#include <b2Shape.h>

Inherited by b2ChainShape, b2CircleShape, b2EdgeShape, and b2PolygonShape.

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.

Type	GetType () const

virtual int32	GetChildCount () const =0
	Get the number of child primitives.

virtual bool	TestPoint (const b2Transform &xf, const b2Vec2 &p) const =0

virtual void	ComputeDistance (const b2Transform &xf, const b2Vec2 &p, float32 distance, b2Vec2 normal, int32 childIndex) const =0

virtual bool	RayCast (b2RayCastOutput *output, const b2RayCastInput &input, const b2Transform &transform, int32 childIndex) const =0

virtual void	ComputeAABB (b2AABB *aabb, const b2Transform &xf, int32 childIndex) const =0

virtual void	ComputeMass (b2MassData *massData, float32 density) const =0

Public Attributes
Type	m_type

float32	m_radius

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.

Member Function Documentation

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::ComputeDistance	(	const b2Transform &	xf,
		const b2Vec2 &	p,
		float32 *	distance,
		b2Vec2 *	normal,
		int32	childIndex
	)		const

pure virtual

Compute the distance from the current shape to the specified point. This only works for convex shapes.

Parameters

xf	the shape world transform.
p	a point in world coordinates.
distance	returns the distance from the current shape.
normal	returns the direction in which the distance increases.

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.

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.

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.

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

b2Shape.h

Public Types

Public Member Functions

Public Attributes

Detailed Description

Member Function Documentation