OMK::Trajectory Class Reference
[Simulated ojects]

This Simulated object defines a position which moves in the space. More...

#include <OMKTrajectory.h>

Inheritance diagram for OMK::Trajectory:

[legend]Collaboration diagram for OMK::Trajectory:

[legend]List of all members.

Protected Member Functions
virtual void	computeParameters ()
	This part of the compute methods computes the associated data.
virtual bool	loadParameters (const ConfigurationParameterDescriptor *node)
	Configuration parameters loader of Trajectory.
Protected Attributes
std::vector< OMK::Type::Transform >	_targets
	The targets to follow.
Wm4::BSplineCurve3f *	_bSpline
	The B-spline.
float	_positionBetweenTargets
	Position between two points.
int	_currentTarget
	Current target.
Wm4::Vector3f	_refOrientation
	Reference orientation.
Type::Transform	_refPosition
	Reference position.
bool	_followOrientation
	Flag for orientation.
OMK::AttributeT< float >	_step
	The step to increase the position between two targets.
Private Member Functions
	DECLARE_OBJECT_FACTORY (Trajectory)

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Detailed Description

This Simulated object defines a position which moves in the space.

Configuration parameters are :

• Targets a set of transforms, only the translate will be used. The default is [ [[ 10 0 10]][[ 10 0 -10]][[-10 0 -10]][[-10 0 10]] ].
• Step a real value which defines the inscrement at each step, can be negative. A value of 0.001 means that it needs 1000 steps to go along the trajectory. Default is 0, this means no move.
• BSpline a boolean which indicates if the trajectory is a B-spline or a set of segments. Default is false.
• Degree a integer which is the degree of the B-spline, 1 is like no B-spline, the greatest it is the smoothest it is, BSpline must be activated. Default is 2.
• Position a transform, the initial position, only the rotate and the scale will be used, the translate is given by the first Targets.
• Orientation a boolean, if true the position follows the orientation of the trajectory, if false, it stays with the orientation given by Position. Default is false.

All the parameters have default values.

Example:

object1
{
  Class Trajectory
  Scheduling
  {
    ...
  }
  Extensions
  {
    ...
  }
  UserParams
  {
    Targets [ [[160 0 -400]] [[80 0 -540]] [[-80 0 -540]] [[-160 0 -400]] [[-80 0 -260]] [[80 0 -260]] ] // A hexagon
    Step 0.001
    BSpline on // At least 2 points to define a B-spline
    Degree 2 // Ignored if BSpline is disable, the greatest it is the smoothest it is
    Position [[0 0 0 ][1.57 1.57 0]]
  }
}

Somes extensions you can use with it

• Offset to change the reference point.

  Extensions
  { 
    offset
    {
      Class PostOffset
      Attribute Position
      Offset [[0 0 -100]]
    }
  }
  

• Plus/minus to change the speed by changing the step value.

  Extensions
  { 
    plus
    {
      Class PlusMinusFloatExtension
      Increment 0.001
      Key ADD
      Attribute Step
      VisuName visuOgre
    }
    minus
    {
      Class PlusMinusFloatExtension
      Increment -0.001
      Key SUBTRACT
      Attribute Step
      VisuName visuOgre
    }
  }
  

Definition at line 97 of file OMKTrajectory.h.

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Member Function Documentation

OMK::Trajectory::DECLARE_OBJECT_FACTORY

(

Trajectory

)

[private]

void Trajectory::computeParameters

(

)

[protected, virtual]

This part of the compute methods computes the associated data.

The inputs and outputs should work with associated data, you should use these associated data.

Reimplemented from OMK::ExtensibleSimulatedObject.

Definition at line 76 of file OMKTrajectory.cpp.

References _bSpline, _currentTarget, _followOrientation, OMK::SimplePoint::_position, _positionBetweenTargets, _refOrientation, _refPosition, _step, _targets, OMK::IAttributeT< PrmType, ModelType, AccessorType >::get(), OMK::Type::Transform::getRotate(), OMK::IAttributeT< PrmType, ModelType, AccessorType >::set(), OMK::Type::Transform::setRotate(), and OMK::Type::Transform::setTranslate().

{
  float step = _step.get() * ( _bSpline ? 1.0f : _targets.size() ) ;
  // Get the increment
  if ( 1.0f <= _positionBetweenTargets ) 
  { // step > 0
    _currentTarget = ( _currentTarget + 1 ) % _targets.size() ;
    _positionBetweenTargets = step ;
  }
  else if ( _positionBetweenTargets <= 0.0f ) 
  { // step < 0
    _currentTarget = ( _currentTarget + _targets.size() - 1 ) % _targets.size() ;
    _positionBetweenTargets = 1.0f + step ;
  }
  else
  {
    _positionBetweenTargets += step ;
  }
  
