Directional blur filter. Takes source image and direction buffer inputs
Should the blur window be centered, default is false
Post-blur gain, default is 1.0
Should filter use directions perpendicular to those in the direction buffer? default is false
Spread multiplier: the distance in pixels between sampled pixels. The default is 1.0
The sample window: how many samples to mix. The default is 5
Wrap around left and right edges
Wrap around top and bottom edges