#include <QGLViewer/frame.h>

The Frame class represents a coordinate system, defined by a position and an orientation. More...

Inheritance diagram for qglviewer::Frame:

Detailed Description

The Frame class represents a coordinate system, defined by a position and an orientation.

A Frame is a 3D coordinate system, represented by a position() and an orientation(). The order of these transformations is important: the Frame is first translated and then rotated around the new translated origin.

A Frame is useful to define the position and orientation of a 3D rigid object, using its matrix() method, as shown below:

// Builds a Frame at position (0.5,0,0) and oriented such that its Y axis is
along the (1,1,1)
// direction. One could also have used setPosition() and setOrientation().
Frame fr(Vec(0.5,0,0), Quaternion(Vec(0,1,0), Vec(1,1,1)));
glPushMatrix();
glMultMatrixd(fr.matrix());
// Draw your object here, in the local fr coordinate system.
glPopMatrix();

Many functions are provided to transform a 3D point from one coordinate system (Frame) to an other: see coordinatesOf(), inverseCoordinatesOf(), coordinatesOfIn(), coordinatesOfFrom()...

You may also want to transform a 3D vector (such as a normal), which corresponds to applying only the rotational part of the frame transformation: see transformOf() and inverseTransformOf(). See the frameTransform example for an illustration.

The translation() and the rotation() that are encapsulated in a Frame can also be used to represent a rigid transformation of space. Such a transformation can also be interpreted as a change of coordinate system, and the coordinate system conversion functions actually allow you to use a Frame as a rigid transformation. Use inverseCoordinatesOf() (resp. coordinatesOf()) to apply the transformation (resp. its inverse). Note the inversion.

Hierarchy of Frames

The position and the orientation of a Frame are actually defined with respect to a referenceFrame(). The default referenceFrame() is the world coordinate system (represented by a nullptr referenceFrame()). If you setReferenceFrame() to a different Frame, you must then differentiate:

the local translation() and rotation(), defined with respect to the referenceFrame(),

the global position() and orientation(), always defined with respect to the world coordinate system.

A Frame is actually defined by its translation() with respect to its referenceFrame(), and then by a rotation() of the coordinate system around the new translated origin.

This terminology for local (translation() and rotation()) and global (position() and orientation()) definitions is used in all the methods' names and should be sufficient to prevent ambiguities. These notions are obviously identical when the referenceFrame() is nullptr, i.e. when the Frame is defined in the world coordinate system (the one you are in at the beginning of the QGLViewer::draw() method, see the introduction page).

Frames can hence easily be organized in a tree hierarchy, which root is the world coordinate system. A loop in the hierarchy would result in an inconsistent (multiple) Frame definition. settingAsReferenceFrameWillCreateALoop() checks this and prevents setReferenceFrame() from creating such a loop.

This frame hierarchy is used in methods like coordinatesOfIn(), coordinatesOfFrom()... which allow coordinates (or vector) conversions from a Frame to any other one (including the world coordinate system).

However, one must note that this hierarchical representation is internal to the Frame classes. When the Frames represent OpenGL coordinates system, one should map this hierarchical representation to the OpenGL GL_MODELVIEW matrix stack. See the matrix() documentation for details.

Constraints

An interesting feature of Frames is that their displacements can be constrained. When a Constraint is attached to a Frame, it filters the input of translate() and rotate(), and only the resulting filtered motion is applied to the Frame. The default constraint() is nullptr resulting in no filtering. Use setConstraint() to attach a Constraint to a frame.

Constraints are especially usefull for the ManipulatedFrame instances, in order to forbid some mouse motions. See the constrainedFrame, constrainedCamera and luxo examples for an illustration.

Classical constraints are provided for convenience (see LocalConstraint, WorldConstraint and CameraConstraint) and new constraints can very easily be implemented.

Derived classes

The ManipulatedFrame class inherits Frame and implements a mouse motion convertion, so that a Frame (and hence an object) can be manipulated in the scene with the mouse.

Public Member Functions
	Frame ()
	Creates a default Frame. More...

virtual	~Frame ()
	Virtual destructor. More...

	Frame (const Frame &frame)
	Copy constructor. More...

Frame &	operator= (const Frame &frame)
	Equal operator. More...

Signals
void	modified ()
	This signal is emitted whenever the position() or the orientation() of the Frame is modified. More...

void	interpolated ()
	This signal is emitted when the Frame is interpolated by a KeyFrameInterpolator. More...

XML representation
virtual QDomElement	domElement (const QString &name, QDomDocument &document) const
	Returns an XML `QDomElement` that represents the Frame. More...

virtual void	initFromDOMElement (const QDomElement &element)
	Restores the Frame state from a `QDomElement` created by domElement(). More...

World coordinates position and orientation
	Frame (const Vec &position, const Quaternion &orientation)
	Creates a Frame with a position() and an orientation(). More...

void	setPosition (const Vec &position)
	Sets the position() of the Frame, defined in the world coordinate system. More...

void	setPosition (qreal x, qreal y, qreal z)
	Same as setPosition(), but with `qreal` parameters. More...

void	setPositionWithConstraint (Vec &position)
	Same as setPosition(), but `position` is modified so that the potential constraint() of the Frame is satisfied. More...

void	setOrientation (const Quaternion &orientation)
	Sets the orientation() of the Frame, defined in the world coordinate system. More...

void	setOrientation (qreal q0, qreal q1, qreal q2, qreal q3)
	Same as setOrientation(), but with `qreal` parameters. More...

void	setOrientationWithConstraint (Quaternion &orientation)
	Same as setOrientation(), but `orientation` is modified so that the potential constraint() of the Frame is satisfied. More...

void	setPositionAndOrientation (const Vec &position, const Quaternion &orientation)
	Same as successive calls to setPosition() and then setOrientation(). More...

void	setPositionAndOrientationWithConstraint (Vec &position, Quaternion &orientation)
	Same as setPositionAndOrientation() but `position` and `orientation` are modified to satisfy the constraint. More...

