orxonox::mbool Struct Reference

mbool is a small helper class that acts like a bool, but keeps track of the number of its state changes. More...

#include </home/jenkins/workspace/orxonox_doxygen_trunk/src/libraries/util/mbool.h>

Public Member Functions
constexpr	mbool (bool value=false)
	Constructor: Creates the mbool and initializes the boolean value (default to false). More...
constexpr	mbool (const mbool &value)
	Copy-constructor, copies state and memory. More...
	~mbool ()=default
	Destructor does nothing but not defining it might create a symbol (class is header only) More...
unsigned char &	getMemory ()
	Returns the memory value. More...
constexpr	operator bool () const
	Implicitly converts the mbool to a bool. More...
constexpr bool	operator! () const
	Returns the inverted state of the bool (doesn't change the internal state). More...
constexpr bool	operator!= (bool other) const
	Compares the mbool to a bool, returns true if the bool has a different value than the state of the mbool. More...
constexpr bool	operator!= (const mbool &other) const
	Compares two mbools, returns true if they have a different memory value. More...
mbool &	operator++ ()
	Increases the memory which also inverts it's state (++mbool). More...
mbool	operator++ (int)
	Increases the memory which also inverts it's state (mbool++). More...
mbool &	operator= (bool value)
	Assigns a boolean value (and increases the memory value if the value is different to the old value). More...
mbool &	operator= (const mbool &value)
	Assigns another mbool, copies state and memory. More...
constexpr bool	operator== (bool other) const
	Compares the mbool to a bool, returns true if the bool has the same value as the state of the mbool. More...
constexpr bool	operator== (const mbool &other) const
	Compares two mbools, returns true if their memory matches. More...

Private Attributes
union {
bool   bool_: 1
	The boolean state of the mbool, is located on the first bit of the memory variable. More...
unsigned char   memory_
	The memory of the mbool, counts the state-changes (and the first bit represents also the boolean value) More...
}	value_
	A union containing the state and the memory of the mbool. More...

Detailed Description

mbool is a small helper class that acts like a bool, but keeps track of the number of its state changes.

The mbool class acts like a bool, but it has an internal counter that counts the number state changes (i.e. when the bool changes from true to false or back). This is used in the network if a boolean value is synchronized, because if a value changes quickly from false to true and back in the same tick, the clients will never be notified of this action. By using mbool however this behaviour is fixed, which is important for triggers and other objects.

Note

This is efficiently solved by using a union that combines a counter and a boolean bitfield of size 1. The boolean value corresponds always to the first bit of the counter - this means, if the counter is incremented, the boolean state changes. On the other hand, if you want to change the state, you can simply increase the counter.

Constructor & Destructor Documentation

constexpr orxonox::mbool::mbool ( bool  value = false )

inline

Constructor: Creates the mbool and initializes the boolean value (default to false).

constexpr orxonox::mbool::mbool ( const mbool &  value )

inline

Copy-constructor, copies state and memory.

orxonox::mbool::~mbool ( )

inlinedefault

Destructor does nothing but not defining it might create a symbol (class is header only)

Member Function Documentation

unsigned char& orxonox::mbool::getMemory ( )

inline

Returns the memory value.

constexpr orxonox::mbool::operator bool ( ) const

inline

Implicitly converts the mbool to a bool.

constexpr bool orxonox::mbool::operator! ( ) const

inline

Returns the inverted state of the bool (doesn't change the internal state).

constexpr bool orxonox::mbool::operator!= ( bool  other ) const

inline

Compares the mbool to a bool, returns true if the bool has a different value than the state of the mbool.

constexpr bool orxonox::mbool::operator!= ( const mbool &  other ) const

inline

Compares two mbools, returns true if they have a different memory value.

mbool& orxonox::mbool::operator++ ( )

inline

Increases the memory which also inverts it's state (++mbool).

mbool orxonox::mbool::operator++ ( int  )

inline

Increases the memory which also inverts it's state (mbool++).

mbool& orxonox::mbool::operator= ( bool  value )

inline

Assigns a boolean value (and increases the memory value if the value is different to the old value).

mbool& orxonox::mbool::operator= ( const mbool &  value )

inline

Assigns another mbool, copies state and memory.

constexpr bool orxonox::mbool::operator== ( bool  other ) const

inline

Compares the mbool to a bool, returns true if the bool has the same value as the state of the mbool.

constexpr bool orxonox::mbool::operator== ( const mbool &  other ) const

inline

Compares two mbools, returns true if their memory matches.

Member Data Documentation

bool orxonox::mbool::bool_

The boolean state of the mbool, is located on the first bit of the memory variable.

unsigned char orxonox::mbool::memory_

The memory of the mbool, counts the state-changes (and the first bit represents also the boolean value)

union { ... } orxonox::mbool::value_

A union containing the state and the memory of the mbool.

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

• libraries/util/mbool.h