This is the base class for creating a PIXI filter. Currently only webGL supports filters. If you want to make a custom filter this should be your base class.
The fragment source in an array of strings.
An object containing the uniforms for this filter.
Syncs the uniforms between the class object and the shaders.
Array an array of filter objects
An array of passes - some filters contain a few steps this array simply stores the steps in a liniear fashion. For example the blur filter has two passes blurX and blurY.