[whatwg] <link rel=icon width="" height="">

[Jeff Walden]

Ian Hickson wrote:
>> This is a proposal to add "height" and "width" attributes to <link>
>> specifically for the case of rel=icon, so that authors can provide
>> multiple icons and let the UA decide which to use based on their size
>> (without having to download them all to find out which is best).
>>
>> Opinions?

Given that <link/> is more intended as a generic element, I'm somewhat leery of adding attributes specifically for one individual use of it.  If you're going to add an attribute (but see below), I think it makes sense that it be something that any use of <link/> could use to store extra data -- so an opaque attribute whose semantics are specified by the rel attribute of the link.


Maciej Stachowiak wrote:
> I would suggest a sizes attribute which can take a list of sizes (with x as a width/height separator), or a keyword such as "any" or "scalable" to indicate a scalable format suitable for any size.
>
> <link type="icon" type="application/svg" sizes="any" href="whatwg.svg">
> <link type="icon" type="image/microsoft.vnd.icon" sizes="16x16 32x32" href="whatwg.ico">
> <link type="icon" type="image/x-apple-icons" sizes="16x16 32x32 64x64 128x128 256x256 512x512" href="whatwg.icns">
> <link type="icon" type="image/png" sizes="59x60" href="whatwg.png">

This might require that existing browsers cope correctly (or exploit duplication/error behaviors), but could a MIME parameter address this without needing another attribute at all?  That's the most narrowly scoped change I can imagine that would address the need.

> <link rel="icon" type="application/svg; sizes=any" href="whatwg.svg">
> <link rel="icon" type='image/microsoft.vnd.icon; sizes="16x16,32x32"' href="whatwg.ico">
> <link rel="icon" type='image/x-apple-icons; sizes="16x16,32x32,64x64,128x128,256x256,512x512"' href="whatwg.icns">
> <link rel="icon" type="image/png; sizes=59x60" href="whatwg.png">

Restrictions on what a parameter value may be (basically can't contain any separators or whitespace) are a touch confounding here because you don't have any separators unless you quote; that probably factors into the equation here.

Jeff

-- 
Life would be so much easier if humans had a natural affinity for remembering 128-bit integers.