Tutorials · Sound and Music · Chapter 6

The mix

Four interface sounds

1. Download Interface Sounds from its page below. Copy the four files into your project’s audio folder, each from where the list says, and press Refresh in the Assets panel.
2. Click each in Assets and press Play in Details: each is a tenth of a second or less.

The crypt’s mix

1. With crypt.ron open, select Crypt, the root. Press + Add node and choose Audio Mix. Rename the new node mix.
2. In its AudioMixComponent, open Effects, then Master. Press the + beside Slots: a slot, numbered 1, as a slot comes, a Gain of 0 dB with Enabled ticked, which changes nothing. Open it, set its Effect to Compressor, and set Threshold to -1, Ratio to 20, Attack to 0 and Release to 0.1.
3. Open Music and press + beside its Slots. Leave its Effect on Gain, and set its Gain to -4.
4. Open Sfx and press + beside its Slots. Set its Effect to Compressor, with Threshold -15, Ratio 4, Attack 0.001 and Release 0.15.
5. Press + beside Sfx’s Slots again: a second slot, a Gain of 0 dB as a slot comes. Set its Effect to Panner, with Pan 0.5 and Width 0.5, and untick its Enabled.
6. Press Ctrl+S.

The Audio Mix’s Effects

A chain of effects for each bus: Master, Music and Sfx. A sound passes through its own bus’s chain, first slot to last, and then through Master’s. An empty chain changes nothing, as each bus’s is until you add a slot. The mix’s other three lists, Snapshots, Ducking and Sends, are chapters 7 and 8.

The Master chain, and its Slots

What every sound passes through last, whatever its bus. Its Slots are its effects, first to last: here one, the safety. Each slot is numbered by its place; the arrows on its row move it, and the bin removes it.

The Music chain, and its Slots

What the music passes through: the room’s own track, the alcove’s calm, any music the crypt plays. Here one slot, the Gain that sets the music under the room.

The Sfx chain, and its Slots

What every sound that is not music passes through: the torches, the steps, the doors, the box. Here two slots, the Compressor and, after it, the Panner.

A Master slot’s Effect and Enabled

Its Effect is which effect the slot applies, chosen from nine: LowPass, HighPass, BandPass, Delay, Distortion, Gain, Compressor, Reverb and Panner. Choosing one shows that effect’s own fields under it. Enabled switches it on; unticked, the slot is still there with its fields, and passes the sound as it came. Master’s one slot is a Compressor, ticked.

A Music slot’s Effect and Enabled

The same two on Music’s chain: its one slot is a Gain, ticked. Chapter 9 adds a LowPass after it, unticked, for the pause.

An Sfx slot’s Effect and Enabled

The same two on Sfx’s chain: a Compressor, ticked, and a Panner, unticked. An unticked slot is how an effect is kept to try again, its fields as you left them: tick it, listen, untick it. Chapter 7 adds a Reverb and a Delay here, each unticked, which a room switches on.

The Compressor, and its Threshold

A Compressor pulls down whatever goes over its Threshold, so the loud moments come down and the quiet ones are left. Threshold is where it starts, in decibels under full scale, 0 dB being the loudest a game can play: Master’s at -1, Sfx’s at -15.

The Compressor’s Ratio

How much of each decibel over the Threshold comes out, the other way up: at 4, four decibels over come out as one; at 20, twenty as one, which is all but a wall. From 1, which does nothing, to 100.

The Compressor’s Attack and Release

How fast it clamps down once the sound goes over, and how fast it lets go once it falls back, in seconds. Master’s Attack of 0 clamps on the very sample that goes over; Sfx’s 0.001 is a thousandth of a second. Each Release is a tenth of a second or so, so the sound comes back up between hits.

The Gain’s Gain

A flat change of level, in decibels: -4 takes four off whatever passes, +6 doubles it. From -96 to 24. A new slot is a Gain of 0, which changes nothing. It is the mix’s, not the player’s: the options screen’s volumes, below, sit after it.

The Panner’s Pan and Width

Where a whole bus sits between your ears, and how wide it is. Pan goes from -1, all left, through 0 to 1, all right; at 0.5 the left ear is halved. Width is 0 for both ears the same, 1 as recorded and 2 doubled; at 0.5 the difference between the ears is halved. It moves every sound on the bus at once, where a source’s own Pan moves one.

