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Re: [filters] Shading language recommendation

From: Dean Jackson <dino@apple.com>
Date: Wed, 22 Aug 2012 07:03:25 +1000
Cc: "public-fx@w3.org" <public-fx@w3.org>
Message-id: <02ED79AA-682E-471D-88BF-CCCADAF7E41C@apple.com>
To: Sylvain Galineau <sylvaing@microsoft.com>

On 22/08/2012, at 2:52 AM, Sylvain Galineau <sylvaing@microsoft.com> wrote:

> The normative prose of section 38.2 'Recommended shading language' recommends 
> GL SL ES [1]. Per RFC2119 this means implementers MUST support GL SL ES 
> unless there exist 'valid reasons in particular circumstances' to ignore this 
> recommendation. 
> 
> While Microsoft has no objection to defining how the feature works for UAs 
> that choose GL SL ES as defined by Web GL 1.0, we object to its normative
> recommendation.

Can you explain why you object? You mention below what you'd prefer, but don't
provide reasoning.

The informative section related to media codecs is there because there are
well-known IP issues around that technology. As far as I am aware, this does
not apply in the case of shading languages.

Also, don't you (Microsoft) agree there is a significant penalty if we don't require
a single shading language? What is it in particular about GLSL that you object
to?

Dean

> This was the reason for the note in the same section, note
> which looks at best confusing if not contradictory given the normative 
> recommendation that precedes it.
> 
> We would prefer to follow a pattern similar to the informative section 6.1 in 
> Media Source Extension[2]: "This section defines segment formats for 
> implementations that choose to support WebM". We think the ability to specify 
> multiple shading languages is important, as broadly suggested by the current 
> note. This allows sites to work with different user agents supporting different 
> shading languages. For example, a future version of GL SL ES with fallback to 
> the current version for user agents that don't yet support the new version.
> 
> 
> [1] https://dvcs.w3.org/hg/FXTF/raw-file/tip/filters/index.html#recommendation
> [2] http://dvcs.w3.org/hg/html-media/raw-file/tip/media-source/media-source.html
> 
> 
> 
Received on Tuesday, 21 August 2012 21:03:58 GMT

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