Open Bug 1753724 Opened 3 years ago Updated 8 months ago

`pointermove` events returned by `getCoalescedEvents()` report `.movementX` and `.movementY` in absolute values, rather than relative to the previous event

Categories

(Core :: DOM: UI Events & Focus Handling, defect, P3)

Product:
Core
Component:
DOM: UI Events & Focus Handling
Version:
Firefox 98
Type:
defect

Tracking

()

Status:
UNCONFIRMED

People

(Reporter: alex.forrence, Unassigned)

References

Details

Steps to reproduce:

  1. Navigate to https://codepen.io/aforren1/pen/abVmEyZ for test case
  2. Toggle "mousemove (off)/pointermove (on)" on, and move mouse slowly
  3. Toggle "uncoalesce?" on, and move mouse slowly

Actual results:

In step 3, dx and dy report absolute position on page, rather than the relative position.

Expected results:

The values of dx and dy in step 3 should be relative to the previous cursor position, not absolute (approximately matching the magnitude and signs of 'mousemove' & coalesced 'pointermove').

The Bugbug bot thinks this bug should belong to the 'Core::Layout: Positioned' component, and is moving the bug to that component. Please revert this change in case you think the bot is wrong.

Component: Untriaged → Layout: Positioned
Product: Firefox → Core
Component: Layout: Positioned → DOM: UI Events & Focus Handling
Severity: -- → S3
Priority: -- → P3

I could reproduce this with Firefox Nightly 100.0a1 on macOS 12.1.

The fun thing is that movementX/Y should be 0 always with pointer events per current specifications.

https://w3c.github.io/pointerlock/#dom-mouseevent-movementx

movementX/movementY must be zero for all mouse events except mousemove

Huh, fun indeed.

It has been clarified that this also includes pointermove.
See the following GitHub issue.

You need to log in before you can comment on or make changes to this bug.