Vec	position () const
	Returns the position of the Frame, defined in the world coordinate system. More...

Quaternion	orientation () const
	Returns the orientation of the Frame, defined in the world coordinate system. More...

void	getPosition (qreal &x, qreal &y, qreal &z) const
	`x`, `y` and `z` are set to the position() of the Frame. More...

void	getOrientation (qreal &q0, qreal &q1, qreal &q2, qreal &q3) const
	Get the current orientation of the frame (same as orientation()). More...

Local translation and rotation w/r reference Frame
void	setTranslation (const Vec &translation)
	Sets the translation() of the frame, locally defined with respect to the referenceFrame(). More...

void	setTranslation (qreal x, qreal y, qreal z)
	Same as setTranslation(), but with `qreal` parameters. More...

void	setTranslationWithConstraint (Vec &translation)
	Same as setTranslation(), but `translation` is modified so that the potential constraint() of the Frame is satisfied. More...

void	setRotation (const Quaternion &rotation)
	Set the current rotation Quaternion. More...

void	setRotation (qreal q0, qreal q1, qreal q2, qreal q3)
	Same as setRotation() but with `qreal` Quaternion parameters. More...

void	setRotationWithConstraint (Quaternion &rotation)
	Same as setRotation(), but `rotation` is modified so that the potential constraint() of the Frame is satisfied. More...

void	setTranslationAndRotation (const Vec &translation, const Quaternion &rotation)
	Same as successive calls to setTranslation() and then setRotation(). More...

void	setTranslationAndRotationWithConstraint (Vec &translation, Quaternion &rotation)
	Same as setTranslationAndRotation(), but `translation` and `orientation` are modified to satisfy the constraint(). More...

Vec	translation () const
	Returns the Frame translation, defined with respect to the referenceFrame(). More...

Quaternion	rotation () const
	Returns the Frame rotation, defined with respect to the referenceFrame(). More...

void	getTranslation (qreal &x, qreal &y, qreal &z) const
	Fill `x`, `y` and `z` with the translation() of the Frame. More...

void	getRotation (qreal &q0, qreal &q1, qreal &q2, qreal &q3) const
	The `q` are set to the rotation() of the Frame. More...

Frame hierarchy
const Frame *	referenceFrame () const
	Returns the reference Frame, in which coordinates system the Frame is defined. More...

void	setReferenceFrame (const Frame *const refFrame)
	Sets the referenceFrame() of the Frame. More...

bool	settingAsReferenceFrameWillCreateALoop (const Frame *const frame)
	Returns `true` if setting `frame` as the Frame's referenceFrame() would create a loop in the Frame hierarchy. More...

Frame modification
void	translate (Vec &t)
	Same as translate(const Vec&) but `t` may be modified to satisfy the translation constraint(). More...

void	translate (const Vec &t)
	Translates the Frame of `t` (defined in the Frame coordinate system). More...

void	translate (qreal x, qreal y, qreal z)
	Same as translate(const Vec&) but with `qreal` parameters. More...

void	translate (qreal &x, qreal &y, qreal &z)
	Same as translate(Vec&) but with `qreal` parameters. More...

void	rotate (Quaternion &q)
	Same as rotate(const Quaternion&) but `q` may be modified to satisfy the rotation constraint(). More...

void	rotate (const Quaternion &q)
	Rotates the Frame by `q` (defined in the Frame coordinate system): R = R*q. More...

void	rotate (qreal q0, qreal q1, qreal q2, qreal q3)
	Same as rotate(const Quaternion&) but with `qreal` Quaternion parameters. More...

void	rotate (qreal &q0, qreal &q1, qreal &q2, qreal &q3)
	Same as rotate(Quaternion&) but with `qreal` Quaternion parameters. More...

void	rotateAroundPoint (Quaternion &rotation, const Vec &point)
	Makes the Frame rotate() by `rotation` around `point`. More...

void	rotateAroundPoint (const Quaternion &rotation, const Vec &point)
	Same as rotateAroundPoint(), but with a `const` `rotation` Quaternion. More...

void	alignWithFrame (const Frame *const frame, bool move=false, qreal threshold=0.0)
	Aligns the Frame with `frame`, so that two of their axis are parallel. More...

void	projectOnLine (const Vec &origin, const Vec &direction)
	Translates the Frame so that its position() lies on the line defined by `origin` and `direction` (defined in the world coordinate system). More...

Coordinate system transformation of 3D coordinates
Vec	coordinatesOf (const Vec &src) const
	Returns the Frame coordinates of a point `src` defined in the world coordinate system (converts from world to Frame). More...

Vec	inverseCoordinatesOf (const Vec &src) const
	Returns the world coordinates of the point whose position in the Frame coordinate system is `src` (converts from Frame to world). More...

Vec	localCoordinatesOf (const Vec &src) const
	Returns the Frame coordinates of a point `src` defined in the referenceFrame() coordinate system (converts from referenceFrame() to Frame). More...

Vec	localInverseCoordinatesOf (const Vec &src) const
	Returns the referenceFrame() coordinates of a point `src` defined in the Frame coordinate system (converts from Frame to referenceFrame()). More...

Vec	coordinatesOfIn (const Vec &src, const Frame *const in) const
	Returns the `in` coordinates of the point whose position in the Frame coordinate system is `src` (converts from Frame to `in`). More...

