Outlining areas of a map using rectangles-CodePudding

I have created a map of Newfoundland, Canada and wish to highlight Trinity Bay. I was trying to do this using geom_rect. It is working for me (red rectangle), although I would like to rotate the rectangle so that it contains just the bay, and none of the surrounding land (like the orange rectangle). Here is my code:

library(ggplot2)
Provinces <- getData("GADM", country="CAN", level=1)

d <- ggplot()  
  geom_polygon(data=Provinces, aes(long, lat, group=group), colour="grey10", 
           fill="cadetblue1", alpha=0.8)  
  coord_map(xlim=c(-60, -52), ylim=c(46, 52))  
  theme_bw() 
  geom_rect(aes(xmin=-53, xmax=-53.75, ymin= 47.5, ymax=48.5), alpha=0, 
        colour="red", size=1, linetype=1)
d

Any suggestions? Thanks in advance!

CodePudding user response：

Use geom_polygon() instead of _rect(). Define the parameters and pass in. It requires playing around with the parameters, but is easy to do - My machine is playing up, and it's taking too long to get it over the bay as you want.

poly <- tibble(x = c(-53.75, -53, -52, -52.75), y = c(47.5, 47.5, 48.5, 48.5))

d <- ggplot()  
  geom_polygon(data=Provinces, aes(long, lat, group=group), colour="grey10", fill="cadetblue1", alpha=0.8)  
  coord_map(xlim=c(-60, -52), ylim=c(46, 52))  
  theme_bw() 
  geom_polygon(data = poly, aes(x = x, y = y), alpha=0, colour="red", size=1, linetype=1)

CodePudding user response：

Not an expert here but could you perhaps use the arguments hjust and vjust within geom_rect?