A camera is generally used to display aa area of a game scene, usually tracking some actor. More...

#include <CzCamera.h>

Inheritance diagram for CzCamera:

Public Member Functions
CzMatrix3 &	getTransform ()
void	setPosition (float x, float y)
CzVec2	getPosition () const
void	setVelocity (float x, float y)
CzVec2	getVelocity () const
void	setVelocityDamping (float x, float y)
CzVec2	getVelocityDamping () const
void	setFollowSpeed (float x, float y)
CzVec2	getFollowSpeed () const
void	setScale (float scale)
float	getScale () const
void	setAngle (float angle)
float	getAngle () const
void	setTargetX (const char *target_name)
	Sets target x-axis actor for camera to follow on its x-axis.
void	setTargetX (CzActor *target)
	Sets target x-axis actor for camera to follow on its x-axis.
void	setTargetY (const char *target_name)
	Sets target y-axis actor for camera to follow on its y-axis.
void	setTargetY (CzActor *target)
	Sets target y-axis actor for camera to follow on its y-axis.
void	setTransformDirty (bool dirty)
bool	isTransformDirty () const
void	setTouchPanX (bool pan)
bool	isTouchPanX () const
void	setTouchPanY (bool pan)
bool	isTouchPanY () const
void	setIgnoreActors (bool ignore)
bool	getIgnoreActors () const
virtual bool	setProperty (unsigned int property_name, const CzXomlProperty &data, bool delta)
	Sets the named property of the Camera.
bool	setProperty (const char *property_name, const CzString &data, bool delta)
	Sets the named property of the actor.
virtual bool	setProperty (unsigned int property_name, const CzString &data, bool delta)
	Sets the named property of the actor.
bool	getProperty (const char *property_name, CzXomlProperty &prop)
	Gets the named property of the actor.
virtual bool	getProperty (unsigned int property_name, CzXomlProperty &prop)
	CzCamera ()
virtual	~CzCamera ()
virtual void	Update (float dt)
	Updates the given dt.
int	LoadFromXoml (IzXomlResource parebt, bool load_children, CzXmlNode node)
	Creates an instance of this class from XOML.
Static Public Member Functions
static void	InitClass ()
	Initialises the class.
static void	ReleaseClass ()
static bool	_setName (IzXomlResource *target, const CzXomlProperty &prop, bool add)
static CzXomlProperty	_getName (IzXomlResource *target)
static bool	_setTag (IzXomlResource *target, const CzXomlProperty &prop, bool add)
static bool	_setPosition (IzXomlResource *target, const CzXomlProperty &prop, bool add)
static CzXomlProperty	_getPosition (IzXomlResource *target)
static bool	_setScale (IzXomlResource *target, const CzXomlProperty &prop, bool add)
static CzXomlProperty	_getScale (IzXomlResource *target)
static bool	_setAngle (IzXomlResource *target, const CzXomlProperty &prop, bool add)
static CzXomlProperty	_getAngle (IzXomlResource *target)
static bool	_setVelocity (IzXomlResource *target, const CzXomlProperty &prop, bool add)
static CzXomlProperty	_getVelocity (IzXomlResource *target)
static bool	_setVelocityDamping (IzXomlResource *target, const CzXomlProperty &prop, bool add)
static CzXomlProperty	_getVelocityDamping (IzXomlResource *target)
static bool	_setTouchPanX (IzXomlResource *target, const CzXomlProperty &prop, bool add)
static CzXomlProperty	_getTouchPanX (IzXomlResource *target)
static bool	_setTouchPanY (IzXomlResource *target, const CzXomlProperty &prop, bool add)
static CzXomlProperty	_getTouchPanY (IzXomlResource *target)
static bool	_setIgnoreActors (IzXomlResource *target, const CzXomlProperty &prop, bool add)
static CzXomlProperty	_getIgnoreActors (IzXomlResource *target)
static bool	_setTargetX (IzXomlResource *target, const CzXomlProperty &prop, bool add)
static bool	_setTargetY (IzXomlResource *target, const CzXomlProperty &prop, bool add)
static bool	_setFollowSpeed (IzXomlResource *target, const CzXomlProperty &prop, bool add)
static CzXomlProperty	_getFollowSpeed (IzXomlResource *target)
Protected Attributes
CzScene *	Scene
	Parent scene.
CzMatrix3	Transform
	The combined camera transform.
CzVec2	Position
	Position of camera within scene.
CzVec2	Velocity
	Velocity of camera.
CzVec2	VelocityDamping
	Velocity cadmping applied to slow the camera.
CzVec2	FollowSpeed
	Speed at which to follow target (1.0 is max)
float	Scale
	Cameras scale.
float	Angle
	Cameras angle.
bool	TransformDirty
	Marks camera transform needs rebuilding.
CzActor *	TargetX
	Object that the camera is targeting on the x axis.
CzActor *	TargetY
	Object that the camera is targeting on the y axis.
unsigned int	TargetXHash
	Hash of object that the camera is targeting on the x axis.
unsigned int	TargetYHash
	Hash of object that the camera is targeting on the y axis.
bool	TouchPanX
	If true then the camera will pan along the x-axis with the users touch.
bool	TouchPanY
	If true then the camera will pan along the y-axis with the users touch.
bool	IgnoreActors
	if an actor is currently focused then it will usually prevent touch panning, this will disable that
Static Protected Attributes
static CzXomlClassDef *	CameraClassDef = NULL

Detailed Description

A camera is generally used to display aa area of a game scene, usually tracking some actor.

