Drawing Heart Shape & Revealing It

Happy_VDay.r

## drawing heart! 
library(tidyverse)
library(gganimate)


## function to create data frame for heart shape with 100 points. 
heart_vertices <- function(xc=0,yc=0,npoints=100,...){
  t = seq(-pi,pi, length.out=npoints+1)
  x = xc + 16 *(sin(t))^3
  y = yc + 13*cos(t) - 5*cos(2*t) - 2*cos(3*t) - cos(4*t)
  df <- tibble(theta=t,x=x,y=y) 
  return(df)
}
## make the data frame for heart
heart_df <- heart_vertices()

## reveal the heart with gganimate transtion_reveal!
heart_df %>%
  ggplot(aes(x=x,y=y)) +
  geom_polygon(fill="#E35B5D90") +
  geom_path(color="#E35B5D", size=10) +
  annotate(label="Happy\nValentine's\nDay", 
           color="white", family="Helsinki", geom="text", x=0,y=0, size=15,
           lineheight=0.8) +
  theme_void() +
  transition_reveal(along=theta)