A8DBA8","#79BD9A","#3B8686","#0B486B"), 
                      replace=T, size=nrow(my_grid)),
         angle = sample(seq(pi/4,2*pi,by=pi/2),
                        replace=T, size=nrow(my_grid)))  %>%
  mutate(xend=x+sqrt(2)*cos(angle),
         yend=y+sqrt(2)*sin(angle))

my_grid2 <- base_grid %>%
  mutate(color=sample(c("#CFF09E","#A8DBA8","#79BD9A","#3B8686","#0B486B"), 
                      replace=T, size=nrow(my_grid)),
         angle = sample(seq(pi/2,2*pi,by=pi/2),
                        replace=T, size=nrow(my_grid)))  %>%
  mutate(xend=x+cos(angle),
         yend=y+sin(angle))

#
#my_grid %>% count(angle) %>% mutate(degree=180*angle/pi)

a <- my_grid %>% 
  sample() %>%
  ggplot(aes(x=x,y=y, color=color)) +
  geom_segment(aes(xend=xend,yend=yend, size=1), lineend="round") +
  geom_point(size=5) +
  scale_color_identity() +
  scale_size_identity() +
  xlim(c(1,20)) +
  ylim(c(1,20)) +
  coord_fixed() +
  theme_void()


b <- my_grid %>%
  sample() %>%
  ggplot(aes(x=x,y=y,color=color)) +
  geom_spoke(aes(radius=sqrt(2), angle=angle, alpha=x*y), lineend="round", size=5) +
  geom_spoke(aes(radius=sqrt(2), angle=angle+pi, alpha=x*y), lineend="round", size=5) +
  geom_spoke(aes(radius=sqrt(2), angle=angle+pi/2, alpha=-x*y), lineend="round", size=5,
             data=.%>% sample_n(size=100)) +
  geom_spoke(aes(radius=sqrt(2), angle=angle-pi/2, alpha=-x*y), lineend="round", size=5,
             data=.%>% sample_n(size=100)) +
  geom_point(color="#ffffffae") +
  scale_color_identity() +
  coord_fixed() +
  theme_void() +
  scale_alpha_continuous(range=c(0.5,0.9), guide="none") +
  xlim(c(1,20)) + ylim(c(1,20))


c <- my_grid %>%
  sample() %>%
  ggplot(aes(x=x,y=y,color=color)) +
  geom_spoke(radius=sqrt(2), angle=pi/4, size=3, alpha=0.9) +
  geom_spoke(radius=sqrt(2), angle=-pi/4, alpha=0.8, size=3) +
  scale_color_identity() +
  coord_fixed() +
  theme_void() +
  scale_alpha_continuous(range=c(0.5,0.9), guide="none") +
  xlim(c(1,20)) + ylim(c(1,20))

library(patchwork)
a+b+c

ggsave("geom_spoke_fun.png", width=27, height=9)