995576 - No sound with "Paris Metro Simulator" HTML5 game

Status: RESOLVED FIXED

(Web Compatibility :: Site Reports, defect)

Description

[Mathieu Marquer]

User Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:31.0) Gecko/20100101 Firefox/31.0 (Beta/Release)
Build ID: 20140412030202

Steps to reproduce:

Go on http://parismetrosimulator.appspot.com/
Select any line
Press the red button and play the game


Actual results:

Game runs with no sound


Expected results:

Game should run with sound, as it does for example with Google Chrome.

No sound with either Windows 7 or Ubuntu Linux 14.04 beta

Comment 1

[Michael]

Confirmed on Windows 8.

Comment 2

[Chris Pearce [:cpearce (Not reading bugmail)]]

This page uses WebAudio, so this is either a bug in our WebAudio or a compat issue.

Comment 3

[Paul Adenot (:padenot)]

Line 1058 of file [1], we see:

>  self_0.buffer_0 = context.createBuffer(request.response, false);

This is using the super old and deprecated synchronous version of `createBuffer` on encoded data, that has been removed from the spec, because long blocking calls on the main thread must be avoided in the web platform.

This game is using the PlayN framework. It's not obvious to me if this is fixed in the current version of the framework, I tried digging in the java to html transpiler, but it's pretty convoluted.

In any case, this is now an evangelization bug. This game will stop working in Chrome in the near future, as they stated they will remove deprecated APIs in the future. They are currently in a transition period where they support the old and the new API, but it will change.

If someone contacts the author, [2] can be useful, especially the paragraph on the synchronous version of `createBuffer` [3] and how to update the code to be spec-compliant and future proof.

[1]: http://parismetrosimulator.appspot.com/metro/E95890044132A49334DB9EEA63F2E63D.cache.html
[2]: https://developer.mozilla.org/en-US/docs/Web_Audio_API/Porting_webkitAudioContext_code_to_standards_based_AudioContext
[3]: https://developer.mozilla.org/en-US/docs/Web_Audio_API/Porting_webkitAudioContext_code_to_standards_based_AudioContext#Removal_of_the_synchronous_AudioContext.createBuffer_function

Comment 4

[Mathieu Marquer]

I'll contact them, thanks for the investigation :)

Comment 5

[Fred Sauer]

I've uploaded an updated gwt-voices jar to https://code.google.com/p/gwt-voices/issues/detail?id=35

Let me know if it works alright. If so, I'll put this jar out as a new gwt-voices release which PlayN can then depend on

Comment 6

[Fred Sauer]

I've pushed gwt-voices-3.3.1 to maven central. Please give it a try with PlayN.
(Note Maven Central releases on Sunday's only, so you may have to wait till next week.)

Comment 7

[fredericpaulin]

Hi,
Sorry for the late comment.

I tried and the result is the following:
Previously, with playn-1.8.5 on Windows 7 with old Mozilla 27.0 and IE 9.0 I used to have sound, but not with the latest Mozilla version (I tried on Mac)
You can try:
http://401.latest.parismetrosimulator.appspot.com

Now, with playn 1.9-SNAPSHOT and gwt-voices-3.3.1 it now works for latest Mozilla but no longer for
old Mozilla 27.0 and IE 9.
You can try :
http://41.latest.parismetrosimulator.appspot.com

Comment 8

[Karl Dubost💡 :karlcow]

That's normal. It's not working for the old Mozilla. I propose we close it as FIXED.
Thanks a lot Fred.