CUGL 2.0
Cornell University Game Library
Public Member Functions | Protected Member Functions | Protected Attributes | List of all members
cugl::physics2::ComplexObstacle Class Reference

#include <CUComplexObstacle.h>

Inheritance diagram for cugl::physics2::ComplexObstacle:
cugl::physics2::Obstacle

Public Member Functions

 ComplexObstacle ()
 
virtual ~ComplexObstacle ()
 
virtual b2BodyType getBodyType () const override
 
virtual void setBodyType (b2BodyType value) override
 
virtual Vec2 getPosition () const override
 
virtual void setPosition (const Vec2 value) override
 
virtual void setPosition (float x, float y) override
 
virtual float getX () const override
 
virtual void setX (float value) override
 
virtual float getY () const override
 
virtual void setY (float value) override
 
virtual float getAngle () const override
 
virtual void setAngle (float value) override
 
virtual Vec2 getLinearVelocity () const override
 
virtual void setLinearVelocity (const Vec2 value) override
 
virtual void setLinearVelocity (float x, float y) override
 
virtual float getVX () const override
 
virtual void setVX (float value) override
 
virtual float getVY () const override
 
virtual void setVY (float value) override
 
virtual float getAngularVelocity () const override
 
virtual void setAngularVelocity (float value) override
 
virtual bool isActive () const override
 
virtual void setActive (bool value) override
 
virtual bool isAwake () const override
 
virtual void setAwake (bool value) override
 
virtual bool isSleepingAllowed () const override
 
virtual void setSleepingAllowed (bool value) override
 
virtual bool isBullet () const override
 
virtual void setBullet (bool value) override
 
virtual bool isFixedRotation () const override
 
virtual void setFixedRotation (bool value) override
 
virtual float getGravityScale () const override
 
virtual void setGravityScale (float value) override
 
virtual float getLinearDamping () const override
 
virtual void setLinearDamping (float value) override
 
virtual float getAngularDamping () const override
 
virtual void setAngularDamping (float value) override
 
virtual void setDensity (float value) override
 
virtual void setFriction (float value) override
 
virtual void setRestitution (float value) override
 
virtual void setSensor (bool value) override
 
virtual void setFilterData (b2Filter value) override
 
virtual Vec2 getCentroid () const override
 
virtual void setCentroid (const Vec2 value) override
 
virtual void setCentroid (float x, float y) override
 
virtual float getInertia () const override
 
virtual void setInertia (float value) override
 
virtual float getMass () const override
 
virtual void setMass (float value) override
 
virtual void resetMass () override
 
virtual b2Body * getBody () override
 
const std::vector< std::shared_ptr< Obstacle > > & getBodies ()
 
const std::vector< b2Joint * > & getJoints ()
 
virtual bool activatePhysics (b2World &world) override
 
virtual void deactivatePhysics (b2World &world) override
 
virtual void createFixtures ()
 
virtual void releaseFixtures ()
 
virtual bool createJoints (b2World &world)
 
virtual void update (float delta) override
 
virtual void setDebugColor (Color4 color) override
 
void setDebugColor (Color4 color, bool cascade)
 
virtual void setDebugScene (const std::shared_ptr< scene2::SceneNode > &node) override
 
- Public Member Functions inherited from cugl::physics2::Obstacle
 Obstacle (void)
 
virtual ~Obstacle ()
 
virtual bool init ()
 
virtual bool init (const Vec2 vec)
 
void setBodyState (const b2Body &body)
 
float getDensity () const
 
float getFriction () const
 
float getRestitution () const
 
bool isSensor () const
 
b2Filter getFilterData () const
 
bool isRemoved () const
 
void markRemoved (bool value)
 
bool isDirty () const
 
void markDirty (bool value)
 
const std::function< void(Obstacle *obstacle)> & getListener () const
 
void setListener (const std::function< void(Obstacle *obstacle)> &listener)
 
std::string getName () const
 
void setName (std::string value)
 
std::string toString () const
 
Color4 getDebugColor () const
 
scene2::SceneNodegetDebugScene () const
 
scene2::WireNodegetDebugNode () const
 
bool hasDebug ()
 

Protected Member Functions

virtual void resetDebug () override
 
virtual void updateDebug () override
 

Protected Attributes

b2Body * _body
 
std::vector< std::shared_ptr< Obstacle > > _bodies
 
std::vector< b2Joint * > _joints
 
- Protected Attributes inherited from cugl::physics2::Obstacle
b2BodyDef _bodyinfo
 
b2FixtureDef _fixture
 
b2MassData _massdata
 
bool _masseffect
 
std::shared_ptr< scene2::SceneNode_scene
 
std::shared_ptr< scene2::WireNode_debug
 
Color4 _dcolor
 
std::string _tag
 
std::function< void(Obstacle *obstacle)> _listener
 

Detailed Description

Composite model class to support collisions.