A camera is a view into the scene from a specific position, angle and scale. In order to move, rotate and scale a scene a camera should be created and attached to it. To create a camera you use the Camera XOML tag:

XOML Example:

<!-- Create a camera -->
<Camera Name="Camera1" />

To attach the camera to the scene we add the Camera attribute to the scene definition:

<Scene Name="Scene1" Current="true" Camera="Camera1">

When we move, scale or rotate a scene we are actually modifying the camera view within the scene. When we move the camera objects tend to move in the opposite direction, for example moving the camera left moves the scene actors to the right. If you think about how a real camera works, when you move the camera in one direction the view seen by the camera moves in the opposite direction.

Its possible to create a number of different cameras and switch between them to offer different views into the scene.

Cameras offer a great out of the box feature called touch panning, which enables the user to pan the camera around a scene on the x and y axis by dragging their finger around the scene. Take a look at the ScenePanning example for an example showing how to use touch panning.

Lets take a look at what properties the Camera tag supports:

Name (string) - Cameras resource name
- Position (x, y) - Start position of the camera
- Angle (degrees) - Rotation of the camera
- Scale (scale factor) - Scale of the camera (can be used for zoom effects)
- TouchPanX / TouchPanY (boolean) - Setting true causes the camera to move around when the user drags their finger on the screen using velocity obtained from the speed of the users drag. Separate X and Y axis panning can be enabled / disabled.
- VelocityDamping (x, y) - Amount of damping to apply to the cameras velocity (x, y) each frame. This value when set to a value of less than 1.0, 1.0 will cause the camera to slow down over time.
- IgnoreActors (boolean) - When set to true and touch panel is enabled, dragging a finger over an actor will still be classed as a touch pan drag. This option basically allows the user to touch pan the scene regardless of what the user touches on the screen.
- TargetX (actor name, write-only) � An actor that the camera will be used to track its x-axis position
- TargetY (actor name, write-only) � An actor that the camera will be used to track its y-axis position
- FollowSpeed (x, y) � The speed at which the camera should track the specified actor(s). Higher values will catch the camera up to the actors target position faster
- Tag (string) - Group tag

Some of these properties can be modified via the scene such as Position, Angle and Scale as changes to these properties go straight to the attached camera. You can set all properties for a camera via LUA using the camera.set() function.

Constructor & Destructor Documentation

CzCamera::CzCamera ( ) [inline]

virtual CzCamera::~CzCamera ( ) [inline, virtual]

Member Function Documentation

CzXomlProperty CzCamera::_getAngle ( IzXomlResource * target ) [static]

CzXomlProperty CzCamera::_getFollowSpeed ( IzXomlResource * target ) [static]

CzXomlProperty CzCamera::_getIgnoreActors ( IzXomlResource * target ) [static]

CzXomlProperty CzCamera::_getName ( IzXomlResource * target ) [static]

CzXomlProperty CzCamera::_getPosition ( IzXomlResource * target ) [static]

CzXomlProperty CzCamera::_getScale ( IzXomlResource * target ) [static]

CzXomlProperty CzCamera::_getTouchPanX ( IzXomlResource * target ) [static]

CzXomlProperty CzCamera::_getTouchPanY ( IzXomlResource * target ) [static]

CzXomlProperty CzCamera::_getVelocity ( IzXomlResource * target ) [static]

CzXomlProperty CzCamera::_getVelocityDamping ( IzXomlResource * target ) [static]

bool CzCamera::_setAngle	(	IzXomlResource *	target,
		const CzXomlProperty &	prop,
		bool	add
	)		`[static]`

bool CzCamera::_setFollowSpeed	(	IzXomlResource *	target,
		const CzXomlProperty &	prop,
		bool	add
	)		`[static]`

bool CzCamera::_setIgnoreActors	(	IzXomlResource *	target,
		const CzXomlProperty &	prop,
		bool	add
	)		`[static]`

bool CzCamera::_setName	(	IzXomlResource *	target,
		const CzXomlProperty &	prop,
		bool	add
	)		`[static]`

bool CzCamera::_setPosition	(	IzXomlResource *	target,
		const CzXomlProperty &	prop,
		bool	add
	)		`[static]`

bool CzCamera::_setScale	(	IzXomlResource *	target,
		const CzXomlProperty &	prop,
		bool	add
	)		`[static]`

bool CzCamera::_setTag	(	IzXomlResource *	target,
		const CzXomlProperty &	prop,
		bool	add
	)		`[static]`

bool CzCamera::_setTargetX	(	IzXomlResource *	target,
		const CzXomlProperty &	prop,
		bool	add
	)		`[static]`

