Tekkotsu: MotionSequenceEngine Class Reference

Each outputs is handled independently. It's easy to add keyframes which modify all of the outputs, but since each output is tracked individually, OutputCmd's with 0 weight can be used to not affect other motions. For instance, if you want to pan the head left to right while moving the right leg up and down several times, you won't have to specify the intermediary position of the head in its motion at each of the leg motion keyframes.

Be aware that the 0 time frame will be replaced on a call to play() with the current body posture from state. However, this only applies to outputs which have a non-zero weighted frame defined at some point. The weights, of the 0 time frame will remain unchanged. These weights are initially set to 0, so that it's possible to 'fade in' the first frame of the motion sequence from whereever the body happens to be (or already doing)

To fade out at the end, set a frame with 0 weight for everything. Otherwise it will simply die suddenly. When a joint reaches its last keyframe, if hold is set (the default) it will hold its last value until the MotionSequence is reset or stopped. If hold is false, then the joint is treated as 0 weight once it reaches its last frame.

Currently, MotionSequenceEngine is intended mainly for building, not editing. It's easy to add keyframes, but hard/impossible to delete them.

The MotionSequenceEngine base class is an abstract class so that you can create memory efficient motion sequences and simply refer to them by the common base class instead of having to worry about the actual size allocated in the template, MotionSequenceMC.

Lines beginning with '#' are ignored as comments. Be aware if you load the file and then save it again, these comments will be lost.

Example 1: This motion sequence will straighten out the head, panning from right to left.

#MSq 
degrees

# Straighten head
advanceTime  50 
NECK:tilt       15 
NECK:nod       0

# Pan right
advanceTime  850 
NECK:pan~       -45

# Pan left
advanceTime  900 
NECK:pan~       45 
NECK:tilt       15 
NECK:nod       0

#END

Example 2: This example will straighten the head and the tail, pan the head left to right, and then pan the tail left to right.

#MSq
degrees

# Bring head and tail to neural positions
advanceTime 50
NECK:pan~ 0
NECK:tilt 0
TAIL:pan~ 0
TAIL:tilt 0

# Pan left
advanceTime 1000
NECK:pan~ 90
# Pan right
advanceTime 1000
NECK:pan~ -90

# Center head
# Update tail time index
advanceTime 500
NECK:pan~ 0
# Note this respecification of TAIL:pan~ at 0 -- see graph below
TAIL:pan~ 0

# Wag left
advanceTime 500
TAIL:pan~ 90
# Wag right
advanceTime 500
TAIL:pan~ -90

#END

After loading a motion sequence, the playtime is left at the end. This is to make it easy to append/overlay motion sequences. However, the playhead will be reset to the beginning on the first call to updateOutputs() if isPlaying() returns true.

  //This code sample will stand up, point the head forward and up 0.1 radians,
  //and then autoprune

  //First declare the MotionSequence itself:
  SharedObject< MotionSequenceMC<MotionSequenceEngine::SizeSmall> > stand;

  //Over the course of the first 700 milliseconds, go to standing posture:
  standSit->setTime(700);
  standSit->setPose(PostureEngine("stand.pos"));
  // could also use standSit->loadFile("stand.pos")

  //Then take another 700 milliseconds to straighten out the head:
  standSit->advanceTime(700);
  //We'll set joints individually this time, instead of loading a posture file:
  standSit->setOutputCmd(HeadOffset+PanOffset,0);
  standSit->setOutputCmd(HeadOffset+RollOffset,0);
  standSit->setOutputCmd(HeadOffset+TiltOffset,0.1); //look up .1 radians

  //Add to MotionManager:
  motman->addPrunableMotion(standSit);
  //Playback will now begin automatically, and region deallocated when done

By default, playing is true. Thus, when you add a MotionSequenceMC to the MotionManager, it will begin executing automatically. If you do not want this behavior, simply call pause() before adding the sequence.

When the sequence reaches the end, isAlive() will return false. If the motion was added with MotionManager::addPrunableMotion, the motion sequence will then autoprune itself from the MotionManager. However, you can either call MotionManager::addPersistentMotion() to add it, or call setAutoPrune(false), if you want to retain the same instantiation between executions.

