Members
| Rotation | Direction |
|---|---|
| 0° | East |
Reflection about the main diagonal.
Reflection about X-axis.
Reflection about Y-axis.
| Rotation | Direction |
|---|---|
| -90°/270°↻ | North |
| Rotation | Direction |
|---|---|
| -45°/315°↻ | Northeast |
| Rotation | Direction |
|---|---|
| -135°/225°↻ | Northwest |
Reflection about reverse diagonal.
| Rotation | Direction |
|---|---|
| 90°↻ | South |
| Rotation | Direction |
|---|---|
| 45°↻ | Southeast |
| Rotation | Direction |
|---|---|
| 135°↻ | Southwest |
| Rotation | Direction |
|---|---|
| 180° | West |
Methods
Composes the two D8 operations.
Taking ^ as reflection:
| E=0 | S=2 | W=4 | N=6 | E^=8 | S^=10 | W^=12 | N^=14 | |
|---|---|---|---|---|---|---|---|---|
| E=0 | E | S | W | N | E^ | S^ | W^ | N^ |
| S=2 | S | W | N | E | S^ | W^ | N^ | E^ |
| W=4 | W | N | E | S | W^ | N^ | E^ | S^ |
| N=6 | N | E | S | W | N^ | E^ | S^ | W^ |
| E^=8 | E^ | N^ | W^ | S^ | E | N | W | S |
| S^=10 | S^ | E^ | N^ | W^ | S | E | N | W |
| W^=12 | W^ | S^ | E^ | N^ | W | S | E | N |
| N^=14 | N^ | W^ | S^ | E^ | N | W | S | E |
| Name | Type | Description |
|---|---|---|
rotationSecond |
PIXI.GD8Symmetry |
Second operation, which is the row in the above cayley table. |
rotationFirst |
PIXI.GD8Symmetry |
First operation, which is the column in the above cayley table. |
Returns:
| Type | Description |
|---|---|
| PIXI.GD8Symmetry | Composed operation |
Approximates the vector V(dx,dy) into one of the
eight directions provided by groupD8.
| Name | Type | Description |
|---|---|---|
dx |
number |
X-component of the vector |
dy |
number |
Y-component of the vector |
Returns:
| Type | Description |
|---|---|
| PIXI.GD8Symmetry | Approximation of the vector into one of the eight symmetries. |
| Name | Type | Description |
|---|---|---|
rotation |
PIXI.GD8Symmetry |
symmetry whose opposite is needed. Only rotations have opposite symmetries while reflections don't. |
Returns:
| Type | Description |
|---|---|
| PIXI.GD8Symmetry | The opposite symmetry of rotation |
Checks if the rotation angle is vertical, i.e. south or north. It doesn't work for reflections.
| Name | Type | Description |
|---|---|---|
rotation |
PIXI.GD8Symmetry |
The number to check. |
Returns:
| Type | Description |
|---|---|
| boolean | Whether or not the direction is vertical |
Helps sprite to compensate texture packer rotation.
| Name | Type | Description |
|---|---|---|
matrix |
PIXI.Matrix |
sprite world matrix |
rotation |
PIXI.GD8Symmetry |
The rotation factor to use. |
tx |
number |
sprite anchoring |
ty |
number |
sprite anchoring |
Adds 180 degrees to rotation, which is a commutative operation.
| Name | Type | Description |
|---|---|---|
rotation |
number |
The number to rotate. |
Returns:
| Type | Description |
|---|---|
| number | Rotated number |
Reverse of add.
| Name | Type | Description |
|---|---|---|
rotationSecond |
PIXI.GD8Symmetry |
Second operation |
rotationFirst |
PIXI.GD8Symmetry |
First operation |
Returns:
| Type | Description |
|---|---|
| PIXI.GD8Symmetry | Result |
| Name | Type | Description |
|---|---|---|
ind |
PIXI.GD8Symmetry |
sprite rotation angle. |
Returns:
| Type | Description |
|---|---|
| PIXI.GD8Symmetry | The X-component of the U-axis after rotating the axes. |
| Name | Type | Description |
|---|---|---|
ind |
PIXI.GD8Symmetry |
sprite rotation angle. |
Returns:
| Type | Description |
|---|---|
| PIXI.GD8Symmetry | The Y-component of the U-axis after rotating the axes. |
| Name | Type | Description |
|---|---|---|
ind |
PIXI.GD8Symmetry |
sprite rotation angle. |
Returns:
| Type | Description |
|---|---|
| PIXI.GD8Symmetry | The X-component of the V-axis after rotating the axes. |
| Name | Type | Description |
|---|---|---|
ind |
PIXI.GD8Symmetry |
sprite rotation angle. |
Returns:
| Type | Description |
|---|---|
| PIXI.GD8Symmetry | The Y-component of the V-axis after rotating the axes. |