BGE: add audio/video synchronization capability to VideoTexture

Add optional parameter to VideoTexture.Texture refresh() method
to specify timestamp (in seconds from start of movie) of the frame
to be loaded. This value is passed down to image source and for
VideoFFmpeg source, it is used instead of current time to load
the frame from the video file.

When combined with an audio actuator, it can be used to synchronize
the sound and the image: specify the same video file in the sound
actuator and use the KX_SoundActuator time attribute as timestamp
to refresh: the frame corresponding to the sound will be loaded:

GameLogic.video.refresh(True, soundAct.time)

1 files changed, 5 insertions, 2 deletions

diff --git a/source/gameengine/VideoTexture/VideoFFmpeg.h b/source/gameengine/VideoTexture/VideoFFmpeg.h
index b56984588c1..355c58c496b 100644
--- a/source/gameengine/VideoTexture/VideoFFmpeg.h
+++ b/source/gameengine/VideoTexture/VideoFFmpeg.h
@@ -129,6 +129,9 @@ protected:
 	/// end of file reached
 	bool m_eof;
 
+	/// flag to indicate that time is coming from application
+	bool m_externTime;
+
 	/// current file pointer position in file expressed in frame number
 	long m_curPosition;
 
@@ -154,10 +157,10 @@ protected:
 	STR_String m_imageName;
 
 	/// image calculation
-	virtual void calcImage (unsigned int texId);
+	virtual void calcImage (unsigned int texId, double ts);
 
 	/// load frame from video
-	void loadFrame (void);
+	void loadFrame (double ts);
 
 	/// set actual position
 	void setPositions (void);