ComplexObstacle instances are built of many bodies, and are assumed to be connected by joints (though this is not actually a requirement). This is the class to use for chains, ropes, levers, and so on. This class does not provide Shape information, and cannot be instantiated directly. There are no default complex objects. You will need to create your own subclasses to use this class.

ComplexObstacle is a hierarchical class. It groups children as Obstacles, not not bodies. So you could have a ComplexObstacle made up of other ComplexObstacles. However, it is not the same as a scene graph. Children have absolute, nott relative, position data. Indeed, this class illustrates the need for decoupling the physics representation from the scene graph.

Transformations to an object of this class are restricted to the root body. They do not automatically effect the children (like a scene graph). If you want changes to the root body to effect the children, you should connect them with joints and allow Box2D to handle this.

Many of the method comments in this class are taken from the Box2d manual by Erin Catto (2011).

Constructor & Destructor Documentation

◆ ComplexObstacle()

cugl::physics2::ComplexObstacle::ComplexObstacle ( )
inline

Creates a new complex physics object at the origin.

NEVER USE A CONSTRUCTOR WITH NEW. If you want to allocate an object on the heap, use one of the static constructors instead (in this case, in one of the subclasses).

◆ ~ComplexObstacle()

virtual cugl::physics2::ComplexObstacle::~ComplexObstacle ( )
virtual

Deletes this physics object and all of its resources.

We have to make the destructor public so that we can polymorphically delete physics objects.

The purpose of this destructor is to warn us if we delete an object pre-maturely.

Member Function Documentation

◆ activatePhysics()

virtual bool cugl::physics2::ComplexObstacle::activatePhysics ( b2World &  world)
overridevirtual

Creates the physics Body(s) for this object, adding them to the world.

This method invokes ActivatePhysics for the individual PhysicsObjects in the list. It also calls the internal method createJoints() to link them all together. You should override that method, not this one, for specific physics objects.

Parameters
worldBox2D world to store body
Returns
true if object allocation succeeded

Reimplemented from cugl::physics2::Obstacle.

◆ createFixtures()

virtual void cugl::physics2::ComplexObstacle::createFixtures ( )
inlinevirtual

Create new fixtures for this body, defining the shape

This method is typically undefined for complex objects. While they need a root body, they rarely need a root shape. However, we provide this method for maximum flexibility.

◆ createJoints()

virtual bool cugl::physics2::ComplexObstacle::createJoints ( b2World &  world)
inlinevirtual

Creates the joints for this object.

This method is executed as part of activePhysics. This is the primary method to override for custom physics objects.

Parameters
worldBox2D world to store joints
Returns
true if object allocation succeeded

◆ deactivatePhysics()

virtual void cugl::physics2::ComplexObstacle::deactivatePhysics ( b2World &  world)
overridevirtual

Destroys the physics Body(s) of this object if applicable, removing them from the world.

Parameters
worldBox2D world that stores body

Reimplemented from cugl::physics2::Obstacle.

◆ getAngle()

virtual float cugl::physics2::ComplexObstacle::getAngle ( ) const
inlineoverridevirtual

Returns the angle of rotation for this body (about the center).

The value is determined by the angle of the root object of this composite structure. The value returned is in radians.

Returns
the angle of rotation for this body

Reimplemented from cugl::physics2::Obstacle.

◆ getAngularDamping()

virtual float cugl::physics2::ComplexObstacle::getAngularDamping ( ) const
inlineoverridevirtual

Returns the angular damping for this body.

Angular damping is use to reduce the angular velocity. Damping is different than friction because friction only occurs with contact. Damping is not a replacement for friction and the two effects should be used together.

Damping parameters should be between 0 and infinity, with 0 meaning no damping, and infinity meaning full damping. Normally you will use a damping value between 0 and 0.1.

This method only grabs the parameter for the root object of this composite structure. For fine-grain control, you will need to loop over all elements in the composite structure.