Vec	coordinatesOfFrom (const Vec &src, const Frame *const from) const
	Returns the Frame coordinates of the point whose position in the `from` coordinate system is `src` (converts from `from` to Frame). More...

void	getCoordinatesOf (const qreal src[3], qreal res[3]) const
	Same as coordinatesOf(), but with `qreal` parameters. More...

void	getInverseCoordinatesOf (const qreal src[3], qreal res[3]) const
	Same as inverseCoordinatesOf(), but with `qreal` parameters. More...

void	getLocalCoordinatesOf (const qreal src[3], qreal res[3]) const
	Same as localCoordinatesOf(), but with `qreal` parameters. More...

void	getLocalInverseCoordinatesOf (const qreal src[3], qreal res[3]) const
	Same as localInverseCoordinatesOf(), but with `qreal` parameters. More...

void	getCoordinatesOfIn (const qreal src[3], qreal res[3], const Frame *const in) const
	Same as coordinatesOfIn(), but with `qreal` parameters. More...

void	getCoordinatesOfFrom (const qreal src[3], qreal res[3], const Frame *const from) const
	Same as coordinatesOfFrom(), but with `qreal` parameters. More...

Coordinate system transformation of vectors
Vec	transformOf (const Vec &src) const
	Returns the Frame transform of a vector `src` defined in the world coordinate system (converts vectors from world to Frame). More...

Vec	inverseTransformOf (const Vec &src) const
	Returns the world transform of the vector whose coordinates in the Frame coordinate system is `src` (converts vectors from Frame to world). More...

Vec	localTransformOf (const Vec &src) const
	Returns the Frame transform of a vector `src` defined in the referenceFrame() coordinate system (converts vectors from referenceFrame() to Frame). More...

Vec	localInverseTransformOf (const Vec &src) const
	Returns the referenceFrame() transform of a vector `src` defined in the Frame coordinate system (converts vectors from Frame to referenceFrame()). More...

Vec	transformOfIn (const Vec &src, const Frame *const in) const
	Returns the `in` transform of the vector whose coordinates in the Frame coordinate system is `src` (converts vectors from Frame to `in`). More...

Vec	transformOfFrom (const Vec &src, const Frame *const from) const
	Returns the Frame transform of the vector whose coordinates in the `from` coordinate system is `src` (converts vectors from `from` to Frame). More...

void	getTransformOf (const qreal src[3], qreal res[3]) const
	Same as transformOf(), but with `qreal` parameters. More...

void	getInverseTransformOf (const qreal src[3], qreal res[3]) const
	Same as inverseTransformOf(), but with `qreal` parameters. More...

void	getLocalTransformOf (const qreal src[3], qreal res[3]) const
	Same as localTransformOf(), but with `qreal` parameters. More...

void	getLocalInverseTransformOf (const qreal src[3], qreal res[3]) const
	Same as localInverseTransformOf(), but with `qreal` parameters. More...

void	getTransformOfIn (const qreal src[3], qreal res[3], const Frame *const in) const
	Same as transformOfIn(), but with `qreal` parameters. More...

void	getTransformOfFrom (const qreal src[3], qreal res[3], const Frame *const from) const
	Same as transformOfFrom(), but with `qreal` parameters. More...

Constraint on the displacement
Constraint *	constraint () const
	Returns the current constraint applied to the Frame. More...

void	setConstraint (Constraint *const constraint)
	Sets the constraint() attached to the Frame. More...

Associated matrices
const GLdouble *	matrix () const
	Returns the 4x4 OpenGL transformation matrix represented by the Frame. More...

void	getMatrix (GLdouble m[4][4]) const
	`GLdouble`[4][4] version of matrix(). More...

void	getMatrix (GLdouble m[16]) const
	`GLdouble`[16] version of matrix(). More...

const GLdouble *	worldMatrix () const
	Returns the 4x4 OpenGL transformation matrix represented by the Frame. More...

void	getWorldMatrix (GLdouble m[4][4]) const
	qreal[4][4] parameter version of worldMatrix(). More...

void	getWorldMatrix (GLdouble m[16]) const
	qreal[16] parameter version of worldMatrix(). More...

void	setFromMatrix (const GLdouble m[4][4])
	This is an overloaded method provided for convenience. More...

void	setFromMatrix (const GLdouble m[16])
	Sets the Frame from an OpenGL matrix representation (rotation in the upper left 3x3 matrix and translation on the last line). More...

Inversion of the transformation
Frame	inverse () const
	Returns a Frame representing the inverse of the Frame space transformation. More...

Frame	worldInverse () const
	Returns the inverse() of the Frame world transformation. More...

Constructor details

◆ Frame() [1/3]

Frame::Frame ( )

Creates a default Frame.

Its position() is (0,0,0) and it has an identity orientation() Quaternion. The referenceFrame() and the constraint() are nullptr.

◆ ~Frame()

virtual qglviewer::Frame::~Frame ( )

inlinevirtual

Virtual destructor.

Empty.

◆ Frame() [2/3]

Frame::Frame ( const Frame & frame )

Copy constructor.

The translation() and rotation() as well as constraint() and referenceFrame() pointers are copied.

◆ Frame() [3/3]

Frame::Frame	(	const Vec &	position,
		const Quaternion &	orientation
	)

Creates a Frame with a position() and an orientation().

See the Vec and Quaternion documentations for convenient constructors and methods.

The Frame is defined in the world coordinate system (its referenceFrame() is nullptr). It has a nullptr associated constraint().

Function details

◆ alignWithFrame()

void Frame::alignWithFrame	(	const Frame *const	frame,
		bool	move = `false`,
		qreal	threshold = `0.0`
	)

Aligns the Frame with frame, so that two of their axis are parallel.

If one of the X, Y and Z axis of the Frame is almost parallel to any of the X, Y, or Z axis of frame, the Frame is rotated so that these two axis actually become parallel.

If, after this first rotation, two other axis are also almost parallel, a second alignment is performed. The two frames then have identical orientations, up to 90 degrees rotations.

threshold measures how close two axis must be to be considered parallel. It is compared with the absolute values of the dot product of the normalized axis. As a result, useful range is sqrt(2)/2 (systematic alignment) to 1 (no alignment).

When move is set to true, the Frame position() is also affected by the alignment. The new Frame's position() is such that the frame position (computed with coordinatesOf(), in the Frame coordinates system) does not change.

frame may be nullptr and then represents the world coordinate system (same convention than for the referenceFrame()).

