Add "Mute Game" toggle in Game view

[Meorge]

This should close godotengine/godot-proposals#1066.

It adds a button to the Game view's toolbar that disables all audio output from the game when toggled off.

Godot.Mute.Audio.Button.mp4

Things to consider:

• The code was structured to mimic the camera override implementation. It seems to be working well, but I'm feeling a little iffy about having separate audio_enabled members for EditorDebuggerNode and ScriptEditorDebugger, rather than a single source of truth for whether or not audio is enabled.
• Currently, it defaults to being enabled, and stays in sync with the AudioServer simply by being the only object to modify it. We may want to add a signal or something to the AudioServer that emits whenever the mute variable is changed, so that the button's toggled state can update appropriately if mute is changed from elsewhere.
• The current icon may be a bit confusing. It could be good to create a crossed-out version of the AudioStreamPlayer icon to indicate that sound is muted.
• Similarly, the meaning of the button is a bit mixed. It's technically an "enable audio" button (as in, when toggled on, audio plays). The addition to AudioServer, on the other hand, is a mute variable (when true, audio doesn't play.) I did this to keep it consistent with set_bus_mute, but I'm wondering if one direction (true = mute, or true = audible) should be chosen for this whole flow instead.

[YeldhamDev]

The button should disable audio when toggled on, since the audio being enabled is the default state. Having buttons be in a pressed state as the default unnecessarily draws attention to them.

[Meorge]

It sounds like Unity's equivalent of this is also a "mute audio" button and not an "enable audio" button. Between that (i.e., standardizing) and the point you brought up about muted audio not being the default behavior, I agree that it'd make more sense for the button's pressed state to make the audio not play.

It also occurred to me that this should perhaps be made into either a project-level or editor-level setting, so that it is kept on closing and re-opening the editor. At present it always defaults to not muting, which I could see being annoying. I'll look more into how to save its state.

[tetrapod00]

It also occurred to me that this should perhaps be made into either a project-level or editor-level setting, so that it is kept on closing and re-opening the editor. At present it always defaults to not muting, which I could see being annoying. I'll look more into how to save its state.

I'm not an expert in the norms for editor code but I believe this is a good use case for using project metadata. The editor can remember the toggled state of the mute button, across multiple tests of the game and multiple editor sessions, without the need for a project or editor setting that the user has to go menus to change.

[Calinou]

• The current icon may be a bit confusing. It could be good to create a crossed-out version of the AudioStreamPlayer icon to indicate that sound is muted.

Here you go 🙂

mute_audio_icons.zip

MuteAudio2 is my favorite personally, but MuteAudio3 may look better at 16x16.

[Meorge]

Thank you very much for the icons! 😄

Currently, I have it set up so that it displays the regular AudioStreamPlayer icon when not enabled to indicate that audio will play, and then switches to the muted icon when it is toggled on:

Godot.Mute.Audio.Button.with.Icons.mp4

The icons themselves look great, but unfortunately the blue tint that Godot applies makes it a bit hard to read the red strikethrough, in my opinion... What are your thoughts?

[tetrapod00]

IMO the strikethrough does not need to be red; it can be whatever the color of the surrounding icon is. The toggled style and difference in icon is already sufficient to distinguish the states.

[Meorge]

I suppose we can see what others think as well, but I personally like the red "highlight" of the strikethrough - it draws my attention to the fact that this isn't an ordinary audio icon, that something is very different about its current state.

Perhaps Godot's icon support already has something like this, and/or perhaps it doesn't and it would be considered unnecessary or infeasible. But it would be neat if certain portions of an SVG could be marked as "don't recolor for the selected variation", so that in spots like these, the highlighted parts would retain their contrast against the rest of the icon.

[Meorge]

There's currently a bug where, if the "mute audio" toggle is activated before the game is run, you can hear the game for a split second before the mute takes effect. I have a feeling this may have to do with the messaging system that it uses to send events to the game taking a frame to process, and if so I'm not entirely sure how this would be gotten around 😅

[Meorge]

Following Calinou's suggestions in the contributor chat, I changed the way the button works to match the Skip Breakpoints button in the debugger. This looks a lot better to me!

Godot.Mute.Audio.Button.with.Icons.No.Tint.Adaptive.Tooltips.mp4

The bright red strikethrough feels much more prominent, and indicates that the game is currently muted to me.

[Calinou]

Tested locally, it works as expected (including if you stop the project and run it again with game audio muted).

Note that the option doesn't persist across editor restarts (only game restarts), which is good since it avoids accidentally forgetting about it and wondering why the game doesn't play any audio.

[Meorge]

Thanks for reviewing and approving! 😄

it works as expected (including if you stop the project and run it again with game audio muted).

I'm glad this is working for you, but on my end when I run it with game audio muted, I can hear it for a split second. Is it completely silent for you the whole time?

Godot.Mute.Audio.Button.Gives.Frame.of.Audio.At.Beginning.mp4

Note that the option doesn't persist across editor restarts (only game restarts), which is good since it avoids accidentally forgetting about it and wondering why the game doesn't play any audio.

I agree that forgetting about it, then being confused why no audio is playing is a valid concern - I think that may have happened to me in the past with Unity, actually. Given that, perhaps it makes sense to leave the behavior that way for now, and consider possibilities for saving in a follow-up proposal/discussion. I could see there being cases, though, where someone may want to keep the setting off and not need to disable it every time they start the editor. Perhaps we could do something like have a toast notification appear on project startup warning the user that the mute setting is enabled?