bool CzCamera::_setTargetY	(	IzXomlResource *	target,
		const CzXomlProperty &	prop,
		bool	add
	)		`[static]`

bool CzCamera::_setTouchPanX	(	IzXomlResource *	target,
		const CzXomlProperty &	prop,
		bool	add
	)		`[static]`

bool CzCamera::_setTouchPanY	(	IzXomlResource *	target,
		const CzXomlProperty &	prop,
		bool	add
	)		`[static]`

bool CzCamera::_setVelocity	(	IzXomlResource *	target,
		const CzXomlProperty &	prop,
		bool	add
	)		`[static]`

bool CzCamera::_setVelocityDamping	(	IzXomlResource *	target,
		const CzXomlProperty &	prop,
		bool	add
	)		`[static]`

float CzCamera::getAngle ( ) const [inline]

CzVec2 CzCamera::getFollowSpeed ( ) const [inline]

bool CzCamera::getIgnoreActors ( ) const [inline]

CzVec2 CzCamera::getPosition ( ) const [inline]

bool CzCamera::getProperty	(	const char *	property_name,
		CzXomlProperty &	prop
	)

Gets the named property of the actor.

Returns the named property of the actor. The properties value is returned in a CzXomlProperty which is a structure that contains a union of all possible property types.

Parameters:

	property_name	Name of the property.
[out]	prop	The property data.

Returns:: true if it succeeds, false if property does not exist.

bool CzCamera::getProperty	(	unsigned int	property_name,
		CzXomlProperty &	prop
	)		`[virtual]`

Returns the named property of the actor. The properties value is returned in a CzXomlProperty which is a structure that contains a union of all possible property types.

Parameters:

	property_name	Name of the property as a string hash (faster searching).
[in,out]	prop	The property.

Returns:: true if it succeeds, false if property does not exist.

float CzCamera::getScale ( ) const [inline]

CzMatrix3& CzCamera::getTransform ( ) [inline]

CzVec2 CzCamera::getVelocity ( ) const [inline]

CzVec2 CzCamera::getVelocityDamping ( ) const [inline]

void CzCamera::InitClass ( ) [static]

Initialises the class.

Sets up the classes avaiiable properties. Used by the XOML system to find, set amd get class properties.

bool CzCamera::isTouchPanX ( ) const [inline]

bool CzCamera::isTouchPanY ( ) const [inline]

bool CzCamera::isTransformDirty ( ) const [inline]

int CzCamera::LoadFromXoml	(	IzXomlResource *	parent,
		bool	load_children,
		CzXmlNode *	node
	)		`[virtual]`

Creates an instance of this class from XOML.

LoadFromXoml is the main method used by all classes that can be instantiated from XOML mark-up. This method creates an instance of this class from the supplied XML node structure specified by node. if parent is not NULL then the created instance will utilise the supplied parent to determine where it should live within the app. For example, if the parent is a scene then the camera will be placed in that scene. If load_chlldren is true then any child nodes contained within the node will also be loaded.

Parameters:

[in]	parent	If non-null, the parent.
	load_children	true to load child nodes.
[in]	node	If non-null, the XOML markup node that defines this object

Returns:: nergative value for error. if 0 then processing of further XOML will stop.

Implements IzXomlResource.

void CzCamera::ReleaseClass ( ) [static]

void CzCamera::setAngle ( float angle ) [inline]

void CzCamera::setFollowSpeed	(	float	x,
		float	y
	)		`[inline]`

void CzCamera::setIgnoreActors ( bool ignore ) [inline]

void CzCamera::setPosition	(	float	x,
		float	y
	)		`[inline]`

bool CzCamera::setProperty	(	unsigned int	property_name,
		const CzXomlProperty &	data,
		bool	delta
	)		`[virtual]`

Sets the named property of the Camera.

Sets the named property of this Camera. The properties value supplied will be converted. If delta is set to true then the existing value of the property will be added to instead of replaced.

Parameters:

	property_name	Name of the property as a string hash (faster searching).
[in]	data	The property data.
	delta	true if property should be added to instead of replaced.

Returns:: true if it succeeds, false if property does not exist.

bool CzCamera::setProperty	(	const char *	property_name,
		const CzString &	data,
		bool	delta
	)

Sets the named property of the actor.

Sets the named property of this actor. The properties value (data) is supplied as a string and will be converted. If delta is set to true then the existing value of the property will be added to instead of replaced.

Parameters:

	property_name	Name of the property.
[in]	data	The property data.
	delta	true if property should be added to instead of replaced.

Returns:: true if it succeeds, false if property does not exist.

bool CzCamera::setProperty	(	unsigned int	property_name,
		const CzString &	data,
		bool	delta
	)		`[virtual]`

Sets the named property of the actor.

Sets the named property of this actor. The properties value (data) is supplied as a string and will be converted. If delta is set to true then the existing value of the property will be added to instead of replaced.

Parameters:

	property_name	Name of the property as a string hash (faster searching).
[in]	data	The property data.
	delta	true if property should be added to instead of replaced.