promeki::SDLPlayerWidget Class Reference

Widget that plays frames through an SDLPlayerMediaIO. More...

#include <sdlplayerwidget.h>

Inheritance diagram for promeki::SDLPlayerWidget:

Collaboration diagram for promeki::SDLPlayerWidget:

Public Member Functions
	SDLPlayerWidget (SDLAudioOutput *audio=nullptr, bool useAudioClock=true, ObjectBase *parent=nullptr)
	Constructs an SDLPlayerWidget.
MediaIO *	mediaIO () const
	Returns the MediaIO the widget consumes frames through.
SDLPlayerMediaIO *	task () const
	Returns the underlying task (may be useful for tests).
FrameCount	framesPresented () const
	Total frames the widget has presented since construction.
void	togglePause ()
	Toggles the playback clock's pause state.
bool	isPaused () const
	Returns true when the playback clock is paused.
Public Member Functions inherited from promeki::SDLVideoWidget
	SDLVideoWidget (ObjectBase *parent=nullptr)
	Constructs an SDLVideoWidget.
	~SDLVideoWidget ()
	Destructor. Frees the SDL texture.
void	setPayload (const UncompressedVideoPayload::Ptr &payload)
	Sets the payload to display.
void	setScaleMode (ScaleMode mode)
	Sets the scaling mode.
ScaleMode	scaleMode () const
	Returns the current scaling mode.

Protected Member Functions
void	keyPressEvent (KeyEvent *e) override
	Handles Key_Space by toggling pause.
Protected Member Functions inherited from promeki::SDLVideoWidget
void	paintEvent (PaintEvent *e) override

Friends
class	SDLPlayerMediaIO

Additional Inherited Members
Public Types inherited from promeki::SDLVideoWidget
enum	ScaleMode { ScaleNone , ScaleFit , ScaleStretch }
	Scaling mode for displayed images. More...
Static Public Member Functions inherited from promeki::SDLVideoWidget
static uint32_t	mapPixelFormat (const PixelFormat &pd)
	Maps a promeki PixelFormat to an SDL pixel format.
static uint32_t	mapColorspace (const PixelFormat &pd)
	Maps a promeki PixelFormat to an SDL_Colorspace.
static bool	isDirectlyMappable (const PixelFormat &pd)
	Returns whether a format can skip CSC conversion on upload.

Detailed Description

Widget that plays frames through an SDLPlayerMediaIO.

SDLPlayerWidget subclasses SDLVideoWidget so it paints frames directly, and owns the MediaIO / SDLPlayerMediaIO pair that consumes frames. Clients retrieve the sink via mediaIO and write frames as they would with any MediaIO backend.

Pause control

The widget is the player's keyboard surface. With FocusPolicy::StrongFocus set at construction, the SDL subsystem routes key events here when the app gives it focus (setFocus or explicit SdlSubsystem::setFocusedWidget). The space key toggles the playback clock's pause state; other keys are left unaccepted so the SdlSubsystem walk propagates them up the parent chain.

Ownership

The widget owns the MediaIO, which owns the task. The task holds a back-pointer to this widget so its pull thread can call back into presentImage — safe because the destruction order guarantees the MediaIO (and therefore the task + its threads) is torn down before the widget's bases.

Example

SDLWindow        window("player", 1280, 720);
SDLAudioOutput   audio(&window);
SDLPlayerWidget  player(&audio, true, &window);
player.setFocus();
window.show();
 
MediaIO *mio = player.mediaIO();
mio->open();
// ... write frames via mio->sink(0)->writeFrame(...) ...

Thread Safety

Thread-affine — see SDLVideoWidget. Frames may be delivered from any thread via the owned MediaIO sink (which marshals onto its own task threads); only the widget API itself (focus, geometry, lifecycle) is restricted to the SDL event thread.

Constructor & Destructor Documentation

SDLPlayerWidget()

promeki::SDLPlayerWidget::SDLPlayerWidget ( SDLAudioOutput *  audio = nullptr, bool  useAudioClock = true, ObjectBase *  parent = nullptr  )

explicit

Constructs an SDLPlayerWidget.

Creates the owned SDLPlayerMediaIO / MediaIO pair and sets FocusPolicy::StrongFocus on the widget so the app can setFocus on it to receive key events.

Parameters

audio	Audio output (may be nullptr).
useAudioClock	Prefer the audio device as the timing source (default true).
parent	Optional parent widget / window.

Member Function Documentation

keyPressEvent()

void promeki::SDLPlayerWidget::keyPressEvent ( KeyEvent *  e )

overrideprotected

Handles Key_Space by toggling pause.

All other key codes are left unaccepted so the SDL subsystem's parent-chain walk propagates them upward.

togglePause()

void promeki::SDLPlayerWidget::togglePause

(

)

Toggles the playback clock's pause state.

No-op when no MediaIO is currently open (i.e. no pause-capable clock exists yet).

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The documentation for this class was generated from the following file:

• include/promeki/sdl/sdlplayerwidget.h