The coordinate positions difference between points() and geom_point()

[chenjy327]

Hi:
When i was using as.ggplot() convert points() to ggplot objects, then add some points with geom_point() in the plots, i found that the points drawn using points() and geom_point() are in different positions.

Here is my code:

plot_f <- function(){
          plot.new()
          points(df[, 1:2], cex=0.6, col=2, pch=2)
       }
 p <- as.ggplot(
          ~plot_f()
       )
     
  p <- p +
          geom_point(
         data = df,
         aes(x = df[,1], y = df[,2]),
          size = 4
        )

df is a data frame :

the result p is:

Could you tell how to solve the problem?

Thanks!