Features/Tick based animation

Summary

Smoother Animations.

Animate each frame as Gtk+ needs a new frame drawn instead of at whatever frame rate we want.

Owner

• Name: Sam P.
• Email: *@sam.today

Current status

• Targeted release: 0.108
• Last updated: 5 October 2015
• Percentage of completion: 75%

Detailed Description

Gtk+ 3.8 introduces the idea of a 'tick'. This can have a callback attached to it. This is used to do animations in GtkPopover and the other Gtk+ widgets that have animations. Therefore, sugar should not just do out animations at 20fps. If the animation could go at 120fps because the computer is awesome, why not? If the computer is bad and it can only render 5fps, why worry about any more?

This feature can be split up into many parts:

• Toolkit implementation (100%): https://github.com/sugarlabs/sugar-toolkit-gtk3/pull/213
• Frame and Home view (100%): https://github.com/sugarlabs/sugar/pull/505 Frame and homeview are a good spot for tick based animation as we are not cpu bound to open the frame or change views - the animation can take up 100% cpu and all will be fine
• Pulsing icon (NO-GO): https://github.com/sugarlabs/sugar/pull/513 Opening an activity is a cpu bound task, so this is probably the wrong space for animations that steal all of the cpu. This patch TRIPLES activity start times on the XO4.

Benefit to Sugar

Smoother animation.

No legit, that is the only benefit.

Scope

Animation consumers need to add the "widget=x" when creating an animator so they can have the tick callback attached.

Consumers who don't are not effected.

UI Design

None

How To Test

https://github.com/sugarlabs/sugar-toolkit-gtk3/pull/258#issuecomment-145695297

User Experience

Smoother animations.

Dependencies

Needs Gtk 3.8 to look different.

Contingency Plan

None necessary, revert to previous release behaviour

Documentation

Included in the toolkit patch

Release Notes

Animations are now smoother than ever on newer hardware. Animations dynamically change FPS to leave no cpu cycle wasted.

Comments and Discussion

https://github.com/sugarlabs/sugar-toolkit-gtk3/pull/258 https://github.com/sugarlabs/sugar/pull/572