transport reference

ReferenceCopy Anchor Link

Every function of the transport flow: what it takes, what it returns, what it refuses, and how it undoes. A Result<T> is Ok(T) or a SuperbError; the errors listed are the ones you can cause.

startCopy Anchor Link

pub fn start(session: &mut Session) -> Result<()>

Starts playing from where the playhead is. Rebuilds the mixer first if the memory changed since it was built.

Takes

• session: &mut Session — the open session, borrowed mutably

Returns Result<()> — nothing

Errors the mixer cannot be built (the memory names audio that is not in memory, say); the command queue is full.

Undo none: not an edit.

Made of session::steps::rebuild when needed → EngineHandle::send(Play).

Example

transport::start(&mut session)?;

stopCopy Anchor Link

pub fn stop(session: &mut Session) -> Result<()>

Stops the transport where it is.

Takes

• session: &mut Session — the open session, borrowed mutably

Returns Result<()> — nothing

Errors the command queue is full.

Undo none: not an edit.

Made of EngineHandle::send(Stop).

Example

transport::stop(&mut session)?;

seekCopy Anchor Link

pub fn seek(session: &mut Session, to: TimePosition) -> Result<()>

Moves the playhead. Works while stopped or rolling.

Takes

• session: &mut Session — the open session, borrowed mutably
• to: TimePosition — where to put the playhead

Returns Result<()> — nothing

Errors the command queue is full.

Undo none: not an edit.

Made of EngineHandle::send(Seek).

Example

transport::seek(&mut session, TimePosition::from_seconds(30.0, rate))?;

rewindCopy Anchor Link

pub fn rewind(session: &mut Session) -> Result<()>

Moves the playhead to the start of the session.

Takes

• session: &mut Session — the open session, borrowed mutably

Returns Result<()> — nothing

Errors the command queue is full.

Undo none: not an edit.

Made of seek to zero.

Example

transport::rewind(&mut session)?;

loopingCopy Anchor Link

pub fn looping(session: &mut Session, on: bool) -> Result<()>

Turns looping over the session's loop range on or off (set the range with session::set_loop). State, like mute: saved with the session, applied at the engine's next block, not an undo step.

Takes

• session: &mut Session — the open session, borrowed mutably
• on: bool — true to switch on, false to switch off

Returns Result<()> — nothing

Errors the command queue is full.

Undo none: state, not an edit (saved through the state file, see session::state_file).

Made of Memory::set_looping through session::set_state → EngineHandle::send(SetLoopEnabled).

Example

transport::looping(&mut session, true)?;

playheadCopy Anchor Link

pub fn playhead(session: &Session) -> TimePosition

Where the playhead is: the position after the last block the engine rendered, or where the last seek sent it if no block has run since.

Takes

• session: &Session — the open session, borrowed

Returns TimePosition — where the playhead is after the last block the engine rendered, in samples

Errors never; a query.

Undo none.

Example

let seconds = transport::playhead(&session).to_seconds(rate);

stateCopy Anchor Link

pub fn state(session: &Session) -> TransportState

The transport state after the last block the engine rendered.

Takes

• session: &Session — the open session, borrowed

Returns TransportState — TransportState::Stopped, Playing or Recording, as of the last rendered block

Errors never; a query.

Undo none.

Example

if transport::state(&session).is_rolling() { /* draw a moving playhead */ }