Trackball class for manipulating a camera. More...

#include <trackball.hpp>

Inheritance diagram for Tucano::Trackball:

Public Member Functions
	Trackball (string shader_dir="")
	Default constructor. More...

void	reset (void)
	Resets trackball to initial position and orientation. More...

bool	isRotating (void)
	Returns wether the trackball is being rotated or not. More...

bool	isTranslating (void)
	Returns wether the trackball is being translated or not. More...

Eigen::Vector3f	getDefaultTranslation (void)
	Returns the default translation for placing the camera outside the trackball sphere. More...

void	setDefaultTranslation (Eigen::Vector3f t)
	Sets the default translation vector. More...

Eigen::Quaternion< float >	getDefaultRotation (void)
	Returns the default rotation quaternion. More...

virtual Eigen::Quaternion< float >	getRotation (void)
	Returns the rotation (without the default part) as a quaternion. More...

void	setDefaultRotation (Eigen::Matrix3f rot)
	Sets the default rotation quaternion. More...

virtual void	setRadius (float r)
	Sets the radius. More...

float	getZoom (void)
	Retuns the zoom factor (the radius of the trackball). More...

void	setTrackballProjectionMatrix (const Eigen::Matrix4f &mat)
	Sets the projection matrix used for the trackball rendering. Note that this is usually different than the projection matrix for the scene. More...

virtual void	endRotation (void)
	Indicates that a rotation has ended. Disables the rotating flag, indicating that the mouse callback functions will stop reading the mouse coordinates in order to stop the trackball's rotation. More...

void	endTranslation (void)
	Indicates that a translation has ended. Disable the translating flag, indicating that the mouse callback functions will stop reading the mouse coordinates in order to stop the trackball's translation. More...

void	setRenderFlag (bool flag)
	Returns wether the trackball representation should be drawn or not. More...

void	loadShader (void)
	Load Trackball Shader file. More...

void	initOpenGLMatrices (void)
	Initializes the view and projection matrices. They are all initialized as Identity matrices, but view is then translated by the default_translation vector. More...

Eigen::Matrix4f	setTrackballPerspectiveMatrix (float fy, float aspect_ratio, float near_plane, float far_plane)
	Sets the trackball projection matrix as perspective. More...

Eigen::Matrix4f	setTrackballOrthographicMatrix (float left, float right, float bottom, float top, float near_plane, float far_plane)
	Sets the trackball projection matrix as orthographic. More...

virtual Eigen::Quaternion< float >	computeRotationAngle (float sensibility=1.0)
	Computes the trackball's rotation, using stored initial and final position vectors. More...

virtual Eigen::Vector3f	computeTranslationVector (void)
	Compute the trackball's translation, using stored initial and final position vectors. More...

Eigen::Vector2f	normalizePosition (const Eigen::Vector2f &pos)
	Nomalizes a screen position to range [-1,1]. More...

virtual Eigen::Quaternion< float >	rotateCamera (const Eigen::Vector2f &pos)
	Computes and applies the rotation transformations to the trackball given new position. More...

virtual Eigen::Vector3f	translateCamera (const Eigen::Vector2f &pos)
	Computes and applies the translation transformations to the trackball given new position. More...

void	increaseZoom (float scale)
	Increases the zoom on the scene by appling a scale to the View Matrix. The current scale used in View Matrix is multiplied by the given scale factor. More...

void	decreaseZoom (float scale)
	Decreases the zoom on the scene by appling a scale to the View Matrix. The current scale used in View Matrix is divided by the given scale factor. More...

void	applyScaleToViewMatrix (float scale)
	Applies a scale factor to the viewMatrix. The current scale used in view matrix will be substituted by the given scale factor. More...

void	translateViewMatrix (const Eigen::Vector3f &translation)
	Translates the view matrix by a given vector trans. This directly modifies the translation vector of the trackball. Note that the view matrix is always recomputed using the translation, quaternion and zoom. More...

void	rotateViewMatrix (const Eigen::Affine3f &rot)
	Rotates the view matrix by a given rotation matrix. This directly modifies the quaternion of the trackball. Note that the view matrix is always recomputed using the translation, quaternion and zoom. More...

virtual void	updateViewMatrix (void)
	Applies all trackball's transformations to the view matrix. More...

void	createTrackballRepresentation (void)
	Creates the circle representating rotation around Z axis. The other circles will be created by simply rotating this one around the desired axis. More...

virtual void	render (Eigen::Affine3f ext_view_matrix=Eigen::Affine3f::Identity(), Eigen::Matrix4f ext_proj_matrix=Eigen::Matrix4f::Identity())
	Renders the trackball representation. More...