The rotation (and translation when move is true) applied to the Frame are filtered by the possible constraint().

◆ constraint()

Constraint* qglviewer::Frame::constraint ( ) const

inline

Returns the current constraint applied to the Frame.

A nullptr value (default) means that no Constraint is used to filter Frame translation and rotation. See the Constraint class documentation for details.

You may have to use a dynamic_cast to convert the result to a Constraint derived class.

◆ coordinatesOf()

Vec Frame::coordinatesOf ( const Vec & src ) const

Returns the Frame coordinates of a point src defined in the world coordinate system (converts from world to Frame).

inverseCoordinatesOf() performs the inverse convertion. transformOf() converts 3D vectors instead of 3D coordinates.

See the frameTransform example for an illustration.

◆ coordinatesOfFrom()

Vec Frame::coordinatesOfFrom	(	const Vec &	src,
		const Frame *const	from
	)		const

Returns the Frame coordinates of the point whose position in the from coordinate system is src (converts from from to Frame).

coordinatesOfIn() performs the inverse transformation.

◆ coordinatesOfIn()

Vec Frame::coordinatesOfIn	(	const Vec &	src,
		const Frame *const	in
	)		const

Returns the in coordinates of the point whose position in the Frame coordinate system is src (converts from Frame to in).

coordinatesOfFrom() performs the inverse transformation.

◆ domElement()

QDomElement Frame::domElement	(	const QString &	name,
		QDomDocument &	document
	)		const

virtual

Returns an XML QDomElement that represents the Frame.

name is the name of the QDomElement tag. doc is the QDomDocument factory used to create QDomElement.

The resulting QDomElement looks like:

<name>
  <position x=".." y=".." z=".." />
  <orientation q0=".." q1=".." q2=".." q3=".." />
</name>

Use initFromDOMElement() to restore the Frame state from the resulting QDomElement.

See Vec::domElement() for a complete example. See also Quaternion::domElement(), Camera::domElement()...

Attention: The constraint() and referenceFrame() are not saved in the QDomElement.

Reimplemented in qglviewer::ManipulatedFrame, and qglviewer::ManipulatedCameraFrame.

◆ getCoordinatesOf()

void Frame::getCoordinatesOf	(	const qreal	src[3],
		qreal	res[3]
	)		const

Same as coordinatesOf(), but with qreal parameters.

◆ getCoordinatesOfFrom()

void Frame::getCoordinatesOfFrom	(	const qreal	src[3],
		qreal	res[3],
		const Frame *const	from
	)		const

Same as coordinatesOfFrom(), but with qreal parameters.

◆ getCoordinatesOfIn()

void Frame::getCoordinatesOfIn	(	const qreal	src[3],
		qreal	res[3],
		const Frame *const	in
	)		const

Same as coordinatesOfIn(), but with qreal parameters.

◆ getInverseCoordinatesOf()

void Frame::getInverseCoordinatesOf	(	const qreal	src[3],
		qreal	res[3]
	)		const

Same as inverseCoordinatesOf(), but with qreal parameters.

◆ getInverseTransformOf()

void Frame::getInverseTransformOf	(	const qreal	src[3],
		qreal	res[3]
	)		const

Same as inverseTransformOf(), but with qreal parameters.

◆ getLocalCoordinatesOf()

void Frame::getLocalCoordinatesOf	(	const qreal	src[3],
		qreal	res[3]
	)		const

Same as localCoordinatesOf(), but with qreal parameters.

◆ getLocalInverseCoordinatesOf()

void Frame::getLocalInverseCoordinatesOf	(	const qreal	src[3],
		qreal	res[3]
	)		const

Same as localInverseCoordinatesOf(), but with qreal parameters.

◆ getLocalInverseTransformOf()

void Frame::getLocalInverseTransformOf	(	const qreal	src[3],
		qreal	res[3]
	)		const

Same as localInverseTransformOf(), but with qreal parameters.

◆ getLocalTransformOf()

void Frame::getLocalTransformOf	(	const qreal	src[3],
		qreal	res[3]
	)		const

Same as localTransformOf(), but with qreal parameters.

◆ getMatrix() [1/2]

void Frame::getMatrix ( GLdouble m[16] ) const

GLdouble[16] version of matrix().

◆ getMatrix() [2/2]

void Frame::getMatrix ( GLdouble m[4][4] ) const

GLdouble[4][4] version of matrix().

◆ getOrientation()

void Frame::getOrientation	(	qreal &	q0,
		qreal &	q1,
		qreal &	q2,
		qreal &	q3
	)		const

Get the current orientation of the frame (same as orientation()).

Parameters are the orientation Quaternion values. See also setOrientation().

The q are set to the orientation() of the Frame.

See Quaternion::Quaternion(qreal, qreal, qreal, qreal) for details on q.

◆ getPosition()

void Frame::getPosition	(	qreal &	x,
		qreal &	y,
		qreal &	z
	)		const

x, y and z are set to the position() of the Frame.

◆ getRotation()

void Frame::getRotation	(	qreal &	q0,
		qreal &	q1,
		qreal &	q2,
		qreal &	q3
	)		const

The q are set to the rotation() of the Frame.

See Quaternion::Quaternion(qreal, qreal, qreal, qreal) for details on q.

◆ getTransformOf()

void Frame::getTransformOf	(	const qreal	src[3],
		qreal	res[3]
	)		const

Same as transformOf(), but with qreal parameters.

◆ getTransformOfFrom()

void Frame::getTransformOfFrom	(	const qreal	src[3],
		qreal	res[3],
		const Frame *const	from
	)		const

Same as transformOfFrom(), but with qreal parameters.

◆ getTransformOfIn()

void Frame::getTransformOfIn	(	const qreal	src[3],
		qreal	res[3],
		const Frame *const	in
	)		const

Same as transformOfIn(), but with qreal parameters.

