Bug 275100 – CanvasBase owns a ImageBuffer that belongs to the CanvasRenderingContext

• Status: NEW
• Component: Canvas

[Kimmo Kinnunen]

CanvasBase owns a ImageBuffer that belongs to the CanvasRenderingContext

This is a problem because only CanvasRenderingContext2DBase really uses the ImageBuffer. Others would be better performing if the CanvasBase didn't have a ImageBuffer, rather the buffer was asked from the context.

[Radar WebKit Bug Importer]

<rdar://problem/129208981>

[Simon Fraser (smfr)]

> the buffer was asked from the context
This seems backwards. The buffer vends the context.

[Kimmo Kinnunen]

(In reply to Simon Fraser (smfr) from comment #2)
> > the buffer was asked from the context
> This seems backwards. The buffer vends the context.

The intention was to say "the |drawing or display] buffer copy was asked from the [canvas rendering] context". In this context "buffer vends the context" doesn't make sense.

The specific variant of canvas rendering context should return the rendering results image, it is private logic of said rendering type.

The specific variant of canvas rendering context should manage the drawing buffer backing store in the manner it needs to manage it.