Public Member Functions inherited from Tucano::Camera
void	resetViewMatrix (void)
	Reset view matrix. More...

void	resetProjectionMatrix (void)
	Reset projection matrix. More...

void	reset (void)
	Resets trackball to initial position and orientation. More...

Eigen::Vector3f	getCenter (void) const
	Returns the center of the camera in world space. More...

void	getViewMatrix (GLdouble *matrix)
	Return the modelview matrix as a GLdouble array. More...

void	getProjectionMatrix (GLdouble *matrix)
	Return the projection matrix as a GLdouble array. More...

Eigen::Vector3f	projectPoint (const Eigen::Vector4f &pt, Eigen::Vector4f &viewport)
	Returns screen space coordinates of a 3D point. More...

Eigen::Affine3f	getViewMatrix (void) const
	Returns the view matrix as an Affine 3x3 matrix. More...

Eigen::Affine3f *	viewMatrix (void)
	Returns a pointer to the view matrix as an Affine 3x3 matrix. More...

Eigen::Matrix4f	getProjectionMatrix (void) const
	Returns the view matrix as an 4x4 matrix. More...

Eigen::Matrix4f *	projectionMatrix (void)
	Returns a pointer to the projection matrix as an 4x4 matrix. More...

Eigen::Matrix3f	getRotationMatrix (void) const
	Returns a 3x3 matrix containing only the rotation of the view matrix. More...

Eigen::Vector3f	getTranslationMatrix (void) const
	Returns the translation part of the view matrix as a vector. More...

float	getPerspectiveScale (void) const
	Returns the perspective scale. More...

Eigen::Vector4f	getViewport (void) const
	Returns the viewport coordinates. More...

Eigen::Vector2i	getViewportSize (void) const
	Returns the dimensions of the viewport. More...

float	getViewportAspectRatio (void) const
	Returns the viewport aspect ratio. More...

void	setViewport (const Eigen::Vector4f &vp)
	Sets the viewport coordinates. More...

void	setViewport (const Eigen::Vector2i &vp)

void	setViewport (const Eigen::Vector2f &vp)
	Sets the viewport coordinates considering that the minimum coordinates are zero. More...

void	setProjectionMatrix (const Eigen::Matrix4f &mat)
	Sets the projection matrix from a given 4x4 matrix. More...

void	setViewMatrix (const Eigen::Affine3f &mat)
	Sets the view matrix from a given an affine 3x3 matrix. More...

float	getNearPlane (void) const
	Returns near plane value. More...

float	getFarPlane (void) const
	Returns far plane value. More...

	~Camera ()
	Default destructor. More...

float	getFovy (void) const
	Returns current field of view angle in y axis. More...

	Camera (void)
	Default constructor. More...

Eigen::Matrix4f	setPerspectiveMatrix (float fy, float in_aspect_ratio, float in_near_plane, float in_far_plane)
	Sets the projection matrix as a perspective matrix. More...

void	changeFovy (float new_fovy)
	Changes the fovy and computes new perspective projection matrix. More...

Eigen::Matrix4f	setOrthographicMatrix (float left, float right, float bottom, float top, float near_plane, float far_plane)
	Sets the projection matrix as a orthographic matrix. More...

void	incrementFov (float inc)
	Increases the fov of the perspective matrix by a given increment. More...

void	translate (const Eigen::Vector3f &translation)
	Translates the view matrix by a given vector. More...

void	rotate (const Eigen::Quaternion< float > &rotation)
	Rotate the view matrix by a given quaternion. More...

void	scale (const Eigen::Vector3f &scale_factors)
	Scales the view matrix by given factors. More...

void	scale (float scale_factor)
	Scales the view matrix by given factor in all axis. More...

Protected Attributes
float	zoom = 1.0
	The current scale being applied to the View Matrix. More...

bool	rotating = false
	Flag that indicates wether the trackball is being rotated. More...

bool	translating = false
	Flag that indicates wether the trackball is being translated. More...

bool	drawTrackball = true
	Flag that indicates wether the trackball's representation should be drawn. More...

Eigen::Matrix4f	trackballProjectionMatrix
	Projection matrix used for the trackball's drawing. By default it is defined as an orthogonal projection matrix. More...

Eigen::Vector3f	initialPosition
	Initial position vector used to calculate trackball's rotation. More...

Eigen::Vector3f	finalPosition
	Final position vector used to calculate trackball's rotation. More...

Eigen::Vector2f	initialTranslationPosition
	Initial position vector used to calculate trackball's translation. More...

