what the meaing and usage of setFlipX and setFlipY

cocos2d-x C++
1

Today when I read the codes of tests in ZwoptexTest.cpp, I saw function like sprite~~>setFlipX or sprite~~>setFlipY(false).

I wonder what is thier meaning and what function they have.

2

setFlipX: let sprite rotate around the x-axis
setFlipY: let sprite rotate around the y-axis