Returns
the angular damping for this body.

Reimplemented from cugl::physics2::Obstacle.

◆ getAngularVelocity()

virtual float cugl::physics2::ComplexObstacle::getAngularVelocity ( ) const
inlineoverridevirtual

Returns the angular velocity for this physics body

This method uses the velocity for the root object of this composite structure. The rate of change is measured in radians per step

Returns
the angular velocity for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ getBodies()

const std::vector<std::shared_ptr<Obstacle> >& cugl::physics2::ComplexObstacle::getBodies ( )
inline

Returns the collection of component physics objects.

While the vector does not allow you to modify the list, it is possible to modify the individual objects.

Returns
the collection of component physics objects.

◆ getBody()

virtual b2Body* cugl::physics2::ComplexObstacle::getBody ( )
inlineoverridevirtual

Returns the Box2D body for this object.

This method only returrns the root body in this composite structure. For more fine-grain control, you should use the iterator methods.

Returns
the Box2D body for this object.

Reimplemented from cugl::physics2::Obstacle.

◆ getBodyType()

virtual b2BodyType cugl::physics2::ComplexObstacle::getBodyType ( ) const
inlineoverridevirtual

Returns the body type for Box2D physics

If you want to lock a body in place (e.g. a platform) set this value to STATIC. KINEMATIC allows the object to move (and some limited collisions), but ignores external forces (e.g. gravity). DYNAMIC makes this is a full-blown physics object.

This method returns the body type for the root object of this composite structure.

Returns
the body type for Box2D physics

Reimplemented from cugl::physics2::Obstacle.

◆ getCentroid()

virtual Vec2 cugl::physics2::ComplexObstacle::getCentroid ( ) const
inlineoverridevirtual

Returns the center of mass of this body

This method does NOT return a reference to the centroid position. Changes to this vector will not affect the body. However, it returns the same vector each time its is called, and so cannot be used as an allocator.

This method returns the centroid for the root object of this composite structure. While it would make more sense to use the true centroid, that is much more computationally expensive, as that centroid is not rigid.

Returns
the center of mass for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ getGravityScale()

virtual float cugl::physics2::ComplexObstacle::getGravityScale ( ) const
inlineoverridevirtual

Returns the gravity scale to apply to this body

This allows isolated objects to float. Be careful with this, since increased gravity can decrease stability.

This method only grabs the parameter for the root object of this composite structure. For fine-grain control, you will need to loop over all elements in the composite structure.

Returns
the gravity scale to apply to this body

Reimplemented from cugl::physics2::Obstacle.

◆ getInertia()

virtual float cugl::physics2::ComplexObstacle::getInertia ( ) const
inlineoverridevirtual

Returns the rotational inertia of this body

For static bodies, the mass and rotational inertia are set to zero. When a body has fixed rotation, its rotational inertia is zero.

This method only grabs the parameter for the root object of this composite structure. For fine-grain control, you will need to loop over all elements in the composite structure.

Returns
the rotational inertia of this body

Reimplemented from cugl::physics2::Obstacle.

◆ getJoints()

const std::vector<b2Joint*>& cugl::physics2::ComplexObstacle::getJoints ( )
inline

Returns the collection of joints for this object (may be empty).

While the iterable does not allow you to modify the list, it is possible to modify the individual joints.

Returns
the collection of joints for this object.

◆ getLinearDamping()

virtual float cugl::physics2::ComplexObstacle::getLinearDamping ( ) const
inlineoverridevirtual

Returns the linear damping for this body.

Linear damping is use to reduce the linear velocity. Damping is different than friction because friction only occurs with contact. Damping is not a replacement for friction and the two effects should be used together.

Damping parameters should be between 0 and infinity, with 0 meaning no damping, and infinity meaning full damping. Normally you will use a damping value between 0 and 0.1. Most people avoid linear damping because it makes bodies look floaty.

This method only grabs the parameter for the root object of this composite structure. For fine-grain control, you will need to loop over all elements in the composite structure.

Returns
the linear damping for this body.

Reimplemented from cugl::physics2::Obstacle.

◆ getLinearVelocity()

virtual Vec2 cugl::physics2::ComplexObstacle::getLinearVelocity ( ) const
inlineoverridevirtual

Returns the linear velocity for this physics body

This method does NOT return a reference to the velocity vector. Changes to this vector will not affect the body. However, it returns the same vector each time its is called, and so cannot be used as an allocator.