The Compressor, heard and seen

1. Press F5 and click the Sound tab.
2. Walk the knight to the bridge room’s east bank, below the cave’s door, and then up into the doorway: the door creaks open.
3. Press F5 to stop. Untick the Compressor’s Enabled on Sfx, press F5 and do the same. Then tick it again, and press Ctrl+S.

A meter’s bar

How loud the bus is now, over the last moment of sound, about a fiftieth of a second, with its reading beside it in decibels. It is the bar that shows a Compressor at work: it is how loud the sound is held, and the Compressor holds the loud part down.

A meter’s peak tick

The loudest single moment of the last second, held there for that second, then let fall. It says how near the bus came to 0 dB, where a game clips, which is what Master’s safety watches for.

The title’s own mix

1. Open title.ron. Select Title, its root, press + Add node and choose Audio Mix. Rename it mix.
2. On Master, press + beside Slots and make it a Compressor: Threshold -1, Ratio 20, Attack 0, Release 0.1. Leave Music and Sfx with no slots.
3. Press Ctrl+S.

Three sliders

1. In Assets, click Assets in the path bar, so the script is written at the project’s top, then click Create, choose New script, type master_volume and press Enter. In the Code tab, replace everything in master_volume.rgs with the script below, and press Ctrl+S.
2. Do the same for music_volume and sfx_volume.
3. In title.ron, select master, under options_panel’s master_row. Press Add component and choose MasterVolume. Give music MusicVolume and sfx SfxVolume the same way. Press Ctrl+S.

/// The Master slider: everything the game plays, at once. It opens where the
/// saved volume is, and sets the game's Master to it; each move the player
/// makes sets Master's volume, saves it, and ticks. The volume is the game's,
/// not the title's: it holds in the crypt, and the next time the game opens.
component MasterVolume {
    fn on_create() {
        // 0.8 until the player has chosen one, so there is room to turn it
        // up. Writing the slider moves it and presses nothing, so it opens on
        // the saved volume without a tick.
        let level = saved_number("master_volume", 0.8);
        set_number("SliderComponent", "value", level);
        set_master_volume(level);
    }

    fn loop() {
        // A drag, a click on its bar, or A and D, or the Left and Right
        // arrows, while it holds the focus moves it, and presses master on
        // that step; amount() answers where it now is.
        if pressed("master") {
            let level = amount("master");
            set_master_volume(level);
            save_number("master_volume", level);
            play_sound("tick");
        }
    }
}

/// The Music slider: the Music bus, the title's music and the crypt's. It
/// opens where the saved volume is, and sets the game's music to it; each move
/// the player makes sets the Music bus's volume, saves it, and ticks. The
/// volume is the game's, not the title's: it holds in the crypt, and the next
/// time the game opens.
component MusicVolume {
    fn on_create() {
        // 0.8 until the player has chosen one, so there is room to turn it
        // up. Writing the slider moves it and presses nothing, so it opens on
        // the saved volume without a tick.
        let level = saved_number("music_volume", 0.8);
        set_number("SliderComponent", "value", level);
        set_music_volume(level);
    }

    fn loop() {
        // A drag, a click on its bar, or A and D, or the Left and Right
        // arrows, while it holds the focus moves it, and presses music on
        // that step; amount() answers where it now is.
        if pressed("music") {
            let level = amount("music");
            set_music_volume(level);
            save_number("music_volume", level);
            play_sound("tick");
        }
    }
}

