class EE::Audio::Music¶
Overview¶
Streamed music played from an audio file. More…
#include <music.hpp> class Music: public EE::Audio::SoundStream { public: // typedefs typedef Span<Time> TimeSpan; // structs template <typename T> struct Span; // construction ~Music(); // methods static Music* New(); bool openFromFile(const std::string& filename); bool openFromMemory(const void* data, std::size_t sizeInBytes); bool openFromStream(IOStream& stream); bool openFromPack(Pack* pack, const std::string& filePackPath); Time getDuration() const; TimeSpan getLoopPoints() const; void setLoopPoints(TimeSpan timePoints); };
Inherited Members¶
public: // enums enum Status; // structs struct Chunk; // methods void setPitch(float pitch); void setVolume(float volume); void setPosition(float x, float y, float z); void setPosition(const Vector3f& position); void setRelativeToListener(bool relative); void setMinDistance(float distance); void setAttenuation(float attenuation); float getPitch() const; float getVolume() const; Vector3f getPosition() const; bool isRelativeToListener() const; float getMinDistance() const; float getAttenuation() const; SoundSource& operator=(const SoundSource& right); virtual void play() = 0; virtual void pause() = 0; virtual void stop() = 0; virtual Status getStatus() const; virtual void play(); virtual void pause(); virtual void stop(); unsigned int getChannelCount() const; unsigned int getSampleRate() const; virtual Status getStatus() const; void setPlayingOffset(Time timeOffset); Time getPlayingOffset() const; void setLoop(bool loop); bool getLoop() const;
Detailed Documentation¶
Streamed music played from an audio file.
Musics are sounds that are streamed rather than completely loaded in memory. This is especially useful for compressed musics that usually take hundreds of MB when they are uncompressed: by streaming it instead of loading it entirely, you avoid saturating the memory and have almost no loading delay. This implies that the underlying resource (file, stream or memory buffer) must remain valid for the lifetime of the Music object.
Apart from that, a Music has almost the same features as the SoundBuffer / Sound pair: you can play/pause/stop it, request its parameters (channels, sample rate), change the way it is played (pitch, volume, 3D position, …), etc.
As a sound stream, a music is played in its own thread in order not to block the rest of the program. This means that you can leave the music alone after calling play(), it will manage itself very well.
Usage example:
// Declare a new music Music music; // Open it from an audio file if (!music.openFromFile("music.ogg")) { // error... } // Change some parameters music.setPosition(0, 1, 10); // change its 3D position music.setPitch(2); // increase the pitch music.setVolume(50); // reduce the volume music.setLoop(true); // make it loop // Play it music.play();
See also:
Methods¶
bool openFromFile(const std::string& filename)
Open a music from an audio file.
This function doesn’t start playing the music (call play() to do so). See the documentation of InputSoundFile for the list of supported formats.
Warning
Since the music is not loaded at once but rather streamed continuously, the file must remain accessible until the Music object loads a new music or is destroyed.
Parameters:
filename |
Path of the music file to open |
Returns:
True if loading succeeded, false if it failed
See also:
openFromMemory, openFromStream
bool openFromMemory(const void* data, std::size_t sizeInBytes)
Open a music from an audio file in memory.
This function doesn’t start playing the music (call play() to do so). See the documentation of InputSoundFile for the list of supported formats.
Warning
Since the music is not loaded at once but rather streamed continuously, the data buffer must remain accessible until the Music object loads a new music or is destroyed. That is, you can’t deallocate the buffer right after calling this function.
Parameters:
data |
Pointer to the file data in memory |
sizeInBytes |
Size of the data to load, in bytes |
Returns:
True if loading succeeded, false if it failed
See also:
bool openFromStream(IOStream& stream)
Open a music from an audio file in a custom stream.
This function doesn’t start playing the music (call play() to do so). See the documentation of InputSoundFile for the list of supported formats.
Warning
Since the music is not loaded at once but rather streamed continuously, the stream must remain accessible until the Music object loads a new music or is destroyed.
Parameters:
stream |
Source stream to read from |
Returns:
True if loading succeeded, false if it failed
See also:
Time getDuration() const
Get the total duration of the music.
Returns:
Music duration
TimeSpan getLoopPoints() const
Get the positions of the of the sound’s looping sequence.
Warning
Since setLoopPoints() performs some adjustments on the provided values and rounds them to internal samples, a call to getLoopPoints() is not guaranteed to return the same times passed into a previous call to setLoopPoints(). However, it is guaranteed to return times that will map to the valid internal samples of this Music if they are later passed to setLoopPoints().
Returns:
Loop Time position class.
See also:
void setLoopPoints(TimeSpan timePoints)
Sets the beginning and end of the sound’s looping sequence using Time.
Loop points allow one to specify a pair of positions such that, when the music is enabled for looping, it will seamlessly seek to the beginning whenever it encounters the end. Valid ranges for timePoints.offset and timePoints.length are [0, Dur) and (0, Dur-offset] respectively, where Dur is the value returned by getDuration(). Note that the EOF “loop point” from the end to the beginning of the stream is still honored, in case the caller seeks to a point after the end of the loop range. This function can be safely called at any point after a stream is opened, and will be applied to a playing sound without affecting the current playing offset.
Warning
Setting the loop points while the stream’s status is Paused will set its status to Stopped. The playing offset will be unaffected.
Parameters:
timePoints |
The definition of the loop. Can be any time points within the sound’s length |
See also: