Screen should darken as launcher is revealed

[Mark Shuttleworth]

When the left edge launcher is revealed over an app or a scope other than the apps scope, the app should darken smoothly and proportionately to the revealing movement of the launcher.

At the moment, the screen darkens after the launcher is fully committed.

Instead the degree of darkening of the screen should be correlated to the extent of the launcher reveal. As the launcher is hinted, the screen should darken a little, and as it is revealed the rest of the darkening should happen, till the commit at which point the app / screen is at the final level of darkening.

If the left edge swipe continues then we expect to reveal the app scope, which would be undimmed and hence contrast strongly with the app (or other scope) that was visible.

This will serve to strengthen the hint / reveal of the launcher, and also to highlight the emergence of the app scope. It also matches the immediate dimming of the screen during a right-edge swipe.

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Proposed design

As explained in the description. Make the darkening overlay appearance proportional to the launcher reveal changing from opacity value 0 to 0.6.

During the long left edge swipe dark overlay should follow the dismissed app and finally disappear behind the right edge together with app while launcher fades away in place.

Special case: Apps scope on the screen initially
- overlay darkening should happen the same way during the launcher reveal as with any other application or scope.
- the special treatment happens in the long gesture during which the overlay should not move away towards right (because now there is no app dismissal). Instead the overlay should fade out in place. Fade out should follow the same animation timings as in normal case.
- note that the fade out should react to finger movement when the long swipe is active.

[Michael Zanetti (mzanetti)]

The darkening overlay has been removed completely as it doesn't work with convergence. Closing this as invalid.