[whatwg] Canvas Proposal: aliasClipping property

[Charles Pritchard]

There have been a few discussions about anti-aliasing / aliasing in 
Canvas implementations.
Of those I read through, the conflict remains.

In some implementations: when drawImage is used along with a clipping path,
feathering is applied. This shows up in several projective 
transformation demos
contrasting Firefox with Chrome.

I believe that if we allow a toggle for this setting, we can bring some 
compatibility
to the two systems.

Enumerate two aliasClipping values : "aliased", "feathered"

I consider "anti-aliased" to confusing, I think "feathered" is a better 
name.

.....

[Supplemental]
interface CanvasRenderingContext2D {
     attribute DOMString aliasClipping; // default "feathered"
  }

context . aliasClipping [ = value ]

     Returns the current aliasing of the clipping region, as applied to 
rendering operations.

     Can be set, to change the aliasing value.

     If any of the arguments are not implemented, throws a 
NOT_SUPPORTED_ERR exception.

CanvasRenderingContext2D.prototype.defineSetter('aliasClipping') { throw 
NOT_SUPPORTED_ERR; }