Eigen::Vector2f	finalTranslationPosition
	Final position vector used to calculate trackball's translation. More...

Eigen::Quaternion< float >	quaternion
	Trackball's quaternion. More...

Eigen::Quaternion< float >	default_quaternion
	Trackball's default rotation. More...

Eigen::Vector3f	translationVector
	Trackball's translation vector. More...

Eigen::Vector3f	default_translation = Eigen::Vector3f (0.0, 0.0, -4.0)
	Default translation to move camera away from center. More...

Tucano::Shader	trackball_shader
	Trackball Shader, used just for rendering the trackball's representation. More...

Tucano::Mesh	mesh
	Trackball visual representation. More...

float	radius = 0.8
	The trackball radius. It's defined as 0.8 times the smallest viewport dimension. More...

bool	use_default_shaders
	Flag to use default shaders set as const strings in class, or pass a directory with custom shaders. More...

Protected Attributes inherited from Tucano::Camera
Eigen::Matrix4f	projection_matrix
	Projection, or intrinsic, matrix. More...

Eigen::Affine3f	view_matrix
	View, or extrinsic, matrix. More...

Eigen::Vector4f	viewport
	Viewport dimensions [minX, minY, width, height]. More...

Eigen::Affine3f	default_view

float	near_plane
	Near plane used for projection matrix. More...

float	far_plane
	Far plane used for projection matrix. More...

float	frustum_left
	Frustum left dimension. More...

float	frustum_right
	Frustum right dimension. More...

float	frustum_top
	Frustum top dimension. More...

float	frustum_bottom
	Frustum bottom dimension. More...

float	aspect_ratio
	Aspect ratio for projection matrix. More...

float	focal_length
	Camera's Focal Length. More...

float	fovy
	Field of view angle in y axis. More...

bool	use_perspective
	Flag to indicate if using a perspective or othograpic projection. More...

Private Member Functions
virtual Eigen::Vector3f	computeSpherePosition (const Eigen::Vector2f &pos)
	Computes 3d coordinates on sphere from 2d position. More...

Additional Inherited Members
Static Public Member Functions inherited from Tucano::Camera
static Eigen::Matrix4f	createPerspectiveMatrix (float fy, float in_aspect_ratio, float in_near_plane, float in_far_plane)
	Returns a perspective projection matrix with the given parameters. More...

static Eigen::Matrix4f	createOrthographicMatrix (float left, float right, float bottom, float top, float near_plane, float far_plane)
	Returns an orthographic projection matrix with the given parameters. More...

Detailed Description

Trackball class for manipulating a camera.

This class simulates a standard trackball manipulation. The visual representation is a sphere with radius equal to 0.8 centered in the middle of the window (represented by the equation: x^2 + y^2 + z^2 = r^2), nested in an hyperbolic sheet opening (represented by the equation: z = (r^2/2)/sqrt(x^2+y^2). It is usually used for camera and light manipulation. It's important to notice that the x and y mouse coordinates passed to the trackball must be ranging from (-1,-1), being the lower left corner of screen, to (1,1) being the higher right corner. This means the coordinate system is centered in screen and normalized. Also, the view matrix is by default translated by the vector [0,0,-2], in order to remove the camera from the center of the world.

Constructor & Destructor Documentation

Tucano::Trackball::Trackball ( string shader_dir = "" )

inline

Default constructor.

Parameters

shader_dir Given directory containing trackball shaders, optional, otherwise uses default shaders.

Member Function Documentation

void Tucano::Trackball::applyScaleToViewMatrix ( float scale )

inline

Applies a scale factor to the viewMatrix. The current scale used in view matrix will be substituted by the given scale factor.

Parameters

scale The new scale factor to be applied to View Matrix.

virtual Eigen::Quaternion<float> Tucano::Trackball::computeRotationAngle ( float sensibility = 1.0 )

inlinevirtual

Computes the trackball's rotation, using stored initial and final position vectors.

Parameters

sensibility Scales the rotation, works as a sensibility factor

Returns: Returns the increment rotation

Reimplemented in Tucano::RotationManipulator, and Tucano::DirectionalTrackball.

virtual Eigen::Vector3f Tucano::Trackball::computeSpherePosition ( const Eigen::Vector2f & pos )

inlineprivatevirtual

Computes 3d coordinates on sphere from 2d position.

Parameters

pos	Given 2d screen position.

virtual Eigen::Vector3f Tucano::Trackball::computeTranslationVector ( void )

inlinevirtual

Compute the trackball's translation, using stored initial and final position vectors.