/// The Sfx slider: the Sfx bus, every sound that is not music, these menus'
/// clicks included. It opens where the saved volume is, and sets the game's
/// Sfx to it; each move the player makes sets the Sfx bus's volume, saves it,
/// and ticks, on Sfx too, so the tick is heard at the volume it sets. The
/// volume is the game's, not the title's: it holds in the crypt, and the next
/// time the game opens.
component SfxVolume {
    fn on_create() {
        // 0.8 until the player has chosen one, so there is room to turn it
        // up. Writing the slider moves it and presses nothing, so it opens on
        // the saved volume without a tick.
        let level = saved_number("sfx_volume", 0.8);
        set_number("SliderComponent", "value", level);
        set_sfx_volume(level);
    }

    fn loop() {
        // A drag, a click on its bar, or A and D, or the Left and Right
        // arrows, while it holds the focus moves it, and presses sfx on that
        // step; amount() answers where it now is.
        if pressed("sfx") {
            let level = amount("sfx");
            set_sfx_volume(level);
            save_number("sfx_volume", level);
            play_sound("tick");
        }
    }
}

set_master_volume, set_music_volume and set_sfx_volume

Set the game’s volume for one bus, from 0, silent, to 1, full. Each is the bus’s fader, after its chain, and it is the game’s, not a room’s: it holds through a change of scene, until a script sets it again. A volume and a mix multiply, and neither reads the other back.

saved_number

Reads a number saved under a name, as it was when the step began, or the number after the name if nothing was ever saved: here 0.8, so a slider opens with room to turn it up.

save_number

Saves a number under a name, to the game’s own saved file, where it lasts from one opening of the game to the next. It lands at the end of the step.

set_number

Writes a number onto another component of the script’s node: here the slider’s Value. Writing it moves the slider and presses nothing, so a slider opens on its saved volume without a tick.

amount

How far a slider for an action stands, in its own range: here from 0 to 1, in steps of a tenth. Asked on the step its action is pressed, it is where the player has just moved it.

pressed

Whether an action went down on this step. A slider presses its action on every step it moves: a drag, a click on its bar, or A and D while it holds the focus.

Clicks, blips and ticks

1. In title.ron, select title_frame. Press Add component and choose AudioSourceComponent. Leave Clip empty, Bus on Sfx and Volume at 1. In Spatial, untick Positional. Add a trigger click, its Clip click_001.ogg, and a trigger select, its Clip select_001.ogg.
2. Give options_panel the same, with the triggers back, back_001.ogg, and select, select_001.ogg.
3. Give each of master, music and sfx the same, with one trigger tick, tick_001.ogg.
4. Replace everything in title_menu.rgs and in options.rgs with the scripts below. Press Ctrl+S.

/// The title's menu: Play opens the crypt, and Options swaps this menu for the
/// options panel, whose Back swaps it back. A press clicks, and a move of the
/// focus round the menu blips: the triggers of this node's Audio Source.
component TitleMenu {
    /// Whether the menu is showing, so that it blips for its own focus moves
    /// and not for the options panel's.
    #[hidden]
    shown: bool = true,

    fn loop() {
        // A click on Play or Options, or Enter or Space while it holds the
        // focus, presses its action on the game's next step. A sound asked
        // for on the step that changes scene plays on after it.
        if pressed("play") {
            play_sound("click");
            change_scene("crypt");
        }
        if pressed("options") {
            play_sound("click");
            hide();
            shown = false;
        }
        // A click on the options panel's Back, Enter or Space while it holds
        // the focus, or Escape through its Shortcut.
        if pressed("back") {
            show();
            shown = true;
        }
        // W or S, or the Up and Down arrows, move the focus round the menu.
        if shown && (pressed("ui_up") || pressed("ui_down")) {
            play_sound("select");
        }
    }
}

/// The options panel: hidden as the title opens, shown by the menu's Options,
/// and hidden again by its own Back, which clicks the way back. A move of the
/// focus round its sliders and Back blips. Each slider sets its own bus, by a
/// script of its own.
component Options {
    /// Whether the panel is showing, so that it blips for its own focus moves
    /// and not for the menu's.
    #[hidden]
    shown: bool = false,

    fn loop() {
        // A click on Options, or Enter or Space while it holds the focus.
        if pressed("options") {
            show();
            shown = true;
        }
        // A click on Back, Enter or Space while it holds the focus, or Escape
        // through its Shortcut.
        if pressed("back") {
            play_sound("back");
            hide();
            shown = false;
        }
        // W or S, or the Up and Down arrows, move the focus round the panel.
        if shown && (pressed("ui_up") || pressed("ui_down")) {
            play_sound("select");
        }
    }
}

Who decides what you hear

The mix

Check it works