Re: Merging spif-2 branch

[Bill Haneman <Bill Haneman Sun COM>]

Havoc Pennington wrote:

> ...
>
> What I'm saying is that I think you guys are in a bad spot until/unless
> there's more API for communication with the compositing manager.
>  
I agree 100%.

I don't mind putting the core a11y features, or at least some of the 
rendering mods, into metacity, either directly or as some kind of 
plugin.  Seems like a good approach, if you don't mind having to deal 
with the consequences (i.e. public API in the WM, plugins tickling your 
code, etc.).

> ...
>
> I don't agree with Keith I guess, it doesn't make sense to me. To make a
> CM worth doing at all it should essentially be an extension of the
> current drawing APIs to a much more powerful set of operations, and apps
> need to be able to rely on those. That means a pretty complex CM and it
> means that apps will come to rely on the CM existing in order to work.
> Maintaining an alternate CM would be like having special X drivers or a
> special X server for a11y.
>
> Just seems to set a11y up to fail.
>
> The approach that makes sense to me is that the CM or WM just has a
> magnifier built into it, and settings to disable whatever alpha needs
> disabling. Or if the CM is someday flexible enough, the magnifier could
> be another client of it. But having the magnifier in the CM process
> doesn't seem crazy to me in the meantime.
>  
Yeah; the basic things we need are

1) rescaling of windows/contents on render, i.e. basic magnification;
2) some pluggable scaling architecture so we could plug in some new kind 
of scaling other than nearest-neighbor and the various interpolations 
(for instance, a "hard edge" contouring scaler, which would do font 
smoothing without making things blurry);
3) some sort of multi-pass rendering system for the above, in instances 
where the pixops are too compute-intensive to inline them by default;
4) control over the RGBA mapping on render, so that colors can be 
reversed, contrast increased, alphas mucked with, etc.
5) Some way to bypass the above for font rendering, so that we can use 
the built-in scaling capabilities of our fonts instead.

So, not entirely trivial except for #1.

Bill

> I don't think this will bite you for 2-4 years since the CM won't be
> widely used very quickly, but if investing a lot of energy in a
> magnifier, it might be worth getting right the first time, at least in
> rough outline.
>  
Agreed.

Bill

> Havoc
>
>
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