The base filter class, you can extend it in order to define your own filters, although ShaderFilter will be the most straightforward way to define simple custom filter.

Keep in mind that filters use internal Object resolution to render its content, hence scaling of the filtered object would not increase the rendering resolution. For example, 20x20px Bitmap with scale = 2 will render onto 20x20 filter texture if filter is attached to it directly, but if filter is attached to the parent of that bitmap, filter will render 40x40 texture.
Another thing to be aware of, is that Scene.scaleMode does not affect filter resolution either, and upscaling contents with scaleMode would not upscale the resolution of filtered content.

Filters limit their render area dictated by bound object boundaries, Filter.autoBounds and Filter.boundsExtend variables and Filter.getBounds method. See their respective docs for details.

For optimization purposes, rendering boundaries are clipped by scene viewport and nothing will be rendered offscreen.

Variables

@:value(true)autoBounds:Bool = true

When enabled, rendering bounds of the filter will be expanded by Filter.boundsExtend in all directions. Otherwise filter should provide custom bounds through Filter.getBounds call.
Default : true.

@:value(0.)boundsExtend:Float = 0.

Rendering texture boundaries extent. Increases the rendering area by twice the Filter.boundsExtend value.
Automatically applied to object bounds when autoBounds = true or Filter.getBounds is not overridden.
Does not affect boundaries when autoBounds = true and boundsExtend is less than 0.

@:value(true)@:isVarenable:Bool = true

When filter is disabled, attached object will render as usual.

@:value(false)smooth:Bool = false

When enabled, some filters will use bilinear filtering on temporary textures.
Does not affect the majority of filters.

See also:

Methods

bind(s:Object):Void

Sent when filter is bound to an Object s. If Object was not yet allocated, method will be called when it's added to allocated Scene.

draw(ctx:RenderContext, input:Tile):Tile

Renders the filter onto Texture in input Tile.

getBounds(s:Object, bounds:Bounds):Void

Method should populate bounds with rendering boundaries of the Filter for Object s. Initial bounds contents are undefined and it's recommended to either clear them or call s.getBounds(s, bounds). Only used when Filter.autoBounds is false. By default uses given Object bounds and extends them with Filter.boundsExtend. Compared to autoBounds = true, negative boundsExtend is still applied, causing rendering area to shrink.

sync(ctx:RenderContext, s:Object):Void

Used to sync data for rendering.

unbind(s:Object):Void

Sent when filter was unbound from an Object s. Method won't be called if Object was not yet allocated.