Destroys this GeometryMask and nulls any references it holds.
Note that if a Game Object is currently using this mask it will not automatically detect you have destroyed it,
so be sure to call clearMask on any Game Object using it, before destroying it.
Restores the canvas context's previous clipping path, thus turning off the mask for it.
The Canvas Renderer instance being restored.
Sets the clipping path of a 2D canvas context to the Geometry Mask's underlying Graphics object.
The Canvas Renderer instance to set the clipping path on.
The Game Object being rendered.
The camera the Game Object is being rendered through.
Sets a new Graphics object for the Geometry Mask.
The Graphics object which will be used for the Geometry Mask.
This Geometry Mask
A Geometry Mask can be applied to a Game Object to hide any pixels of it which don't intersect a visible pixel from the geometry mask. The mask is essentially a clipping path which can only make a masked pixel fully visible or fully invisible without changing its alpha (opacity).
A Geometry Mask uses a Graphics Game Object to determine which pixels of the masked Game Object(s) should be clipped. For any given point of a masked Game Object's texture, the pixel will only be displayed if the Graphics Game Object of the Geometry Mask has a visible pixel at the same position. The color and alpha of the pixel from the Geometry Mask do not matter.
The Geometry Mask's location matches the location of its Graphics object, not the location of the masked objects. Moving or transforming the underlying Graphics object will change the mask (and affect the visibility of any masked objects), whereas moving or transforming a masked object will not affect the mask. You can think of the Geometry Mask (or rather, of its Graphics object) as an invisible curtain placed in front of all masked objects which has its own visual properties and, naturally, respects the camera's visual properties, but isn't affected by and doesn't follow the masked objects by itself.
GeometryMask is only supported in the Canvas Renderer. If you want to use geometry to mask objects in WebGL, see Phaser.GameObjects.Components.FilterList#addMask.