Definition at line 185 of file MotionSequenceEngine.h.


Public Member Functions
	MotionSequenceEngine ()
	constructor, will start playing immediately
virtual	~MotionSequenceEngine ()
	destructor
virtual int	updateOutputs ()
	similar to the MotionCommand::updateOutputs, although this isn't a motion command, and doesn't make any calls on MotionManager - merely updates lasttime, expects subclasses to do the work of sending new commands to the system
LoadSave related
virtual unsigned int	getBinSize () const
	inherited, returns the size used to save the sequence
virtual unsigned int	loadBuffer (const char buf[], unsigned int len)
	inherited, doesn't clear before loading - call clear yourself if you want to reset, otherwise it will overlay. Leaves playtime at end of load.
virtual unsigned int	saveBuffer (char buf[], unsigned int len) const
	inherited, saves the motion sequence - will save a flat file - doesn't remember references to other files which were loaded
virtual unsigned int	loadFile (const char filename[])
	inherited, doesn't clear before loading - call clear yourself if you want to reset, otherwise it will overlay. Leaves playtime at end of load.
virtual unsigned int	saveFile (const char filename[]) const
	inherited, saves the motion sequence - will save a flat file - doesn't remember references to other files which were loaded
void	setSaveDegrees ()
	will store angles as degrees on future saves
bool	isSaveDegrees () const
	returns true if will store angles as degrees on future saves
void	setSaveRadians ()
	will store angles as radians on future saves
bool	isSaveRadians () const
	returns true if will store angles as degrees on future saves
Sequence Construction
virtual void	clear ()=0
	empties out the sequence (constant time operation - faster than a series of pops)
void	setTime (unsigned int x)
	set the time for both playback and editing (in milliseconds)
unsigned int	advanceTime (unsigned int x)
	advance the play/edit index by x milliseconds, and then returns the new getTime()
void	setOutputCmd (unsigned int i, const OutputCmd &cmd)
	will insert a keyframe for the given output, or change an existing one
const OutputCmd &	getOutputCmd (unsigned int i)
	gets the value of output i at the playhead
void	setPose (const PostureEngine &pose)
	calls setOutputCmd for all non-zero weighted OutputCmds in pose (if you wish to set from a file, use loadFile)
void	setExplicitPose (const PostureEngine &pose)
	calls setOutputCmd on each of the OutputCmds in pose, even if they are zero-weight (can be used to fade joints in/out with other conflicting motions)
PostureEngine	getPose ()
	returns the set of OutputCmd's at the current playhead as a PostureEngine
void	getPose (PostureEngine &pose)
	stores the set of OutputCmd's at the current playhead into the specified PostureEngine
void	overlayPose (const PostureEngine &pose) __attribute__((__deprecated__))
	deprecated, use setPose instead (what setPose used to do is now setExplicitPose)
unsigned int	overlayMotion (const std::string &msFile)
	loads msFile from disk and calls overlayMotion(const MotionSequenceEngine&) with it, returns the duration of msFile (0 if there was an error)
void	overlayMotion (const MotionSequenceEngine &ms)
	applies each keyframe of ms to this, leaves playhead at the end (in other words, advances playhead to end of ms)
void	compress ()
	compresses the sequence by eliminating sequences of moves which are identical
virtual unsigned int	getMaxFrames () const =0
	returns the maximum number of key frames (Move's) which can be stored, determined by the instantiating MotionSequenceMC's template parameter
virtual unsigned int	getUsedFrames () const =0
	returns the number of used key frames (Move's) which have been stored by the instantiation MotionSequenceEngine subclass
void	makeSafe (const float vels[NumOutputs], float margin)
	will insert time into the motion where needed to keep the joint velocities at or below the speeds given in vels * margin
Playback Control
bool	isPlaying ()
void	play ()
	returns true if currently playing restarts playback from beginning
void	pause ()
	pauses playback until another call to play() or resume()
void	resume ()
	begins playback from the current playtime
unsigned int	getTime () const
	returns the current position of the playback (in milliseconds), see setTime()
