1172505 - hit region support broken for high resolution devices

Status: RESOLVED WONTFIX

(Core :: Graphics: Canvas2D, defect)

Description

[Jan Fiegert]

Attachment: hitregion-0.0.0.tgz

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:39.0) Gecko/20100101 Firefox/39.0
Build ID: 20150604162752

Steps to reproduce:

0. find a computer with a high-res (or retina) display, i used an 2014 MacBook Pro
1. open Firefox
2. open developer tools
3. check window.devicePixelRatio === 2
4. open the example from the attachment
5. move the mouse over the left or right eye 

6. cross check with an 'low-res' display ( window.devicePixelRatio === 1)



Actual results:

- the browser did not fire an event with event.region set


Expected results:

- the browser fires the event when you move the pointer over the region highlighted 
  by red circle

Comment 1

[Jan Fiegert]

Small correction regarding the EXPECTED RESULTS section:

- the browser shall fire an event with event.region set when moving the pointer over an eye.

Comment 2

[Jan Fiegert]

ensure that canvas.hitregions.enabled = true

Comment 3

[:Gijs (he/him)]

Confirming purely based on the fact that we already have a bug on file from someone who noticed the automated test for this was failing on their hidpi machine (but assumed that was a problem with the test rather than the code).

Rik, do you have time to look into this?

Comment 4

[Rik Cabanier]

No, I don't  have time at the moment :-(

Comment 5

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

Clear a needinfo that is pending on an inactive user.

Inactive users most likely will not respond; if the missing information is essential and cannot be collected another way, the bug maybe should be closed as INCOMPLETE.

For more information, please visit auto_nag documentation.

Comment 6

[:Gijs (he/him)]

Per bug 1780385 I think this code might be gone?

Comment 7

[Emilio Cobos Álvarez (:emilio)]

Yes