This method returns the velocity for the root of this composite structure.

Returns
the linear velocity for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ getMass()

virtual float cugl::physics2::ComplexObstacle::getMass ( ) const
inlineoverridevirtual

Returns the mass of this body

The value is usually in kilograms. This method only grabs the parameter for the root object of this composite structure. For fine-grain control, you will need to loop over all elements in the composite structure.

Returns
the mass of this body

Reimplemented from cugl::physics2::Obstacle.

◆ getPosition()

virtual Vec2 cugl::physics2::ComplexObstacle::getPosition ( ) const
inlineoverridevirtual

Returns the current position for this physics body

This method does NOT return a reference to the position vector. Changes to this vector will not affect the body. However, it returns the same vector each time its is called, and so cannot be used as an allocator.

This method returns the position for the root object of this composite structure.

Returns
the current position for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ getVX()

virtual float cugl::physics2::ComplexObstacle::getVX ( ) const
inlineoverridevirtual

Returns the x-velocity for this physics body

This method uses the velocity for the root of this composite structure.

Returns
the x-velocity for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ getVY()

virtual float cugl::physics2::ComplexObstacle::getVY ( ) const
inlineoverridevirtual

Returns the y-velocity for this physics body

Returns
the y-velocity for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ getX()

virtual float cugl::physics2::ComplexObstacle::getX ( ) const
inlineoverridevirtual

Returns the x-coordinate for this physics body

This method uses the position for the root object of this composite structure.

Returns
the x-coordinate for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ getY()

virtual float cugl::physics2::ComplexObstacle::getY ( ) const
inlineoverridevirtual

Returns the y-coordinate for this physics body

This method uses the position for the root object of this composite structure.

Returns
the y-coordinate for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ isActive()

virtual bool cugl::physics2::ComplexObstacle::isActive ( ) const
inlineoverridevirtual

Returns true if the body is active

An inactive body not participate in collision or dynamics. This state is similar to sleeping except the body will not be woken by other bodies and the body's fixtures will not be placed in the broad-phase. This means the body will not participate in collisions, ray casts, etc.

This method only tests the activity of the root object of this composite structure. For fine-grain control, you will need to loop over all elements in the composite structure.

Returns
true if the body is active

Reimplemented from cugl::physics2::Obstacle.

◆ isAwake()

virtual bool cugl::physics2::ComplexObstacle::isAwake ( ) const
inlineoverridevirtual

Returns true if the body is awake

An sleeping body is one that has come to rest and the physics engine has decided to stop simulating it to save CPU cycles. If a body is awake and collides with a sleeping body, then the sleeping body wakes up. Bodies will also wake up if a joint or contact attached to them is destroyed. You can also wake a body manually.

This method only tests the status of the root object of this composite structure. For fine-grain control, you will need to loop over all elements in the composite structure.

Returns
true if the body is awake

Reimplemented from cugl::physics2::Obstacle.

◆ isBullet()

virtual bool cugl::physics2::ComplexObstacle::isBullet ( ) const
inlineoverridevirtual

Returns true if this body is a bullet

By default, Box2D uses continuous collision detection (CCD) to prevent dynamic bodies from tunneling through static bodies. Normally CCD is not used between dynamic bodies. This is done to keep performance reasonable. In some game scenarios you need dynamic bodies to use CCD. For example, you may want to shoot a high speed bullet at a stack of dynamic bricks. Without CCD, the bullet might tunnel through the bricks.

Fast moving objects in Box2D can be labeled as bullets. Bullets will perform CCD with both static and dynamic bodies. You should decide what bodies should be bullets based on your game design.

This method only tests the status of the root object of this composite structure. For fine-grain control, you will need to loop over all elements in the composite structure.

Returns
true if this body is a bullet

Reimplemented from cugl::physics2::Obstacle.

◆ isFixedRotation()

virtual bool cugl::physics2::ComplexObstacle::isFixedRotation ( ) const
inlineoverridevirtual

Returns true if this body be prevented from rotating

This is very useful for characters that should remain upright. This method only tests the status of the root object of this composite structure. For fine-grain control, you will need to loop over all elements in the composite structure.

Returns
true if this body be prevented from rotating

Reimplemented from cugl::physics2::Obstacle.