◆ getTranslation()

void Frame::getTranslation	(	qreal &	x,
		qreal &	y,
		qreal &	z
	)		const

Fill x, y and z with the translation() of the Frame.

◆ getWorldMatrix() [1/2]

void Frame::getWorldMatrix ( GLdouble m[16] ) const

qreal[16] parameter version of worldMatrix().

◆ getWorldMatrix() [2/2]

void Frame::getWorldMatrix ( GLdouble m[4][4] ) const

qreal[4][4] parameter version of worldMatrix().

◆ initFromDOMElement

void Frame::initFromDOMElement ( const QDomElement & element )

virtualslot

Restores the Frame state from a QDomElement created by domElement().

See domElement() for the QDomElement syntax. See the Vec::initFromDOMElement() and Quaternion::initFromDOMElement() documentations for details on default values if an argument is missing.

Attention: The constraint() and referenceFrame() are not restored by this method and are left unchanged.

◆ interpolated

void qglviewer::Frame::interpolated ( )

signal

This signal is emitted when the Frame is interpolated by a KeyFrameInterpolator.

See the KeyFrameInterpolator documentation for details.

If a KeyFrameInterpolator is used to successively interpolate several Frames in your scene, connect the KeyFrameInterpolator::interpolated() signal instead (identical, but independent of the interpolated Frame).

◆ inverse()

Frame Frame::inverse ( ) const

Returns a Frame representing the inverse of the Frame space transformation.

The rotation() of the new Frame is the Quaternion::inverse() of the original rotation. Its translation() is the negated inverse rotated image of the original translation.

If a Frame is considered as a space rigid transformation (translation and rotation), the inverse() Frame performs the inverse transformation.

Only the local Frame transformation (i.e. defined with respect to the referenceFrame()) is inverted. Use worldInverse() for a global inverse.

The resulting Frame has the same referenceFrame() as the Frame and a nullptr constraint().

Note: The scaling factor of the 4x4 matrix is 1.0.

◆ inverseCoordinatesOf()

Vec Frame::inverseCoordinatesOf ( const Vec & src ) const

Returns the world coordinates of the point whose position in the Frame coordinate system is src (converts from Frame to world).

coordinatesOf() performs the inverse convertion. Use inverseTransformOf() to transform 3D vectors instead of 3D coordinates.

◆ inverseTransformOf()

Vec Frame::inverseTransformOf ( const Vec & src ) const

Returns the world transform of the vector whose coordinates in the Frame coordinate system is src (converts vectors from Frame to world).

transformOf() performs the inverse transformation. Use inverseCoordinatesOf() to transform 3D coordinates instead of 3D vectors.

◆ localCoordinatesOf()

Vec Frame::localCoordinatesOf ( const Vec & src ) const

Returns the Frame coordinates of a point src defined in the referenceFrame() coordinate system (converts from referenceFrame() to Frame).

localInverseCoordinatesOf() performs the inverse convertion. See also localTransformOf().

◆ localInverseCoordinatesOf()

Vec Frame::localInverseCoordinatesOf ( const Vec & src ) const

Returns the referenceFrame() coordinates of a point src defined in the Frame coordinate system (converts from Frame to referenceFrame()).

localCoordinatesOf() performs the inverse convertion. See also localInverseTransformOf().

◆ localInverseTransformOf()

Vec Frame::localInverseTransformOf ( const Vec & src ) const

Returns the referenceFrame() transform of a vector src defined in the Frame coordinate system (converts vectors from Frame to referenceFrame()).

localTransformOf() performs the inverse transformation. See also localInverseCoordinatesOf().

◆ localTransformOf()

Vec Frame::localTransformOf ( const Vec & src ) const

Returns the Frame transform of a vector src defined in the referenceFrame() coordinate system (converts vectors from referenceFrame() to Frame).

localInverseTransformOf() performs the inverse transformation. See also localCoordinatesOf().

◆ matrix()

const GLdouble * Frame::matrix ( ) const

Returns the 4x4 OpenGL transformation matrix represented by the Frame.

This method should be used in conjunction with glMultMatrixd() to modify the OpenGL modelview matrix from a Frame hierarchy. With this Frame hierarchy:

Frame* body     = new Frame();
Frame* leftArm  = new Frame();
Frame* rightArm = new Frame();
leftArm->setReferenceFrame(body);
rightArm->setReferenceFrame(body);

The associated OpenGL drawing code should look like:

void Viewer::draw()
{
      glPushMatrix();
      glMultMatrixd(body->matrix());
      drawBody();
 
      glPushMatrix();
      glMultMatrixd(leftArm->matrix());
      drawArm();
      glPopMatrix();
 
      glPushMatrix();
      glMultMatrixd(rightArm->matrix());
      drawArm();
      glPopMatrix();
 
      glPopMatrix();
}

Note the use of nested glPushMatrix() and glPopMatrix() blocks to represent the frame hierarchy: leftArm and rightArm are both correctly drawn with respect to the body coordinate system.

This matrix only represents the local Frame transformation (i.e. with respect to the referenceFrame()). Use worldMatrix() to get the full Frame transformation matrix (i.e. from the world to the Frame coordinate system). These two match when the referenceFrame() is nullptr.

The result is only valid until the next call to matrix(), getMatrix(), worldMatrix() or getWorldMatrix(). Use it immediately (as above) or use getMatrix() instead.

Attention: The OpenGL format of the result is the transpose of the actual mathematical European representation (translation is on the last line instead of the last column).

Note: The scaling factor of the 4x4 matrix is 1.0.

◆ modified

void qglviewer::Frame::modified ( )

signal

This signal is emitted whenever the position() or the orientation() of the Frame is modified.

Connect this signal to any object that must be notified:

QObject::connect(myFrame, SIGNAL(modified()), myObject, SLOT(update()));

qglviewer::Frame::modified

void modified()

This signal is emitted whenever the position() or the orientation() of the Frame is modified.

Use the QGLViewer::QGLViewerPool() to connect the signal to all the viewers.

