532484 - Key Esc force-pauses SMIL animations

Status: RESOLVED WORKSFORME

(Core :: SVG, defect)

Description

[Marek Raida]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.3a1pre) Gecko/20091202 Minefield/3.7a1pre
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.3a1pre) Gecko/20091202 Minefield/3.7a1pre

Given URL is picked up randomly - it affects all SMIL animations... 
Key Esc works as Pause for SMIL animations, unless is its behavior prevented by script via evt.preventDefault()
However, this is uncommon behavior I'm unable to find in any other SMIL supporting browser, so I believe it is unwanted.

Reproducible: Always

Steps to Reproduce:
1. Open page with SVG SMIL animation without scripting (to be sure there is no preventDefault method in use)
2. Press key Esc (Escape)
3. All animations stop and it is not possible to resume them without reloading page 
Actual Results:  
Animation is paused

Expected Results:  
Animation should be unaffected

It would be great to support some context menu or some other user friendly interface to allow pause/resume of SVG SMIL animations...

Comment 1

[Matthias Versen [:Matti]]

I think this is by design, ESC should stop animations on the page like animated gifs but not plugins (not under pour control)

Comment 2

[Daniel Holbert [:dholbert]]

Yes, this behavior is by design, though I guess this does sorta break SVG documents/games/etc that use the "Esc" key. (Unless they use the "evt.preventDefault()" workaround mentioned in comment 0).

For example, this game written by Marek uses "esc" to jump back to its menu:
   http://svg.kvalitne.cz/cavern/083/cavern.svg
(I think it uses "evt.preventDefault()" to avoid this problem, though.)

Perhaps we should reconsider this decision?

Comment 3

[Jonathan Watt [:jwatt]]

I'm not mad about the idea of pausing SMIL animation via the ESC key, FWIW. I'd rather have Pause/Resume Animation context menu items added dynamically when animation is active. Or something like that.

Comment 4

[Brian Birtles (:birtles)]

I think the bits of code in question are:

http://mxr.mozilla.org/mozilla-central/source/layout/base/nsPresContext.cpp#1112
(called here: http://mxr.mozilla.org/mozilla-central/source/layout/base/nsPresContext.cpp#1168)
http://mxr.mozilla.org/mozilla-central/source/content/base/src/nsDocument.cpp#5339

I don't mind the current behaviour but I guess it should be a UI person who decides.

I wonder if a possible solution would be to have ESC only pause SVG images sourced via an <img> element (which I don't think we support yet right?).

The reason is that it seems to me you probably DON'T want the ESC behaviour when you're building web *applications* but if you're simply making web *pages* which have a few linked images then it would be nice to turn off annoying animations like you can with animated GIFs. One use case that comes to mind is animated SVGravatars(TM).*

* Actually I haven't registered that tradmark, yet.

Comment 5

[Daniel Holbert [:dholbert]]

See also bug 499591.

Comment 6

[Robert Longson [:longsonr]]

Esc no longer pauses SMIL. I think ESC is ignored now once a document has loaded.