Reimplemented in Tucano::RotationManipulator, and Tucano::TranslationManipulator.

void Tucano::Trackball::createTrackballRepresentation ( void )

inline

Creates the circle representating rotation around Z axis. The other circles will be created by simply rotating this one around the desired axis.

void Tucano::Trackball::decreaseZoom ( float scale )

inline

Decreases the zoom on the scene by appling a scale to the View Matrix. The current scale used in View Matrix is divided by the given scale factor.

Parameters

scale The given scale factor, to which the current scale factor will be divided by.

virtual void Tucano::Trackball::endRotation ( void )

inlinevirtual

Indicates that a rotation has ended. Disables the rotating flag, indicating that the mouse callback functions will stop reading the mouse coordinates in order to stop the trackball's rotation.

Reimplemented in Tucano::RotationManipulator.

void Tucano::Trackball::endTranslation ( void )

inline

Indicates that a translation has ended. Disable the translating flag, indicating that the mouse callback functions will stop reading the mouse coordinates in order to stop the trackball's translation.

Eigen::Quaternion<float> Tucano::Trackball::getDefaultRotation ( void )

inline

Returns the default rotation quaternion.

Returns: Default rotation quaternion

Eigen::Vector3f Tucano::Trackball::getDefaultTranslation ( void )

inline

Returns the default translation for placing the camera outside the trackball sphere.

Returns: The default translation vector for the view matrix

virtual Eigen::Quaternion<float> Tucano::Trackball::getRotation ( void )

inlinevirtual

Returns the rotation (without the default part) as a quaternion.

Returns: Rotation as quaternion

float Tucano::Trackball::getZoom ( void )

inline

Retuns the zoom factor (the radius of the trackball).

Returns: Zoom factor.

void Tucano::Trackball::increaseZoom ( float scale )

inline

Increases the zoom on the scene by appling a scale to the View Matrix. The current scale used in View Matrix is multiplied by the given scale factor.

Parameters

scale The given scale to be multiplied by current scale factor.

void Tucano::Trackball::initOpenGLMatrices ( void )

inline

Initializes the view and projection matrices. They are all initialized as Identity matrices, but view is then translated by the default_translation vector.

bool Tucano::Trackball::isRotating ( void )

inline

Returns wether the trackball is being rotated or not.

Returns: True if rotating, false otherwise.

bool Tucano::Trackball::isTranslating ( void )

inline

Returns wether the trackball is being translated or not.

Returns: True if translating, false otherwise.

void Tucano::Trackball::loadShader ( void )

inline

Load Trackball Shader file.

Eigen::Vector2f Tucano::Trackball::normalizePosition ( const Eigen::Vector2f & pos )

inline

Nomalizes a screen position to range [-1,1].

Parameters

pos	Screen position

Returns: Returns position in normalized coordinates.

virtual void Tucano::Trackball::render	(	Eigen::Affine3f	ext_view_matrix = `Eigen::Affine3f::Identity()`,
		Eigen::Matrix4f	ext_proj_matrix = `Eigen::Matrix4f::Identity()`
	)

inlinevirtual

Renders the trackball representation.

Todo:: setTrackballOrthographicMatrix should be set during viewport resize The external matrices are useful when the trackball should follow a specif object for example, so the main camera matrices should be passed here

Parameters

ext_view_matrix	External view matrix from other global camera
ext_proj_matrix	External projection matrix from other global camera

void Tucano::Trackball::reset ( void )

inline

Resets trackball to initial position and orientation.

virtual Eigen::Quaternion<float> Tucano::Trackball::rotateCamera ( const Eigen::Vector2f & pos )

inlinevirtual

Computes and applies the rotation transformations to the trackball given new position.

Parameters

pos	New mouse position in normalized trackball system

Reimplemented in Tucano::RotationManipulator.

void Tucano::Trackball::rotateViewMatrix ( const Eigen::Affine3f & rot )

inline

Rotates the view matrix by a given rotation matrix. This directly modifies the quaternion of the trackball. Note that the view matrix is always recomputed using the translation, quaternion and zoom.

Parameters

rot	Given rotation matrix.

void Tucano::Trackball::setDefaultRotation ( Eigen::Matrix3f rot )

inline

Sets the default rotation quaternion.

Parameters

rot	Given default rotation as matrix3f

void Tucano::Trackball::setDefaultTranslation ( Eigen::Vector3f t )

inline

Sets the default translation vector.

Parameters

t	Given new default translation vector.

virtual void Tucano::Trackball::setRadius ( float r )

inlinevirtual

Sets the radius.