Note: If your Frame is part of a Frame hierarchy (see referenceFrame()), a modification of one of the parents of this Frame will not emit this signal. Use code like this to change this behavior (you can do this recursively for all the referenceFrame() until the nullptr world root frame is encountered):
// Emits the Frame modified() signal when its referenceFrame() is modified().

connect(myFrame->referenceFrame(), SIGNAL(modified()), myFrame,

SIGNAL(modified()));

Attention: Connecting this signal to a QOpenGLWidget::update() slot (or a method that calls it) will prevent you from modifying the Frame inside your QGLViewer::draw() method as it would result in an infinite loop. However, QGLViewer::draw() should not modify the scene.

Note: Note that this signal might be emitted even if the Frame is not actually modified, for instance after a translate(Vec(0,0,0)) or a setPosition(position()).

◆ operator=()

Frame & Frame::operator= ( const Frame & frame )

Equal operator.

The referenceFrame() and constraint() pointers are copied.

Attention: Signal and slot connections are not copied.

◆ orientation()

Quaternion Frame::orientation ( ) const

Returns the orientation of the Frame, defined in the world coordinate system.

See also position(), setOrientation() and rotation().

◆ position()

Vec Frame::position ( ) const

Returns the position of the Frame, defined in the world coordinate system.

See also orientation(), setPosition() and translation().

◆ projectOnLine()

void Frame::projectOnLine	(	const Vec &	origin,
		const Vec &	direction
	)

Translates the Frame so that its position() lies on the line defined by origin and direction (defined in the world coordinate system).

Simply uses an orthogonal projection. direction does not need to be normalized.

◆ referenceFrame()

const Frame* qglviewer::Frame::referenceFrame ( ) const

inline

Returns the reference Frame, in which coordinates system the Frame is defined.

The translation() and rotation() of the Frame are defined with respect to the referenceFrame() coordinate system. A nullptr referenceFrame() (default value) means that the Frame is defined in the world coordinate system.

Use position() and orientation() to recursively convert values along the referenceFrame() chain and to get values expressed in the world coordinate system. The values match when the referenceFrame() is nullptr.

Use setReferenceFrame() to set this value and create a Frame hierarchy. Convenient functions allow you to convert 3D coordinates from one Frame to an other: see coordinatesOf(), localCoordinatesOf(), coordinatesOfIn() and their inverse functions.

Vectors can also be converted using transformOf(), transformOfIn, localTransformOf() and their inverse functions.

◆ rotate() [1/4]

void Frame::rotate ( const Quaternion & q )

Rotates the Frame by q (defined in the Frame coordinate system): R = R*q.

The rotation actually applied to the Frame may differ from q since it can be filtered by the constraint(). Use rotate(Quaternion&) or setRotationWithConstraint() to retrieve the filtered rotation value. Use setRotation() to directly rotate the Frame without taking the constraint() into account.

See also translate(const Vec&). Emits the modified() signal.

◆ rotate() [2/4]

void Frame::rotate	(	qreal &	q0,
		qreal &	q1,
		qreal &	q2,
		qreal &	q3
	)

Same as rotate(Quaternion&) but with qreal Quaternion parameters.

◆ rotate() [3/4]

void Frame::rotate	(	qreal	q0,
		qreal	q1,
		qreal	q2,
		qreal	q3
	)

Same as rotate(const Quaternion&) but with qreal Quaternion parameters.

◆ rotate() [4/4]

void Frame::rotate ( Quaternion & q )

Same as rotate(const Quaternion&) but q may be modified to satisfy the rotation constraint().

Its new value corresponds to the rotation that has actually been applied to the Frame.

◆ rotateAroundPoint() [1/2]

void Frame::rotateAroundPoint	(	const Quaternion &	rotation,
		const Vec &	point
	)

Same as rotateAroundPoint(), but with a const rotation Quaternion.

Note that the actual rotation may differ since it can be filtered by the constraint().

◆ rotateAroundPoint() [2/2]

void Frame::rotateAroundPoint	(	Quaternion &	rotation,
		const Vec &	point
	)

Makes the Frame rotate() by rotation around point.

point is defined in the world coordinate system, while the rotation axis is defined in the Frame coordinate system.

If the Frame has a constraint(), rotation is first constrained using Constraint::constrainRotation(). The translation which results from the filtered rotation around point is then computed and filtered using Constraint::constrainTranslation(). The new rotation value corresponds to the rotation that has actually been applied to the Frame.

Emits the modified() signal.

◆ rotation()

Quaternion qglviewer::Frame::rotation ( ) const

inline

Returns the Frame rotation, defined with respect to the referenceFrame().

Use orientation() to get the result in the world coordinates. These two values are identical when the referenceFrame() is nullptr (default).

Returns the current Quaternion orientation. See setRotation().

◆ setConstraint()

void qglviewer::Frame::setConstraint ( Constraint *const constraint )

inline

Sets the constraint() attached to the Frame.

A nullptr value means no constraint. The previous constraint() should be deleted by the calling method if needed.

◆ setFromMatrix() [1/2]

void Frame::setFromMatrix ( const GLdouble m[16] )

Sets the Frame from an OpenGL matrix representation (rotation in the upper left 3x3 matrix and translation on the last line).

Hence, if a code fragment looks like:

GLdouble m[16]={...};

glMultMatrixd(m);

It is equivalent to write:

Frame fr;
fr.setFromMatrix(m);
glMultMatrixd(fr.matrix());

Using this conversion, you can benefit from the powerful Frame transformation methods to translate points and vectors to and from the Frame coordinate system to any other Frame coordinate system (including the world coordinate system). See coordinatesOf() and transformOf().

Emits the modified() signal. See also matrix(), getMatrix() and Quaternion::setFromRotationMatrix().

Attention: A Frame does not contain a scale factor. The possible scaling in m will not be converted into the Frame by this method.

