Namespace groupD8

Implements the dihedral group D8, which is similar to [group D4]http://mathworld.wolfram.com/DihedralGroupD4.html; D8 is the same but with diagonals, and it is used for texture rotations.

The directions the U- and V- axes after rotation of an angle of a: GD8Constant are the vectors (uX(a), uY(a)) and (vX(a), vY(a)). These aren't necessarily unit vectors.

Origin: This is the small part of gameofbombs.com portal system. It works.

Ivan

PIXI.groupD8

PIXI

Variables

E
MAIN_DIAGONAL
MIRROR_HORIZONTAL
MIRROR_VERTICAL
N
NE
NW
REVERSE_DIAGONAL
S
SE
SW
W

Functions

add
byDirection
inv
isVertical
matrixAppendRotationInv
rotate180
sub
uX
uY
vX
vY