Reimplemented in Tucano::RotationManipulator.

void Tucano::Trackball::setRenderFlag ( bool flag )

inline

Returns wether the trackball representation should be drawn or not.

Returns: True if trackball representation is being rendered, false otherwise.

Eigen::Matrix4f Tucano::Trackball::setTrackballOrthographicMatrix	(	float	left,
		float	right,
		float	bottom,
		float	top,
		float	near_plane,
		float	far_plane
	)

inline

Sets the trackball projection matrix as orthographic.

Parameters

left	Left plane for orthographic view.
right	Right plane for orthographic view.
bottom	Bottom plane for orthographic view.
top	Top lane for orthographic view.
near_plane	Near plane for orthographic view.
far_plane	Far plane for orthographic view.

Returns: Return the created orthographic matrix.

Eigen::Matrix4f Tucano::Trackball::setTrackballPerspectiveMatrix	(	float	fy,
		float	aspect_ratio,
		float	near_plane,
		float	far_plane
	)

inline

Sets the trackball projection matrix as perspective.

Parameters

fy	Vertical field of view angle.
aspect_ratio	Ratio of width to the height of the viewport.
near_plane	Near plane.
far_plane	Far plane.

Returns: Return the created perspective matrix.

void Tucano::Trackball::setTrackballProjectionMatrix ( const Eigen::Matrix4f & mat )

inline

Sets the projection matrix used for the trackball rendering. Note that this is usually different than the projection matrix for the scene.

Parameters

mat	Given trackball projection matrix.

virtual Eigen::Vector3f Tucano::Trackball::translateCamera ( const Eigen::Vector2f & pos )

inlinevirtual

Computes and applies the translation transformations to the trackball given new position.

Parameters

pos	New mouse position in normalized trackball system

Returns: returns the translation increment

Reimplemented in Tucano::TranslationManipulator.

void Tucano::Trackball::translateViewMatrix ( const Eigen::Vector3f & translation )

inline

Translates the view matrix by a given vector trans. This directly modifies the translation vector of the trackball. Note that the view matrix is always recomputed using the translation, quaternion and zoom.

Parameters

translation Given translation vector.

virtual void Tucano::Trackball::updateViewMatrix ( void )

inlinevirtual

Applies all trackball's transformations to the view matrix.

Reimplemented in Tucano::RotationManipulator, Tucano::TranslationManipulator, and Tucano::DirectionalTrackball.

Member Data Documentation

Eigen::Quaternion<float> Tucano::Trackball::default_quaternion

protected

Trackball's default rotation.

Eigen::Vector3f Tucano::Trackball::default_translation = Eigen::Vector3f (0.0, 0.0, -4.0)

protected

Default translation to move camera away from center.

bool Tucano::Trackball::drawTrackball = true

protected

Flag that indicates wether the trackball's representation should be drawn.

Eigen::Vector3f Tucano::Trackball::finalPosition

protected

Final position vector used to calculate trackball's rotation.

Eigen::Vector2f Tucano::Trackball::finalTranslationPosition

protected

Final position vector used to calculate trackball's translation.

Eigen::Vector3f Tucano::Trackball::initialPosition

protected

Initial position vector used to calculate trackball's rotation.

Eigen::Vector2f Tucano::Trackball::initialTranslationPosition

protected

Initial position vector used to calculate trackball's translation.

Tucano::Mesh Tucano::Trackball::mesh

protected

Trackball visual representation.

Eigen::Quaternion<float> Tucano::Trackball::quaternion

protected

Trackball's quaternion.

float Tucano::Trackball::radius = 0.8

protected

The trackball radius. It's defined as 0.8 times the smallest viewport dimension.

bool Tucano::Trackball::rotating = false

protected

Flag that indicates wether the trackball is being rotated.

Tucano::Shader Tucano::Trackball::trackball_shader

protected

Trackball Shader, used just for rendering the trackball's representation.

Eigen::Matrix4f Tucano::Trackball::trackballProjectionMatrix

protected

Projection matrix used for the trackball's drawing. By default it is defined as an orthogonal projection matrix.

bool Tucano::Trackball::translating = false

protected

Flag that indicates wether the trackball is being translated.

Eigen::Vector3f Tucano::Trackball::translationVector

protected

Trackball's translation vector.

bool Tucano::Trackball::use_default_shaders

protected

Flag to use default shaders set as const strings in class, or pass a directory with custom shaders.

float Tucano::Trackball::zoom = 1.0

protected

The current scale being applied to the View Matrix.

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

tucano/utils/trackball.hpp

Public Member Functions

Protected Attributes

Private Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation