Mouse wheel zooms too fast in FF

[klimashkin]

One mousewheel zooms page 3 times.
Leaflet 0.6, FF 22

[mourner]

Yep, @jfirebaugh is now investigating that issue...

[jfirebaugh]

@klimashkin can you run this and post the results along with what mouse hardware you have?

[klimashkin]

OK
Windows 7, FF22, Mousewheel

Mozilla/5.0 (Windows NT 6.1; WOW64; rv:22.0) Gecko/20100101 Firefox/22.0
wheel: deltaY=3, deltaMode=1

[jfirebaugh]

Results

Ubuntu, FF 22, Trackpad (same with scroll mouse):

Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:22.0) Gecko/20100101 Firefox/22.0
wheel: deltaY=3, deltaMode=1

Windows, FF 22, Mouse:

Mozilla/5.0 (Windows NT 6.1; WOW64; rv:22.0) Gecko/20100101 Firefox/22.0
wheel: deltaY=3, deltaMode=1

MacOS, FF 22, Trackpad:

Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:22.0) Gecko/20100101 Firefox/22.0
wheel: deltaY=1, deltaMode=0

MacOS, FF 22, Generic Scroll Mouse:

Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:22.0) Gecko/20100101 Firefox/22.0
wheel: deltaY=0.100006103515625, deltaMode=1

MacOS, FF 22, Mighty Mouse:

Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:22.0) Gecko/20100101 Firefox/22.0
wheel: deltaY=0, deltaMode=0
wheel: deltaY=1, deltaMode=0
wheel: deltaY=6, deltaMode=0
wheel: deltaY=9, deltaMode=0

Ubuntu, Chromium, Trackpad (same with scroll mouse):

Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.22 (KHTML, like Gecko) Ubuntu Chromium/25.0.1364.160 Chrome/25.0.1364.160 Safari/537.22
mousewheel: wheelDelta=-120, detail=0

MacOS, Chrome, Trackpad:

Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.116 Safari/537.36
mousewheel: wheelDelta=3, detail=0

MacOS, Safari, Mouse:

mousewheel: wheelDelta=12, detail=0

MacOS, Chrome, Generic Scroll Mouse:

Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.116 Safari/537.36
mousewheel: wheelDelta=120, detail=0

MacOS, Chrome, Mighty Mouse:

Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.116 Safari/537.36
mousewheel: wheelDelta=3, detail=0

[klimashkin]

Firefox rocks! Different deltaY in different OS. Maybe it's issue for Mozilla tracker?

[jfirebaugh]

@klimashkin trackpad or mouse?

[klimashkin]

Mouse, updated

[klimashkin]

Update. Received such results on Windows 7, FF22:

Mousewheel deltaY: 3 - 24 (step 3)
Trackpad deltaY: 0.1 - 11 (step 0.05)
(And always deltaMode=1)

[ajbeaven]

This is hitting us too. Windows 7, FF 21, Mouse.

Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20100101 Firefox/21.0
wheel: deltaY=3, deltaMode=1

[mourner]

@jfirebaugh should we just revert the wheel change generally for now but add a preventDefault on it just for fixing the FF scrolling issue?

[mourner]

Or maybe we should make another JSFiddle — gathering data for only FF but for all events (wheel, DOMMouseScroll and MozMousePixelScroll) at the same time.

[jfirebaugh]

should we just revert the wheel change generally for now but add a preventDefault on it just for fixing the FF scrolling issue?

If you preventDefault on wheel you don't get any DOMMouseScroll events, so that won't work.

So far it's looking like we'll need to divide deltaY by 3 when deltaMode=1. That will result in an even smaller value on MacOS, FF 22, Generic Scroll Mouse, but since the ceiling is taken anyway it shouldn't matter.

[mourner]

Sounds good to me. It won't affect other browsers right?

[jfirebaugh]

It won't affect other browsers right?

Not yet anyway. If other browsers start implementing "wheel" event that could change.

Here's a fiddle that records all Firefox wheel-related data: http://jsfiddle.net/ydVda/1/

One thing I notice is that with a Mac trackpad, several "wheel" events can be dispatched before a DOMMouseScroll is dispatched. This agrees with the documentation: "A vertical DOMMouseScroll event in both event group if accumulated deltaY of consecutive wheel events become larger than 1.0 or less than -1.0". This implies several things:

• With Leaflet 0.5, small trackpad movements didn't generate a zoom, while with 0.6 they do.
• The original bug with zoom events also scrolling the page is only reproducible when there are several "wheel" events before accumulating a DOMMouseScroll event. This may only be possible with a trackpad -- in my tests I always see a one-to-one correspondence between wheel and DOMMouseScroll events with wheel mice.

[mindplay-dk]

This still affects me in Firefox 26.0 under Windows 8 with an IntelliMouse Explorer 3.0 - the Leaflet on the front page of the website jumps two or three zoom levels when using the wheel.

Event log for a single up and down motion:

Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/31.0.1650.63 Safari/537.36
wheel: deltaY=-133.3333282470703, deltaMode=0
wheel: deltaY=133.3333282470703, deltaMode=0

Man, mouse-wheel events are just totally botched across browsers, sheeeesh...

[mourner]

@mindplay-dk yeah, programming for scroll wheels and trackpads is such a pain... One more related issue: #2154 I'm going to completely rewrite the way zoom animations and scroll wheels work, stay tuned for updates in master in the following weeks.

[michaelzed]

I find the otherwise excellent Magic Mouse scrolling very frustrating in Leaflet (e.g., on OpenStreetMap.org in Safari). Just trying to pan around the map causes many unintentional zooms in or out. Zooming often overshoots. Is this covered here, or should I open another bug?

[ganeshx]

Has this issue been fixed? The zoom in/out is too sensitive

[mourner]

@ganeshx can you try the master version?

[CramericaIndustries]

Sorry but that bug is back. Tested with Fire Fox 54.0.1 and Leaflet 1.1.0. Chrome works fine (v59.0.3071.115).
Example map: http://leafletjs.com/

[perliedman]

@CramericaIndustries please open a new issue if you believe this is a bug in the current Leaflet release, it's highly unlikely it's related to this four year old issue.

[CramericaIndustries]

Root of the problem was that the mousewheel.with_alt.delta_multiplier_y parameter was set to 500 (default 100) in about:config.
However scrolling on normal html-sites went much slower then, but was able to speed it up again by setting mousewheel.acceleration.start to 1. This setting had no effect on Leaflet.

Maybe this helps other poeple having the same issue.