unsigned int	getEndTime () const
	returns the length of the motion sequence (in milliseconds)
void	setSpeed (float x)
	sets the playback speed (e.g. 1=regular, 0.5=half speed, -1=backwards)
float	getSpeed () const
	returns the playback speed
virtual void	setHold (bool h=true)
	Sets hold - if this is set to false, it will allow a persistent motion to behave the same as a pruned motion, without being pruned.
virtual bool	getHold ()
	return hold
Protected Types
typedef unsigned short	Move_idx_t
	type for indexes to move structures in subclass's storage
Protected Member Functions
virtual Move &	getKeyFrame (Move_idx_t x)=0
	returns the Move struct corresponding to x in the subclass's actual data structure
virtual const Move &	getKeyFrame (Move_idx_t x) const =0
	returns the Move struct corresponding to x in the subclass's actual data structure
virtual Move_idx_t	newKeyFrame ()=0
	causes subclass to create a new Move structure, returns its index
virtual void	eraseKeyFrame (Move_idx_t x)=0
	causes subclass to mark the corresponding Move structure as free
void	calcOutput (OutputCmd &ans, unsigned int t, const Move &prev, const Move &next) const
	Does the actual calculation of position information. Perhaps replace with a Bezier or spline or something?
virtual bool	setRange (unsigned int t, Move_idx_t &prev, Move_idx_t &next) const =0
	Sets prev and next to the appropriate values for the given time and output index, return true if there was a change.
unsigned int	setNextFrameTime (Move_idx_t p[NumOutputs], Move_idx_t n[NumOutputs]) const
	sets playtime to next time for which any output has a keyframe, -1 if none exists
Static Protected Member Functions
static unsigned int	readWord (const char buf[], const char *const buflen, char word[], const unsigned int wordlen)
	reads a line from a file, parsing it into variables, returns ending position
static unsigned int	getOutputIndex (const char name[], unsigned int i)
	returns the index for the output named in the string or NumOutputs if not found, begins search through RobotInfo::outputName's at index i
Protected Attributes
Move_idx_t	starts [NumOutputs]
	the beginning frame for each output animation
Move_idx_t	prevs [NumOutputs]
	the previous frame (the starttime for this frame will always be less than or equal to playtime)
Move_idx_t	nexts [NumOutputs]
	the upcoming frame (the starttime for this frame will always be greater than playtime)
OutputCmd	curs [NumOutputs]
	merely a cache of current values (if computed, see curstamps)
unsigned int	curstamps [NumOutputs]
	timestamp of corresponding value in curs
unsigned int	playtime
	the current time of playback, 0 is start of sequence
unsigned int	lasttime
	the time of the last update
unsigned int	endtime
	max of moves's Move::starttime's
float	playspeed
	multiplies the difference between current time and starttime, negative will cause play backwards
bool	playing
	true if playing, false if paused
bool	hold
	if set to true, the posture will be kept active; otherwise joints will be marked unused after each posture is achieved (as if the posture was pruned); set through setHold()
float	loadSaveMode
	1 to use radians, M_PI/180 for degrees during a save
Static Protected Attributes
static Move_idx_t	invalid_move = (MotionSequenceEngine::Move_idx_t)-1
	used to mark the ends of the Move linked lists
Classes
struct	Move
	This struct holds all the information needed about a frame for a particular output. More...

Member Function Documentation

void MotionSequenceEngine::overlayMotion ( const MotionSequenceEngine & ms )

applies each keyframe of ms to this, leaves playhead at the end (in other words, advances playhead to end of ms)

Todo:: should better handle conflicts with keyframes in original motion

This is not a particularly well implemented function -- it will interleave ms's keyframes with any pre-existing ones, but will clobber frames which coincide with ms's own. Probably will not give the desired effect when the motion is actually overlaying something, but it will work for basic usage cases.

Definition at line 398 of file MotionSequenceEngine.cc.

MotionSequenceEngine Class Reference

Detailed Description

Public Member Functions

Protected Types

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Static Protected Attributes

Classes

Member Function Documentation