confused about normal rotation matrix

[lifftel]

I am very confused about your rotation matrix to process the gt normal map

you use camera.R[0] @ [[-1,0,0][0, 1, 0][0, 0 ,-1]] @ gtnormal. I do not know where the [[-1,0,0][0, 1, 0][0, 0 ,-1]] obtained from?

[Mamba-ZJP]

Wanna know, as well.