1806829 - [Unity WebGL for Firefox] When a WebGL window has the cursor locked, mouse input drifts to the right

Status: UNCONFIRMED

(Core :: Graphics: CanvasWebGL, defect)

Description

[PHATASSSTUDIOS]

Attachment: Simple WebGL build demonstrating the bug - click inside and check the browser console.

Steps to reproduce:

Build a simple Unity WebGL app that locks the cursor to the app and logs mouse input delta to console.
Open the browser console and ensure the cursor is locked by the APP. Input drifting starts the moment cursor is locked, and stops immediately when the cursor is released with ESC.
[Included simple WebGL build that locks the mouse and logs input delta to console for testing]
(Untested with other forms of WebGL, but doesn't happen with Unity WebGL + other browsers)

Actual results:

Mouse input delta erratically drifts to the right (positive X axis)
E.G. if the mouse is stationary, WebGL reports ghost movement values of ~0.1 on roughly alternating frames

APPARENTLY this also happens while mouse is moving, but it's harder to measure.

Expected results:

Mouse input delta should reflect hardware mouse movement reliably: non-moving mouse should produce (x:0.0, y:0.0) movement deltas

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::Graphics: CanvasWebGL' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[BugBot [:suhaib / :marco/ :calixte]]

The severity field is not set for this bug.
:jgilbert, could you have a look please?

For more information, please visit auto_nag documentation.