  // Get the translate and the rotate
  OMK::Type::Transform position( _refPosition ) ;
  Wm4::Vector3f orientation ;
  if( _bSpline )
  { // For B-spline
    if( _followOrientation ) 
    {
      Wm4::Vector3f translate ;
      _bSpline->Get( _positionBetweenTargets, &translate, &orientation, 0, 0 ) ;
      position.setTranslate( translate ) ;
    }
    else
    {
      position.setTranslate( _bSpline->GetPosition( _positionBetweenTargets ) ) ;
    }
  }
  else
  { // For segments
    int previousTarget( ( _currentTarget + _targets.size() - 1 ) % _targets.size() ) ;
    orientation = _targets[ _currentTarget ].getTranslate() - _targets[ previousTarget ].getTranslate() ;
    position.setTranslate( _targets[previousTarget].getTranslate() + orientation * _positionBetweenTargets ) ;
  }
  
  if( _followOrientation ) 
  { // Calculate the orientation
    orientation.Normalize() ;
    Wm4::Vector3f axis( orientation.Cross( _refOrientation ) ) ;
    axis.Normalize() ;
    float angle = -Wm4::Math<float>::ACos( orientation.Dot( _refOrientation ) ) ;
    Wm4::Matrix3f rotationMatrix( axis, angle ) ;
    position.setRotate( position.getRotate() * rotationMatrix ) ;
  }
  // Set the new position
  _position.set( position ) ;
}

bool Trajectory::loadParameters

(

const ConfigurationParameterDescriptor *

node

)

[protected, virtual]

Configuration parameters loader of Trajectory.

Parameters:

[in]

node

the root node of the configuration parameter.

Returns:

true if all needed parameters can be read.

Reads in the configuration node the values to set the attributs.

Reimplemented from OMK::ExtensibleSimulatedObject.

Definition at line 33 of file OMKTrajectory.cpp.

References _bSpline, _followOrientation, OMK::SimplePoint::_position, _refOrientation, _refPosition, _targets, OMK::IAttributeT< PrmType, ModelType, AccessorType >::get(), OMK::ParametersAccessor::get(), OMK::ExtensibleSimulatedObject::loadParameters(), OMK::IAttributeT< PrmType, ModelType, AccessorType >::set(), OMK::Type::Transform::setTranslate(), and OMK::IAttributeT< PrmType, ModelType, AccessorType >::setValueToOutput().

{
  SimplePoint::loadParameters( node ) ;
  if( !ParametersAccessor::get( node, "Targets", _targets ) )
  {
    _targets.push_back( Transform( Wm4::Vector3f(  10, 0,  10 ) ) ) ;
    _targets.push_back( Transform( Wm4::Vector3f(  10, 0, -10 ) ) ) ;
    _targets.push_back( Transform( Wm4::Vector3f( -10, 0, -10 ) ) ) ;
    _targets.push_back( Transform( Wm4::Vector3f( -10, 0,  10 ) ) ) ;
  }
  ParametersAccessor::get( node, "Orientation", _followOrientation ) ;
  bool bspline = false ;
  ParametersAccessor::get( node, "BSpline", bspline ) ;
  if( bspline && 2 <= _targets.size() )
  { // At least 2 points to define a B-spline
    int degree = 2 ; // Default value
    ParametersAccessor::get( node, "Degree", degree ) ;
    degree = degree < (int)_targets.size() ? degree : _targets.size() - 1 ;
    Wm4::Vector3f* targets = new Wm4::Vector3f[ _targets.size() ] ;
    for( unsigned int i = 0 ; i < _targets.size() ; i++ )
    {
      targets[ i ] = _targets[ i ].getTranslate() ;
    }
    _bSpline = new Wm4::BSplineCurve3f( _targets.size(), targets, degree, true, false ) ;
    delete[] targets ;
    _refOrientation = _bSpline->GetFirstDerivative( 0.0f ) ;
    _refOrientation.Normalize() ;
  }
  else
  {
    _refOrientation = _targets[ 1 ].getTranslate() - _targets[ 0 ].getTranslate() ;
    _refOrientation.Normalize() ;
  }
  
  _refPosition = _position.get() ;
  OMK::Type::Transform position( _refPosition ) ;
  position.setTranslate( _targets[ 0 ].getTranslate() ) ;
  _position.set( position ) ;
  _position.setValueToOutput() ;
  return true ; 
}

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Member Data Documentation

std::vector< OMK::Type::Transform > OMK::Trajectory::_targets [protected]

The targets to follow.

Definition at line 111 of file OMKTrajectory.h.

Referenced by computeParameters(), and loadParameters().

Wm4::BSplineCurve3f* OMK::Trajectory::_bSpline [protected]

The B-spline.

This one is defined only if there is a B-spline.

Definition at line 114 of file OMKTrajectory.h.

Referenced by computeParameters(), and loadParameters().

float OMK::Trajectory::_positionBetweenTargets [protected]

Position between two points.

Its value is in the set [0, 1[

Definition at line 117 of file OMKTrajectory.h.

Referenced by computeParameters().

int OMK::Trajectory::_currentTarget [protected]

Current target.

Definition at line 119 of file OMKTrajectory.h.

Referenced by computeParameters().

Wm4::Vector3f OMK::Trajectory::_refOrientation [protected]

Reference orientation.

Definition at line 121 of file OMKTrajectory.h.

Referenced by computeParameters(), and loadParameters().

Type::Transform OMK::Trajectory::_refPosition [protected]

Reference position.

Definition at line 123 of file OMKTrajectory.h.

Referenced by computeParameters(), and loadParameters().

bool OMK::Trajectory::_followOrientation [protected]

Flag for orientation.

Definition at line 125 of file OMKTrajectory.h.

Referenced by computeParameters(), and loadParameters().

OMK::AttributeT< float > OMK::Trajectory::_step [protected]

The step to increase the position between two targets.

Definition at line 128 of file OMKTrajectory.h.

Referenced by computeParameters().

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