audio

Documentation

Overview

Package audio provides access to 3D sound capability. The expected usage is to initialize the audio system and load sound data. Then play sounds that are close enough to the sound listener to be audible.

Package audio is provided as part of the vu (virtual universe) 3D engine.

Index

• type Audio
  • func New() Audio
• type Data
  • func (d *Data) Set(channels, sampleBits uint16, frequency, dataSize uint32, data []byte)
• type NoAudio
  • func (na *NoAudio) BindSound(sound, buff *uint64, d *Data) error
  • func (na *NoAudio) Dispose()
  • func (na *NoAudio) Init() error
  • func (na *NoAudio) PlaceListener(x, y, z float64)
  • func (na *NoAudio) PlaySound(sound uint64, x, y, z float64)
  • func (na *NoAudio) ReleaseSound(sound uint64)
  • func (na *NoAudio) SetGain(gain float64)

Types

type Audio

type Audio interface {
	Init() error          // Get the audio layer up and running.
	Dispose()             // Closes and cleans up the audio layer.
	SetGain(gain float64) // Volume control: valid values are 0->1.

	// BindSound copies the sound data to the sound card and returns
	// references that can be used to dispose of the sound with ReleaseSound.
	//     sound : updated reference to the bound sound.
	//     buff  : updated reference to the sound data buffer.
	//     d     : sound data bytes and settings to be bound.
	BindSound(sound, buff *uint64, d *Data) error
	ReleaseSound(sound uint64)

	// Control sounds by setting the x,y,z locations for a listener
	// and the played sounds. While there is only ever one listener,
	// there can be many sounds.
	PlaceListener(x, y, z float64)           // Only ever one listener.
	PlaySound(sound uint64, x, y, z float64) // Play the bound sound.
}

Audio interacts with the underlying audio layer which in turn interfaces to the sound drivers and hardware. Audio must be initialized once before sounds can be bound and played.

func New

func New() Audio

New provides a default audio implementation.

type Data

type Data struct {
	Name       string // Unique sound name.
	AudioData  []byte // The raw audio data.
	Channels   uint16 // Number of audio channels.
	SampleBits uint16 // 8 bits = 8, 16 bits = 16, etc.
	Frequency  uint32 // 8000, 44100, etc.
	DataSize   uint32 // Audio data size: total file size minus header size.
}

Data is a shared audio resource that is used to load sound data onto a sound card using BindSound().

func (*Data) Set

func (d *Data) Set(channels, sampleBits uint16, frequency, dataSize uint32, data []byte)

Set is a convenience method that populates sound data with the given information. It attempts to reuse the existing sound buffer.

type NoAudio

type NoAudio struct{}

NoAudio can be used to mock out audio when audio initialization fails.

func (*NoAudio) BindSound

func (na *NoAudio) BindSound(sound, buff *uint64, d *Data) error

BindSound is mocked method for Audio interface.

func (*NoAudio) Dispose

func (na *NoAudio) Dispose()

Dispose is mocked method for Audio interface.

func (*NoAudio) Init

func (na *NoAudio) Init() error

Init is mocked method for Audio interface.

func (*NoAudio) PlaceListener

func (na *NoAudio) PlaceListener(x, y, z float64)

PlaceListener is mocked method for Audio interface.

func (*NoAudio) PlaySound

func (na *NoAudio) PlaySound(sound uint64, x, y, z float64)

PlaySound is mocked method for Audio interface.

func (*NoAudio) ReleaseSound

func (na *NoAudio) ReleaseSound(sound uint64)

ReleaseSound is mocked method for Audio interface.

func (*NoAudio) SetGain

func (na *NoAudio) SetGain(gain float64)

SetGain is mocked method for Audio interface.