◆ isSleepingAllowed()

virtual bool cugl::physics2::ComplexObstacle::isSleepingAllowed ( ) const
inlineoverridevirtual

Returns false if this body should never fall asleep

An sleeping body is one that has come to rest and the physics engine has decided to stop simulating it to save CPU cycles. If a body is awake and collides with a sleeping body, then the sleeping body wakes up. Bodies will also wake up if a joint or contact attached to them is destroyed. You can also wake a body manually.

This method only tests the status of the root object of this composite structure. For fine-grain control, you will need to loop over all elements in the composite structure.

Returns
false if this body should never fall asleep

Reimplemented from cugl::physics2::Obstacle.

◆ releaseFixtures()

virtual void cugl::physics2::ComplexObstacle::releaseFixtures ( )
inlinevirtual

Release the fixtures for this body, reseting the shape

This method is typically undefined for complex objects. While they need a root body, they rarely need a root shape. However, we provide this method for maximum flexibility.

◆ resetDebug()

virtual void cugl::physics2::ComplexObstacle::resetDebug ( )
overrideprotectedvirtual

Creates the outline of the physics fixtures in the debug wireframe

The debug wireframe is use to outline the fixtures attached to this object. This is very useful when the fixtures have a very different shape than the texture (e.g. a circular shape attached to a square texture).

Reimplemented from cugl::physics2::Obstacle.

◆ resetMass()

virtual void cugl::physics2::ComplexObstacle::resetMass ( )
inlineoverridevirtual

Resets this body to use the mass computed from the its shape and density.

This method only modifies the parameter for the root object of this composite structure. For fine-grain control, you will need to loop over all elements in the composite structure.

Reimplemented from cugl::physics2::Obstacle.

◆ setActive()

virtual void cugl::physics2::ComplexObstacle::setActive ( bool  value)
inlineoverridevirtual

Sets whether the body is active

An inactive body not participate in collision or dynamics. This state is similar to sleeping except the body will not be woken by other bodies and the body's fixtures will not be placed in the broad-phase. This means the body will not participate in collisions, ray casts, etc.

This method affects the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children.

Parameters
valuewhether the body is active

Reimplemented from cugl::physics2::Obstacle.

◆ setAngle()

virtual void cugl::physics2::ComplexObstacle::setAngle ( float  value)
inlineoverridevirtual

Sets the angle of rotation for this body (about the center).

This method sets the angle for the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children. Alternatively attach the other children to the parent with joints so that they move together.

Parameters
valuethe angle of rotation for this body (in radians)

Reimplemented from cugl::physics2::Obstacle.

◆ setAngularDamping()

virtual void cugl::physics2::ComplexObstacle::setAngularDamping ( float  value)
inlineoverridevirtual

Sets the angular damping for this body.

Angular damping is use to reduce the angular velocity. Damping is different than friction because friction only occurs with contact. Damping is not a replacement for friction and the two effects should be used together.

Damping parameters should be between 0 and infinity, with 0 meaning no damping, and infinity meaning full damping. Normally you will use a damping value between 0 and 0.1.

This method affects the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children.

Parameters
valuethe angular damping for this body.

Reimplemented from cugl::physics2::Obstacle.

◆ setAngularVelocity()

virtual void cugl::physics2::ComplexObstacle::setAngularVelocity ( float  value)
inlineoverridevirtual

Sets the angular velocity for this physics body

This method sets the velocity for the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children. Alternatively attach the other children to the parent with joints so that they move together.

Parameters
valuethe angular velocity for this physics body (in radians)

Reimplemented from cugl::physics2::Obstacle.

◆ setAwake()

virtual void cugl::physics2::ComplexObstacle::setAwake ( bool  value)
inlineoverridevirtual

Sets whether the body is awake

An sleeping body is one that has come to rest and the physics engine has decided to stop simulating it to save CPU cycles. If a body is awake and collides with a sleeping body, then the sleeping body wakes up. Bodies will also wake up if a joint or contact attached to them is destroyed. You can also wake a body manually.

This method affects the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children.

Parameters
valuewhether the body is awake

Reimplemented from cugl::physics2::Obstacle.

◆ setBodyType()

virtual void cugl::physics2::ComplexObstacle::setBodyType ( b2BodyType  value)
inlineoverridevirtual

Sets the body type for Box2D physics

If you want to lock a body in place (e.g. a platform) set this value to STATIC. KINEMATIC allows the object to move (and some limited collisions), but ignores external forces (e.g. gravity). DYNAMIC makes this is a full-blown physics object.

