How to access the position activated grids from the touch_grid plugin?

[kevinqyh0827]

Hi, everyone. I was using the touch_grid plugin (https://github.com/google-deepmind/mujoco/tree/main/plugin/sensor) and wonder how to access the positions of the activated grid (like read squares from this video: https://www.youtube.com/watch?v=0LOJ3WMnqeA), so that I could compare to the default contact detection results. Thanks so much!