b2Shape Class Reference

#include <b2Shape.h>

Inheritance diagram for b2Shape:

Public Types
enum	Type {   e_circle = 0, e_edge = 1, e_polygon = 2, e_chain = 3,   e_typeCount = 4 }

Public Member Functions
virtual b2Shape *	Clone (b2BlockAllocator *allocator) const =0
	Clone the concrete shape using the provided allocator. More...
virtual void	ComputeAABB (b2AABB *aabb, const b2Transform &xf, int32 childIndex) const =0
virtual void	ComputeMass (b2MassData *massData, float32 density) const =0
virtual int32	GetChildCount () const =0
	Get the number of child primitives. More...
Type	GetType () const
virtual bool	RayCast (b2RayCastOutput *output, const b2RayCastInput &input, const b2Transform &transform, int32 childIndex) const =0
virtual bool	TestPoint (const b2Transform &xf, const b2Vec2 &p) const =0
virtual	~b2Shape ()

Public Attributes
float32	m_radius
Type	m_type

Detailed Description

A shape is used for collision detection. You can create a shape however you like. Shapes used for simulation in b2World are created automatically when a b2Fixture is created. Shapes may encapsulate a one or more child shapes.

Definition at line 42 of file b2Shape.h.

Member Enumeration Documentation

enum b2Shape::Type

Enumerator
e_circle
e_edge
e_polygon
e_chain
e_typeCount

Definition at line 46 of file b2Shape.h.

Constructor & Destructor Documentation

virtual b2Shape::~b2Shape ( )

inlinevirtual

Definition at line 55 of file b2Shape.h.

Member Function Documentation

virtual b2Shape* b2Shape::Clone ( b2BlockAllocator *  allocator ) const

pure virtual

Clone the concrete shape using the provided allocator.

Implemented in b2ChainShape, b2EdgeShape, b2PolygonShape, and b2CircleShape.

virtual void b2Shape::ComputeAABB ( b2AABB *  aabb, const b2Transform &  xf, int32  childIndex  ) const

pure virtual

Given a transform, compute the associated axis aligned bounding box for a child shape.

Parameters

aabb	returns the axis aligned box.
xf	the world transform of the shape.
childIndex	the child shape

Implemented in b2ChainShape, b2PolygonShape, b2EdgeShape, and b2CircleShape.

virtual void b2Shape::ComputeMass ( b2MassData *  massData, float32  density  ) const

pure virtual

Compute the mass properties of this shape using its dimensions and density. The inertia tensor is computed about the local origin.

Parameters

massData	returns the mass data for this shape.
density	the density in kilograms per meter squared.

Implemented in b2ChainShape, b2PolygonShape, b2EdgeShape, and b2CircleShape.

virtual int32 b2Shape::GetChildCount ( ) const

pure virtual

Get the number of child primitives.

Implemented in b2ChainShape, b2EdgeShape, b2PolygonShape, and b2CircleShape.

b2Shape::Type b2Shape::GetType ( ) const

inline

Get the type of this shape. You can use this to down cast to the concrete shape.

Returns

the shape type.

Definition at line 96 of file b2Shape.h.

virtual bool b2Shape::RayCast ( b2RayCastOutput *  output, const b2RayCastInput &  input, const b2Transform &  transform, int32  childIndex  ) const

pure virtual

Cast a ray against a child shape.

Parameters

output	the ray-cast results.
input	the ray-cast input parameters.
transform	the transform to be applied to the shape.
childIndex	the child shape index

Implemented in b2ChainShape, b2PolygonShape, b2EdgeShape, and b2CircleShape.

virtual bool b2Shape::TestPoint ( const b2Transform &  xf, const b2Vec2 &  p  ) const

pure virtual

Test a point for containment in this shape. This only works for convex shapes.

Parameters

xf	the shape world transform.
p	a point in world coordinates.

Implemented in b2ChainShape, b2PolygonShape, b2EdgeShape, and b2CircleShape.

Member Data Documentation

float32 b2Shape::m_radius

Definition at line 93 of file b2Shape.h.

Type b2Shape::m_type

Definition at line 92 of file b2Shape.h.

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

• b2Shape.h