◆ setFromMatrix() [2/2]

void Frame::setFromMatrix ( const GLdouble m[4][4] )

This is an overloaded method provided for convenience.

Same as setFromMatrix().

◆ setOrientation() [1/2]

void Frame::setOrientation ( const Quaternion & orientation )

Sets the orientation() of the Frame, defined in the world coordinate system.

Emits the modified() signal.

Use setRotation() to define the local frame rotation (with respect to the referenceFrame()). The potential constraint() of the Frame is not taken into account, use setOrientationWithConstraint() instead.

◆ setOrientation() [2/2]

void Frame::setOrientation	(	qreal	q0,
		qreal	q1,
		qreal	q2,
		qreal	q3
	)

Same as setOrientation(), but with qreal parameters.

◆ setOrientationWithConstraint()

void Frame::setOrientationWithConstraint ( Quaternion & orientation )

Same as setOrientation(), but orientation is modified so that the potential constraint() of the Frame is satisfied.

◆ setPosition() [1/2]

void Frame::setPosition ( const Vec & position )

Sets the position() of the Frame, defined in the world coordinate system.

Emits the modified() signal.

Use setTranslation() to define the local frame translation (with respect to the referenceFrame()). The potential constraint() of the Frame is not taken into account, use setPositionWithConstraint() instead.

◆ setPosition() [2/2]

void Frame::setPosition	(	qreal	x,
		qreal	y,
		qreal	z
	)

Same as setPosition(), but with qreal parameters.

◆ setPositionAndOrientation()

void Frame::setPositionAndOrientation	(	const Vec &	position,
		const Quaternion &	orientation
	)

Same as successive calls to setPosition() and then setOrientation().

Only one modified() signal is emitted, which is convenient if this signal is connected to a QGLViewer::update() slot. See also setTranslationAndRotation() and setPositionAndOrientationWithConstraint().

◆ setPositionAndOrientationWithConstraint()

void Frame::setPositionAndOrientationWithConstraint	(	Vec &	position,
		Quaternion &	orientation
	)

Same as setPositionAndOrientation() but position and orientation are modified to satisfy the constraint.

Emits the modified() signal.

◆ setPositionWithConstraint()

void Frame::setPositionWithConstraint ( Vec & position )

Same as setPosition(), but position is modified so that the potential constraint() of the Frame is satisfied.

◆ setReferenceFrame()

void Frame::setReferenceFrame ( const Frame *const refFrame )

Sets the referenceFrame() of the Frame.

The Frame translation() and rotation() are then defined in the referenceFrame() coordinate system. Use position() and orientation() to express these in the world coordinate system.

Emits the modified() signal if refFrame differs from the current referenceFrame().

Using this method, you can create a hierarchy of Frames. This hierarchy needs to be a tree, which root is the world coordinate system (i.e. a nullptr referenceFrame()). A warning is printed and no action is performed if setting refFrame as the referenceFrame() would create a loop in the Frame hierarchy (see settingAsReferenceFrameWillCreateALoop()).

◆ setRotation() [1/2]

void qglviewer::Frame::setRotation ( const Quaternion & rotation )

inline

Set the current rotation Quaternion.

See rotation() and the different Quaternion constructors. Emits the modified() signal. See also setTranslation() and setRotationWithConstraint().

Sets the rotation() of the Frame, locally defined with respect to the referenceFrame(). Emits the modified() signal.

Use setOrientation() to define the world coordinates orientation(). The potential constraint() of the Frame is not taken into account, use setRotationWithConstraint() instead.

◆ setRotation() [2/2]

void Frame::setRotation	(	qreal	q0,
		qreal	q1,
		qreal	q2,
		qreal	q3
	)

Same as setRotation() but with qreal Quaternion parameters.

◆ setRotationWithConstraint()

void Frame::setRotationWithConstraint ( Quaternion & rotation )

Same as setRotation(), but rotation is modified so that the potential constraint() of the Frame is satisfied.

Emits the modified() signal. See also setTranslationWithConstraint() and setOrientationWithConstraint().

◆ settingAsReferenceFrameWillCreateALoop()

bool Frame::settingAsReferenceFrameWillCreateALoop ( const Frame *const frame )

Returns true if setting frame as the Frame's referenceFrame() would create a loop in the Frame hierarchy.

◆ setTranslation() [1/2]

void qglviewer::Frame::setTranslation ( const Vec & translation )

inline

Sets the translation() of the frame, locally defined with respect to the referenceFrame().

Emits the modified() signal.

Use setPosition() to define the world coordinates position(). Use setTranslationWithConstraint() to take into account the potential constraint() of the Frame.

◆ setTranslation() [2/2]

void Frame::setTranslation	(	qreal	x,
		qreal	y,
		qreal	z
	)

Same as setTranslation(), but with qreal parameters.

◆ setTranslationAndRotation()

void Frame::setTranslationAndRotation	(	const Vec &	translation,
		const Quaternion &	rotation
	)

Same as successive calls to setTranslation() and then setRotation().

Only one modified() signal is emitted, which is convenient if this signal is connected to a QGLViewer::update() slot. See also setPositionAndOrientation() and setTranslationAndRotationWithConstraint().

◆ setTranslationAndRotationWithConstraint()

void Frame::setTranslationAndRotationWithConstraint	(	Vec &	translation,
		Quaternion &	rotation
	)

Same as setTranslationAndRotation(), but translation and orientation are modified to satisfy the constraint().

Emits the modified() signal.

◆ setTranslationWithConstraint()

void Frame::setTranslationWithConstraint ( Vec & translation )

Same as setTranslation(), but translation is modified so that the potential constraint() of the Frame is satisfied.

Emits the modified() signal. See also setRotationWithConstraint() and setPositionWithConstraint().

◆ transformOf()

Vec Frame::transformOf ( const Vec & src ) const

Returns the Frame transform of a vector src defined in the world coordinate system (converts vectors from world to Frame).

inverseTransformOf() performs the inverse transformation. coordinatesOf() converts 3D coordinates instead of 3D vectors (here only the rotational part of the transformation is taken into account).

