The X and Y flip flags can be applied through the stack consisting of:
- Object attributes
- Animation frame attributes
- OAM Data
Each of these negate eachother.
Confused yet? The same stack is traversed to obtain the final tile ID,
with an added layer on top for the base GFX offset and the offset for
the dynamically loaded GFX requested by the object!
wBattleAnimDelay is populated with the values passed to `anim_wait`.
It seems to be used as the "big" text entry cursor (i.e. for the bottom
3 buttons in the text entry screen).
It is never referenced explicitly, instead used when adding 1 to
SPRITEANIMSTRUCT_0E, in NamingScreen_AnimateCursor.
