[R] Plotting symbols over a screenshot

[Ralf B]

Hi all,

I would like to generate a very simple visualization in R and wonder
if somebody here could tell me about a simple script that can do
exactly that.

Input: I have about 1000-3000 screen coordinates of mouse movements
and mouse click positions in a data.frame (each collumn for each data
type) and an screenshot picture in png.

Output: I would like to visualize mouse movements as cycles and mouse
clicks as squares. Background should be the picture. Foreground the
cycles and squares.

What is the simplest way to do this? (single command?) It does not
need to be fast, but should work decent for 1000-5000 points.

Thanks a lot,
Ralf