This sets the body type for the root body only. If you want to set the type of other objects in this class, iterate over the children.

Parameters
valuethe body type for Box2D physics

Reimplemented from cugl::physics2::Obstacle.

◆ setBullet()

virtual void cugl::physics2::ComplexObstacle::setBullet ( bool  value)
inlineoverridevirtual

Sets whether this body is a bullet

By default, Box2D uses continuous collision detection (CCD) to prevent dynamic bodies from tunneling through static bodies. Normally CCD is not used between dynamic bodies. This is done to keep performance reasonable. In some game scenarios you need dynamic bodies to use CCD. For example, you may want to shoot a high speed bullet at a stack of dynamic bricks. Without CCD, the bullet might tunnel through the bricks.

Fast moving objects in Box2D can be labeled as bullets. Bullets will perform CCD with both static and dynamic bodies. You should decide what bodies should be bullets based on your game design.

This method affects the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children.

Parameters
valuewhether this body is a bullet

Reimplemented from cugl::physics2::Obstacle.

◆ setCentroid() [1/2]

virtual void cugl::physics2::ComplexObstacle::setCentroid ( const Vec2  value)
inlineoverridevirtual

Sets the center of mass for this physics body

This method converts from a Cocos2D vector type to a Box2D vector type. This cuts down on the confusion between vector types.

Parameters
valuethe center of mass for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ setCentroid() [2/2]

virtual void cugl::physics2::ComplexObstacle::setCentroid ( float  x,
float  y 
)
inlineoverridevirtual

Sets the center of mass for this physics body

This method does not keep a reference to the parameter. This method sets the centroid for the root object of this composite structure. While it would make more sense to use the true centroid, that is much more computationally expensive, as that centroid is not rigid.

Parameters
xthe x-coordinate of the center of mass for this physics body
ythe y-coordinate of the center of mass for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ setDebugColor() [1/2]

virtual void cugl::physics2::ComplexObstacle::setDebugColor ( Color4  color)
overridevirtual

Sets the color of the debug wireframe.

The default color is white, which means that the objects will be shown with a white wireframe.

Parameters
colorthe color of the debug wireframe.

Reimplemented from cugl::physics2::Obstacle.

◆ setDebugColor() [2/2]

void cugl::physics2::ComplexObstacle::setDebugColor ( Color4  color,
bool  cascade 
)

Sets the color of the debug wireframe.

The default color is white, which means that the objects will be shown with a white wireframe.

Parameters
colorthe color of the debug wireframe.
cascadewhether to cascade the color to the component objects

◆ setDebugScene()

virtual void cugl::physics2::ComplexObstacle::setDebugScene ( const std::shared_ptr< scene2::SceneNode > &  node)
overridevirtual

Sets the parent scene graph node for the debug wireframe

The given node is the parent coordinate space for drawing physics. All debug nodes for physics objects are drawn within this coordinate space. Setting the visibility of this node to false will disable any debugging. Similarly, setting this value to nullptr will disable any debugging.

This scene graph node is intended for debugging purposes only. If you want a physics body to update a proper texture image, you should either use the method update(float) for subclasses or setListener for decoupled classes.

Parameters
nodehe parent scene graph node for the debug wireframe

Reimplemented from cugl::physics2::Obstacle.

◆ setDensity()

virtual void cugl::physics2::ComplexObstacle::setDensity ( float  value)
overridevirtual

Sets the density of this body

The density is typically measured in usually in kg/m^2. The density can be zero or positive. You should generally use similar densities for all your fixtures. This will improve stacking stability.

This method affects the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children.

Parameters
valuethe density of this body

Reimplemented from cugl::physics2::Obstacle.

◆ setFilterData()

virtual void cugl::physics2::ComplexObstacle::setFilterData ( b2Filter  value)
overridevirtual

Sets the filter data for this object

Collision filtering allows you to prevent collision between fixtures. For example, say you make a character that rides a bicycle. You want the bicycle to collide with the terrain and the character to collide with the terrain, but you don't want the character to collide with the bicycle (because they must overlap). Box2D supports such collision filtering using categories and groups.

A value of null removes all collision filters. This method affects ALL of the bodies in this composite structure. For fine-grain control, you will need to loop over all elements in the composite structure.

