[solved] What are mirror sprites?

[Layz]

aha, I had a feeling that they may be used for that...

but what should I do if I want to use a mirrored sprites, in the data changer, for example:

<bmp_begin>
name: Deep
head: sprite\sys\deep_f.bmp
small: sprite\sys\deep_s.bmp
file(0-69): sprite\sys\deep_0.bmp w: 79 h: 79 row: 10 col: 7
file(70-139): sprite\sys\deep_1.bmp w: 79 h: 79 row: 10 col: 7
file(140-209): sprite\sys\deep_2.bmp w: 79 h: 79 row: 10 col: 7
walking_frame_rate 3

This is from Deep dat file, he has mirrored sprites but they are not written anywhere in the data, how does the EXE recognize whether this char has mirrored sheets or no?