Input Team

The Chromium Input team (aka input-dev) is a web platform team focused on making touch (P1) and other forms of input (P2) awesome on the web.  High-level goals:

• Measure & improve input-to-paint latency. Web pages should stick to your finger!
• Reduce web-developer pain points around input and scrolling, including improving interoperability between browser engines, predictability, simplicity and consistency between chromium platforms.
• Enable high-performance rich touch interactions (such as pull-to-refresh) on the web.
• Ensure Chrome UI features driven by input over the contents area provide a great experience to both end-users and web developers.
• Enable the productivity of any chromium developer working with input-related code through effective code ownership and code health initiatives.

See also our concrete quarterly objectives.

 

Contacts

input-dev@chromium.org is our mailing list, and we sometimes use the #chromium-input-dev IRC channel on Freenode. 

 

Useful bug queries

• Hotlist-InputDev - all (or most) bugs we're tracking
• Other potentially relevant labels: Cr-Blink-Input, Cr-Blink-Scroll or Cr-Internals-Input-Touch-Screen categories
• Available bugs
• Code cleanup ideas

Key Learning Resources

• Chromium touch pipeline overview
• Scrolling in blink
• Android tracing cheat sheet
• Blink coordinate spaces
• Touch events specification - current draft
• W3C public-touchevents archive
• Touch event behavior details across browsers
• Issues with touch events
• Rick Byers' G+ stream
• Debugging common website touch issues

Design Docs

• Chromium input latency tracking
• Scroll-blocks-on: scrolling performance vs. richness tradeoff
• Chromium throttled async touchmove scrolling
• Gesture Recognition
• Vsync-aligned buffered input
• Touchpad and Wheel Latching
• Touchpad pinch zoom
• User Activation v2
• How Chrome uses user gestures (May 2017)
• Case study: Popup with user-activation across browsers (May 2017)
• User Activation v2: Main design (May 2017)
• User Activation v2 with site isolation (May 2018)
• Input for Worker:
• Initial design discussion: Low-latency Event Handling in Worker (July 2017)
• JS API proposals for Routing Worker Events through the Compositor Thread (July 2017)
• Plumbing mouse as mouse on Android (October 2016)
• Coalesced Events (October 2016)
• TODO: more

Presentations / talks

• Extensible Scrolling - BlinkOn 3 (Nov 2014):  slides, video
• Smooth to the touch: chromium's challenges in input on mobile - BlinkOn 2 (May 2014)
• Input - BlinkOn 1 (Sept 2013)
• Point, click, tap, touch - Building multi-device web interfaces - Google I/O 2013