See the frameTransform example for an illustration.

◆ transformOfFrom()

Vec Frame::transformOfFrom	(	const Vec &	src,
		const Frame *const	from
	)		const

Returns the Frame transform of the vector whose coordinates in the from coordinate system is src (converts vectors from from to Frame).

transformOfIn() performs the inverse transformation.

◆ transformOfIn()

Vec Frame::transformOfIn	(	const Vec &	src,
		const Frame *const	in
	)		const

Returns the in transform of the vector whose coordinates in the Frame coordinate system is src (converts vectors from Frame to in).

transformOfFrom() performs the inverse transformation.

◆ translate() [1/4]

void Frame::translate ( const Vec & t )

Translates the Frame of t (defined in the Frame coordinate system).

The translation actually applied to the Frame may differ from t since it can be filtered by the constraint(). Use translate(Vec&) or setTranslationWithConstraint() to retrieve the filtered translation value. Use setTranslation() to directly translate the Frame without taking the constraint() into account.

See also rotate(const Quaternion&). Emits the modified() signal.

◆ translate() [2/4]

void Frame::translate	(	qreal &	x,
		qreal &	y,
		qreal &	z
	)

Same as translate(Vec&) but with qreal parameters.

◆ translate() [3/4]

void Frame::translate	(	qreal	x,
		qreal	y,
		qreal	z
	)

Same as translate(const Vec&) but with qreal parameters.

◆ translate() [4/4]

void Frame::translate ( Vec & t )

Same as translate(const Vec&) but t may be modified to satisfy the translation constraint().

Its new value corresponds to the translation that has actually been applied to the Frame.

◆ translation()

Vec qglviewer::Frame::translation ( ) const

inline

Returns the Frame translation, defined with respect to the referenceFrame().

Use position() to get the result in the world coordinates. These two values are identical when the referenceFrame() is nullptr (default).

◆ worldInverse()

Frame qglviewer::Frame::worldInverse ( ) const

inline

Returns the inverse() of the Frame world transformation.

The orientation() of the new Frame is the Quaternion::inverse() of the original orientation. Its position() is the negated and inverse rotated image of the original position.

The result Frame has a nullptr referenceFrame() and a nullptr constraint().

Use inverse() for a local (i.e. with respect to referenceFrame()) transformation inverse.

◆ worldMatrix()

const GLdouble * Frame::worldMatrix ( ) const

Returns the 4x4 OpenGL transformation matrix represented by the Frame.

This method should be used in conjunction with glMultMatrixd() to modify the OpenGL modelview matrix from a Frame:

// The modelview here corresponds to the world coordinate system.
Frame fr(pos, Quaternion(from, to));
glPushMatrix();
glMultMatrixd(fr.worldMatrix());
// draw object in the fr coordinate system.
glPopMatrix();

This matrix represents the global Frame transformation: the entire referenceFrame() hierarchy is taken into account to define the Frame transformation from the world coordinate system. Use matrix() to get the local Frame transformation matrix (i.e. defined with respect to the referenceFrame()). These two match when the referenceFrame() is nullptr.

The OpenGL format of the result is the transpose of the actual mathematical European representation (translation is on the last line instead of the last column).

Attention: The result is only valid until the next call to matrix(), getMatrix(), worldMatrix() or getWorldMatrix(). Use it immediately (as above) or use getWorldMatrix() instead.

Note: The scaling factor of the 4x4 matrix is 1.0.

Detailed Description

Hierarchy of Frames

Constraints

Derived classes

Public Member Functions

Signals

XML representation

World coordinates position and orientation

Local translation and rotation w/r reference Frame

Frame hierarchy

Frame modification

Coordinate system transformation of 3D coordinates

Coordinate system transformation of vectors

Constraint on the displacement

Associated matrices

Inversion of the transformation

Constructor details

◆ Frame() [1/3]

◆ ~Frame()

◆ Frame() [2/3]

◆ Frame() [3/3]

Function details

◆ alignWithFrame()

◆ constraint()

◆ coordinatesOf()

◆ coordinatesOfFrom()

◆ coordinatesOfIn()

◆ domElement()

◆ getCoordinatesOf()

◆ getCoordinatesOfFrom()

◆ getCoordinatesOfIn()

◆ getInverseCoordinatesOf()

◆ getInverseTransformOf()

◆ getLocalCoordinatesOf()

◆ getLocalInverseCoordinatesOf()

◆ getLocalInverseTransformOf()

◆ getLocalTransformOf()

◆ getMatrix() [1/2]

◆ getMatrix() [2/2]

◆ getOrientation()

◆ getPosition()

◆ getRotation()

◆ getTransformOf()

◆ getTransformOfFrom()

◆ getTransformOfIn()

◆ getTranslation()

◆ getWorldMatrix() [1/2]

◆ getWorldMatrix() [2/2]

◆ initFromDOMElement

◆ interpolated

◆ inverse()

◆ inverseCoordinatesOf()

◆ inverseTransformOf()

◆ localCoordinatesOf()

◆ localInverseCoordinatesOf()

◆ localInverseTransformOf()

◆ localTransformOf()

◆ matrix()

◆ modified

◆ operator=()

◆ orientation()

◆ position()

◆ projectOnLine()

◆ referenceFrame()

◆ rotate() [1/4]

◆ rotate() [2/4]

◆ rotate() [3/4]

◆ rotate() [4/4]

◆ rotateAroundPoint() [1/2]

◆ rotateAroundPoint() [2/2]

◆ rotation()

◆ setConstraint()

◆ setFromMatrix() [1/2]

◆ setFromMatrix() [2/2]

◆ setOrientation() [1/2]

◆ setOrientation() [2/2]

◆ setOrientationWithConstraint()

◆ setPosition() [1/2]

◆ setPosition() [2/2]

◆ setPositionAndOrientation()