Inheritance diagram for vtTrackball:

Public Member Functions
void	SetRadius (float fRadius)

float	GetRadius () const

void	SetRotateButton (int button, int modifier=0, bool bExact=true)

void	SetZoomButton (int button, int modifier=0, bool bExact=true)

void	SetTranslateButton (int button, int modifier=0, bool bExact=true)

void	SetZoomScale (float s)

void	SetRotScale (float s)

void	SetTransScale (float s)

void	SetDirection (float fTheta, float fPhi)

void	MoveDirection (float fTheta, float fPhi)

void	OnMouse (vtMouseEvent &event)
	Virtual handler, to catch mouse events, can be overridden by your engine class.

void	Eval ()

Public Member Functions inherited from vtLastMouse
void	GetNormalizedMouseCoords (float &mx, float &my)

Public Member Functions inherited from vtEngine
osg::Referenced *	GetTarget (uint which=0)

void	AddTarget (osg::Referenced *ptr)

void	RemoveTarget (osg::Referenced *ptr)

uint	NumTargets ()
	Return the number of targets for this engine.

virtual void	OnKey (int key, int flags)
	Virtual handler, to catch keyboard events, can be overridden by your engine class.

virtual void	OnWindowSize (int width, int height)
	Virtual handler, to catch resize events, can be overridden by your engine class.

Additional Inherited Members
Public Attributes inherited from vtLastMouse
int	m_buttons

IPoint2	m_pos

int	m_flags

Detailed Description

A Trackball is a navigation engine which can move a Camera (or any other Transform target) and move it around a center point based on mouse input.

You can set which combinations of mouse buttons and modifier keys will rotate, zoom and translate the target. The default is:

Member Function Documentation

void vtTrackball::Eval ( )

virtual

Virtual handler, will be called every frame to do the work of the engine. You must override this if you want your engine to be useful.

Reimplemented from vtEngine.

float vtTrackball::GetRadius ( ) const

Get the radius, the distance from the pivot point that the Trackball rotates around.

void vtTrackball::MoveDirection	(	float	fTheta,
		float	fPhi
	)

Shift the direction the trackball is facing, by a given offset.

Parameters

fTheta,fPhi Polar coordinates for the target relative to the pivot point.

void vtTrackball::SetDirection	(	float	fTheta,
		float	fPhi
	)

Set the direction the trackball is facing.

Parameters

fTheta,fPhi Polar coordinates for the target relative to the pivot point.

void vtTrackball::SetRadius ( float fRadius )

Set the radius, the distance from the pivot point that the Trackball rotates around.

void vtTrackball::SetRotateButton	(	int	button,
		int	modifier = `0`,
		bool	bExact = `true`
	)

Set the buttons and modifier keys that will cause the Trackball to rotate.

Parameters

button	The button state (VT_LEFT, VT_RIGHT, and/or VT_MIDDLE)
modifier	The modifier state (VT_SHIFT, VT_CONTROL, and/or VT_ALT)
bExact	If true, then exactly this button must occur. Otherwise, any button state that includes this state will suffice.

void vtTrackball::SetRotScale ( float s )

Set the scale factor for rotation, which controls how fast the Trackball will spin its target.

void vtTrackball::SetTranslateButton	(	int	button,
		int	modifier = `0`,
		bool	bExact = `true`
	)

Set the buttons and modifier keys that will cause the Trackball to translate.

Parameters

button	The button state (VT_LEFT, VT_RIGHT, and/or VT_MIDDLE)
modifier	The modifier state (VT_SHIFT, VT_CONTROL, and/or VT_ALT)
bExact	If true, then exactly this button must occur. Otherwise, any button state that includes this state will suffice.

void vtTrackball::SetTransScale ( float s )

Set the scale factor for translation, which controls how fast the Trackball will translate its target.

void vtTrackball::SetZoomButton	(	int	button,
		int	modifier = `0`,
		bool	bExact = `true`
	)

Set the buttons and modifier keys that will cause the Trackball to zoom.

Parameters

button	The button state (VT_LEFT, VT_RIGHT, and/or VT_MIDDLE)
modifier	The modifier state (VT_SHIFT, VT_CONTROL, and/or VT_ALT)
bExact	If true, then exactly this button must occur. Otherwise, any button state that includes this state will suffice.

void vtTrackball::SetZoomScale ( float s )

Set the scale factor for zoom, which controls how fast the Trackball will zoom in/out.