Parameters
valuethe filter data for this object

Reimplemented from cugl::physics2::Obstacle.

◆ setFixedRotation()

virtual void cugl::physics2::ComplexObstacle::setFixedRotation ( bool  value)
inlineoverridevirtual

Sets whether this body be prevented from rotating

This is very useful for characters that should remain upright.

This method affects the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children.

Parameters
valuewhether this body be prevented from rotating

Reimplemented from cugl::physics2::Obstacle.

◆ setFriction()

virtual void cugl::physics2::ComplexObstacle::setFriction ( float  value)
overridevirtual

Sets the friction coefficient of this body

The friction parameter is usually set between 0 and 1, but can be any non-negative value. A friction value of 0 turns off friction and a value of 1 makes the friction strong. When the friction force is computed between two shapes, Box2D must combine the friction parameters of the two parent fixtures. This is done with the geometric mean.

This method affects the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children.

Parameters
valuethe friction coefficient of this body

Reimplemented from cugl::physics2::Obstacle.

◆ setGravityScale()

virtual void cugl::physics2::ComplexObstacle::setGravityScale ( float  value)
inlineoverridevirtual

Sets the gravity scale to apply to this body

This allows isolated objects to float. Be careful with this, since increased gravity can decrease stability.

This method affects the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children.

Parameters
valuethe gravity scale to apply to this body

Reimplemented from cugl::physics2::Obstacle.

◆ setInertia()

virtual void cugl::physics2::ComplexObstacle::setInertia ( float  value)
inlineoverridevirtual

Sets the rotational inertia of this body

For static bodies, the mass and rotational inertia are set to zero. When a body has fixed rotation, its rotational inertia is zero.

This method only modifies the parameter for the root object of this composite structure. For fine-grain control, you will need to loop over all elements in the composite structure.

Parameters
valuethe rotational inertia of this body

Reimplemented from cugl::physics2::Obstacle.

◆ setLinearDamping()

virtual void cugl::physics2::ComplexObstacle::setLinearDamping ( float  value)
inlineoverridevirtual

Sets the linear damping for this body.

Linear damping is use to reduce the linear velocity. Damping is different than friction because friction only occurs with contact. Damping is not a replacement for friction and the two effects should be used together.

Damping parameters should be between 0 and infinity, with 0 meaning no damping, and infinity meaning full damping. Normally you will use a damping value between 0 and 0.1. Most people avoid linear damping because it makes bodies look floaty.

This method affects the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children.

Parameters
valuethe linear damping for this body.

Reimplemented from cugl::physics2::Obstacle.

◆ setLinearVelocity() [1/2]

virtual void cugl::physics2::ComplexObstacle::setLinearVelocity ( const Vec2  value)
inlineoverridevirtual

Sets the linear velocity for this physics body

This method converts from a Cocos2D vector type to a Box2D vector type. This cuts down on the confusion between vector types.

Parameters
valuethe linear velocity for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ setLinearVelocity() [2/2]

virtual void cugl::physics2::ComplexObstacle::setLinearVelocity ( float  x,
float  y 
)
inlineoverridevirtual

Sets the linear velocity for this physics body

This method sets the linear velocity for the root of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children. Alternatively attach the other children to the parent with joints so that they move together.

Parameters
xthe x-coordinate of the linear velocity
ythe y-coordinate of the linear velocity

Reimplemented from cugl::physics2::Obstacle.

◆ setMass()

virtual void cugl::physics2::ComplexObstacle::setMass ( float  value)
inlineoverridevirtual

Sets the mass of this body

The value is usually in kilograms. This method only modifies the parameter for the root object of this composite structure. For fine-grain control, you will need to loop over all elements in the composite structure.

Parameters
valuethe mass of this body

Reimplemented from cugl::physics2::Obstacle.

◆ setPosition() [1/2]

virtual void cugl::physics2::ComplexObstacle::setPosition ( const Vec2  value)
inlineoverridevirtual

Sets the current position for this physics body

This method converts from a Cocos2D vector type to a Box2D vector type. This cuts down on the confusion between vector types.

Parameters
valuethe current position for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ setPosition() [2/2]

virtual void cugl::physics2::ComplexObstacle::setPosition ( float  x,
float  y 
)
inlineoverridevirtual

Sets the current position for this physics body

This method sets the position for the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children. Alternatively attach the other children to the parent with joints so that they move together.

