[whatwg] Bicubic filtering on context.drawImage

Rik Cabanier cabanier at gmail.com
Mon Dec 9 10:22:09 PST 2013

On Mon, Dec 9, 2013 at 7:06 AM, Glenn Maynard <glenn at zewt.org> wrote:

> On Mon, Dec 9, 2013 at 1:21 AM, Tab Atkins Jr. <jackalmage at gmail.com>
> wrote:
> > Hm, I wonder if image-interpolation on the <canvas> should affect
> > this?  It's defined to only have an effect when you scale the <canvas>
> > element itself, but I think it probably makes sense that whatever
> > scaling intent you specify for the element should probably apply to
> > images you draw into it with a scale.
> >
> What is "image-interpolation"?  It looks like a CSS property, but Google
> doesn't distinguish between "image-interpolation" and "image
> interpolation", so it's impossible to search for.
> If it is, having CSS state affect drawing of 2d canvas seems wrong.  Aside
> from the bad layering, it would lead to different rendering if you draw to
> a Canvas before stylesheets finish loading (equivalent to not waiting for
> images, but much easier to get wrong without noticing), and if you
> offscreen render a Canvas before actually putting it in a document.

Yes, CSS properties should not affect 'drawImage'.
The spec currently doesn't enforce what resampling algorithm to use; it
just allows you to turn it off.

Tingan, would it be acceptable for you to do the resampling in JavaScript?

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