Comment 5 for bug 931883

On Tue, 14 Feb 2012, Daniel van Vugt wrote:

> Paint layers sounds good. Don't be afraid of overdraw (instead of
> clipping) because that's what allows high-performance rendering in games
> etc.
>
> I have been thinking a "shadow" plugin would be the most elegant solution;
> 1. Start with a simple implementation that just renders a grey rectangle before rendering each window.

You would have to clip out the grey rectangle.

> 2. Get the stacking order right -- draw window and shadow layers back-to-front.
> 3. Implement smooth gradients (Gaussian?).
>
> I would expect some fixes required in core here and there, but mostly
> shadows can be the sole job of a new plugin.
>

Well, we can't add plugins at this point because of the problems
encountered at changing the user's configuration plus its after FF.

I think what we can do for now is, draw the shadow using the clip region
created by outputRect n inputRect on one layer and then draw the window
/with/ a clipped shadow using inputRect as the clip region (transformed
using glDrawGeometry.

wdyt?

> --
> You received this bug notification because you are a member of Compiz
> Maintainers, which is the registrant for Compiz Core.
> https://bugs.launchpad.net/bugs/931883
>
> Title:
> Improve performace of the shadow clipping code
>
> Status in Compiz Core:
> Confirmed
>
> Bug description:
> This branch is a starter lp:~smspillaz/compiz-core/compiz-
> core.fix_slow_movement
>
> To manage notifications about this bug go to:
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>