library(tidyverse)
library(ggforce)
library(patchwork)
library(ggthemes)


df <- tibble(
  t = seq(0,2*pi,length.out=61)
) %>% mutate(idx=row_number(),
             m = sqrt((idx%%2)+0.1),
             x = m*cos(t),
             y = m*sin(t))

df %>%
  filter(idx<nrow(df)) %>%
  ggplot(aes(x=x,y=y,group=idx%%3)) +
  geom_bspline_closed(radius=unit(2,"mm"), aes(fill=idx%%3), n=20) +
  geom_bspline_closed(expand=unit(2,"mm"), aes(fill=idx%%3), n=20) +
  coord_fixed() +
  theme_void() +
  scale_fill_viridis_c(alpha=0.3, end=0.8, option="magma", guide="none")


df %>%
  filter(idx<nrow(df)) %>%
  ggplot(aes(x=x,y=y)) +
  geom_bspline_closed(radius=unit(2,"mm"), n=1000, alpha=0.2) +
  geom_bspline_closed(expand=unit(-2,"mm"), n=1000, alpha=0.8) +
  coord_fixed() +
  theme_void() +
  scale_fill_viridis_c(alpha=0.3, end=0.8, option="magma", guide="none") +
  geom_point(size=0.5) +
  geom_path(size=0.2) +
  geom_shape(size=0.3, expand=unit(-2,"mm"))