Re: Updated IFT Demo

Nice! Particularly pleased to see both CFF2 and glyf in the demo.

A couple of things I noticed:

On the Variable Design Space Augmentation Example page, in Firefox 
(Nightly 139.0a1) I am not seeing condensed fonts being used with IFT, 
while they are used with unicode-range. On Chrome (Canary 137.0.7144.0) 
the IFT and unicode-range renderings both use condensed.

It would be helpful for the Simplified Chinese pages to mention in 
English what thy are showing.

On 2025-04-24 20:50, Garret Rieger wrote:
> Previously we had a wasm based demo of IFT that was built on a 
> prototype (non spec compliant) version of the technology. I've just 
> upgraded that demo to use the latest encoder 
> <https://github.com/w3c/ift-encoder> and client 
> <https://github.com/googlefonts/fontations/tree/main/incremental-font-transfer> implementations, 
> which are both compliant with the latest specification draft.
>
> You can find the updated demo here: 
> https://garretrieger.github.io/ift-demo/
>
> Notable changes:
>
>   * Most importantly the demo is now compliant with the latest IFT
>     specification draft <https://w3c.github.io/IFT/Overview.html>.
>   * For the text samples using Roboto, the previous demo used a table
>     keyed only encoding. Now it's using a mixed (glyph and table
>     keyed) encoding. The glyph keyed segmentation was generated using
>     the experimental closure based segmenter
>     <https://github.com/w3c/ift-encoder/blob/main/docs/experimental/closure_glyph_segmentation.md>.
>     Performance (in terms of # of bytes transferred) is looking good
>     so far.
>   * For the CJK fonts the demo extends both CFF2 (Noto Serif SC) and
>     glyf (Noto Sans SC) fonts. The prior version did not include any
>     CFF fonts.
>   * The previous demo included an example of layout feature extension,
>     that's been removed for now as the encoder does not yet fully
>     support that use case yet. I'll be getting that added back in once
>     I get support finished in the encoder.
>
> I'm planning to make some more improvements to this over time including:
>
>   * Utilize codepoint frequency data when generating the glyph
>     segmentations for Roboto.
>   * Improvements to the encodings (such as using table keyed patch
>     preload lists).
>   * General performance improvements.
>   * Demonstration of layout feature extension.
>
> Lastly, if you're interested in more details about how the IFT 
> encodings for the font are created, the demo repository contains all 
> of the code necessary to generate the IFT font encodings: 
> https://github.com/garretrieger/ift-demo/blob/main/Makefile

-- 
Chris Lilley
@svgeesus@mastodon.scot
Technical Director @ W3C
W3C Technical Programming Team, Core Web Design