Sound, music, and images

A story declares its media assets once, by name, and then plays or shows them from any statement body. The files live under the project's assets/ directory and ship with the browser build; a client that cannot play a kind of media simply ignores the cue, and the when client has … condition lets the story say something else instead.

Declaring assets

define sound night-wind from "audio/night-wind.wav"
define sound boiler-thump from "audio/boiler-thump.wav"
define music dawn-theme from "audio/dawn-theme.wav"
define image folly-photograph from "images/folly-photograph.png"

Three kinds: a sound is a one-shot cue, music is a track, an image is a picture. The path is relative to assets/. Every play or show names one of these declarations, and the compiler checks the name and the kind — a play music of a define sound is a diagnostic, and a misspelled asset carries a nearest-match suggestion.

Sounds in the world

A sound is heard in the world as well as on the player's speakers. play sound plays the file, if it has one, and also makes the sound in the room of the block it is written in. A listener, which can be a person or a thing, reacts with after hearing the <sound> in its own block, in the same turn, if the sound carries far enough to reach it. A sound with no file is heard in the world and played on no speaker.

define sound depot-klaxon

create the call button
  a thing, scenery, pushable
  in the Loading Dock

  after the player pushing
    play sound depot-klaxon
  end after

create the loader robot
  a person, listener
  in the Loading Dock

  after hearing the depot-klaxon
    move the mail sack to the Loading Dock
    phrase robot-fetches-sack
  end after

How far a sound carries, through open exits and past walls, is the platform's to work out; a story only says who listens. hearing takes no on form, since a sound cannot be refused after it was made. A play sound written when client has sound is a sound the world hears only on clients that play audio, so leave that condition off a sound something in the story must hear.

Playing and showing

create the primer plunger
  aka plunger
  a thing, scenery
  in the Boiler Shed

  A stiff brass plunger on the boiler's flank.

  after the player pushing
    play sound boiler-thump when client has sound
    phrase primer-thumps
  end after

Every one of these takes the ordinary when <condition> suffix, so a cue can wait on a state or a client capability:

create the Iron Gates
  a room

  Wrought-iron gates stand open on one hinge apiece.

  after the player entering while the player has the deed
    play music dawn-theme when client has music
    win fernhill-saved
  end after

client has sound, client has music, and client has images are true when the client running the story can play that kind of media. A cue without the guard is harmless on a client that cannot honour it — the guard is for the story that wants to say something different when the music cannot play.

Ambients follow the player

An ambient is a looping bed the rooms of a region can share. Start it on arrival and stop it on leaving, and the wind follows the player across the grounds and stops at the door:

create the Grounds
  a region

  after the player entering
    play ambient night-wind when client has sound
  end after

  after the player leaving
    stop ambient when client has sound
  end after

create the Gravel Drive
  a room
  in the Grounds

  Gravel crunches underfoot.

create the Fountain Court
  a room
  in the Grounds

  A dry fountain stands in the middle of the court.

The Fernhill walkthrough shows all three kinds wired into a complete story and played in the browser build.