Parameters
xthe x-coordinate of the linear velocity
ythe y-coordinate of the linear velocity

Reimplemented from cugl::physics2::Obstacle.

◆ setRestitution()

virtual void cugl::physics2::ComplexObstacle::setRestitution ( float  value)
overridevirtual

Sets the restitution of this body

Restitution is used to make objects bounce. The restitution value is usually set to be between 0 and 1. Consider dropping a ball on a table. A value of zero means the ball won't bounce. This is called an inelastic collision. A value of one means the ball's velocity will be exactly reflected. This is called a perfectly elastic collision.

This method affects the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children.

Parameters
valuethe restitution of this body

Reimplemented from cugl::physics2::Obstacle.

◆ setSensor()

virtual void cugl::physics2::ComplexObstacle::setSensor ( bool  value)
overridevirtual

Sets whether this object is a sensor.

Sometimes game logic needs to know when two entities overlap yet there should be no collision response. This is done by using sensors. A sensor is an entity that detects collision but does not produce a response.

This method affects the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children.

Parameters
valuewhether this object is a sensor.

Reimplemented from cugl::physics2::Obstacle.

◆ setSleepingAllowed()

virtual void cugl::physics2::ComplexObstacle::setSleepingAllowed ( bool  value)
inlineoverridevirtual

Sets whether the body should ever fall asleep

An sleeping body is one that has come to rest and the physics engine has decided to stop simulating it to save CPU cycles. If a body is awake and collides with a sleeping body, then the sleeping body wakes up. Bodies will also wake up if a joint or contact attached to them is destroyed. You can also wake a body manually.

This method affects the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children.

Parameters
valuewhether the body should ever fall asleep

Reimplemented from cugl::physics2::Obstacle.

◆ setVX()

virtual void cugl::physics2::ComplexObstacle::setVX ( float  value)
inlineoverridevirtual

Sets the x-velocity for this physics body

This method sets the velocity for the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children. Alternatively attach the other children to the parent with joints so that they move together.

Parameters
valuethe x-velocity for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ setVY()

virtual void cugl::physics2::ComplexObstacle::setVY ( float  value)
inlineoverridevirtual

Sets the y-velocity for this physics body

This method sets the velocity for the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children. Alternatively attach the other children to the parent with joints so that they move together.

Parameters
valuethe y-velocity for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ setX()

virtual void cugl::physics2::ComplexObstacle::setX ( float  value)
inlineoverridevirtual

Sets the x-coordinate for this physics body

This method sets the position for the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children. Alternatively attach the other children to the parent with joints so that they move together.

Parameters
valuethe x-coordinate for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ setY()

virtual void cugl::physics2::ComplexObstacle::setY ( float  value)
inlineoverridevirtual

Sets the y-coordinate for this physics body

This method sets the position for the root body of this composite structure only. If you want to set the value for any of the child obstacles, iterate over the children. Alternatively attach the other children to the parent with joints so that they move together.

Parameters
valuethe y-coordinate for this physics body

Reimplemented from cugl::physics2::Obstacle.

◆ update()

virtual void cugl::physics2::ComplexObstacle::update ( float  delta)
overridevirtual

Updates the object's physics state (NOT GAME LOGIC).

This method is called AFTER the collision resolution state. Therefore, it should not be used to process actions or any other gameplay information. Its primary purpose is to adjust changes to the fixture, which have to take place after collision.

Parameters
deltaTiming values from parent loop

Reimplemented from cugl::physics2::Obstacle.

◆ updateDebug()

virtual void cugl::physics2::ComplexObstacle::updateDebug ( )
overrideprotectedvirtual

Repositions the debug wireframe so that it agrees with the physics object.

The debug wireframe is use to outline the fixtures attached to this object. This is very useful when the fixtures have a very different shape than the texture (e.g. a circular shape attached to a square texture).

Reimplemented from cugl::physics2::Obstacle.

Member Data Documentation

◆ _bodies

std::vector<std::shared_ptr<Obstacle> > cugl::physics2::ComplexObstacle::_bodies
protected

A complex physics object has multiple bodies

◆ _body

b2Body* cugl::physics2::ComplexObstacle::_body
protected

A root body for this box 2d.

◆ _joints

std::vector<b2Joint*> cugl::physics2::ComplexObstacle::_joints
protected

Potential joints for connecting the multiple bodies


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