2-D unit vector. More...

#include <playrho/d2/UnitVec.hpp>

Public Types
using	checker_type = detail::UnitMagnitudeChecker< underlying_type >
	Alias for checker type this class template was instantiated for.

using	const_iterator = underlying_type::const_iterator
	Constant iterator type.

using	const_pointer = underlying_type::const_pointer
	Constant pointer type.

using	const_reference = underlying_type::const_reference
	Constant reference type.

using	const_reverse_iterator = underlying_type::const_reverse_iterator
	Constant reverse iterator type.

using	exception_type = InvalidArgument
	Alias for the exception type possibly thrown by this class.

template<typename T >
using	PolarCoord = std::enable_if_t< IsArithmeticV< T >, std::pair< UnitVec, T > >
	Polar coordinate. More...

using	size_type = underlying_type::size_type
	Size type.

using	underlying_type = Vector< value_type, N >
	Alias for the underlying type of this object.

using	value_type = Real
	Value type used for the coordinate values of this vector.

Public Member Functions
constexpr	UnitVec () noexcept=default
	Default constructor. More...

	UnitVec (const underlying_type &v)
	Initializing constructor. More...

constexpr UnitVec	Absolute () const noexcept
	Gets the absolute value.

constexpr const_reference	at (size_type pos) const
	Gets a constant reference to the requested element. More...

const_iterator	begin () const noexcept
	Gets a "begin" iterator.

const_iterator	cbegin () const noexcept
	Gets a "begin" iterator.

const_iterator	cend () const noexcept
	Gets an "end" iterator.

const_reverse_iterator	crbegin () const noexcept
	Gets a reverse "begin" iterator.

const_reverse_iterator	crend () const noexcept
	Gets a reverse "end" iterator.

constexpr const_pointer	data () const noexcept
	Direct access to data.

const_iterator	end () const noexcept
	Gets an "end" iterator.

constexpr UnitVec	FlipX () const noexcept
	Flips the X value.

constexpr UnitVec	FlipXY () const noexcept
	Flips the X and Y values.

constexpr UnitVec	FlipY () const noexcept
	Flips the Y value.

constexpr UnitVec	GetFwdPerpendicular () const noexcept
	Gets a vector clockwise (forward-clockwise) perpendicular to this vector. More...

constexpr UnitVec	GetRevPerpendicular () const noexcept
	Gets a vector counter-clockwise (reverse-clockwise) perpendicular to this vector. More...

constexpr auto	GetX () const noexcept
	Gets the "X" value.

constexpr auto	GetY () const noexcept
	Gets the "Y" value.

constexpr	operator underlying_type () const noexcept
	Implicitly gets the underlying value via a cast or implicit conversion.

constexpr UnitVec	operator+ () const noexcept
	Positive operator.

constexpr UnitVec	operator- () const noexcept
	Negation operator.

constexpr const_reference	operator[] (size_type pos) const noexcept
	Gets a constant reference to the requested element. More...

const_reverse_iterator	rbegin () const noexcept
	Gets a reverse "begin" iterator.

const_reverse_iterator	rend () const noexcept
	Gets a reverse "end" iterator.

constexpr UnitVec	Rotate (const UnitVec &amount) const noexcept
	Rotates the unit vector by the given amount. More...

Static Public Member Functions
static constexpr bool	empty () noexcept
	Whether empty. More...

static UnitVec	Get (Angle angle) noexcept
	Gets the given angled unit vector. More...

template<typename T >
static PolarCoord< T >	Get (const T x, const T y, const UnitVec &fallback=GetDefaultFallback()) noexcept
	Gets the unit vector & magnitude from the given parameters. More...

static constexpr UnitVec	GetDefaultFallback () noexcept
	Gets the default fallback.

static constexpr UnitVec	GetDown () noexcept
	Gets the down-ward oriented unit vector. More...

static constexpr UnitVec	GetDownRight () noexcept
	Gets the -45 degree unit vector. More...

static constexpr UnitVec	GetLeft () noexcept
	Gets the left-ward oriented unit vector. More...

static constexpr UnitVec	GetRight () noexcept
	Gets the right-ward oriented unit vector. More...

static constexpr UnitVec	GetUp () noexcept
	Gets the up-ward oriented unit vector. More...

static constexpr UnitVec	GetUpRight () noexcept
	Gets the 45 degree unit vector. More...

static constexpr UnitVec	GetZero () noexcept
	Gets the non-oriented unit vector.

static constexpr size_type	max_size () noexcept
	Gets the max size.

static constexpr size_type	size () noexcept
	Gets the size.

static auto	ThrowIfInvalid (const underlying_type &value) -> void
	Throws this class's exception type if the given value is invalid. More...

static auto	Validate (const underlying_type &value) -> underlying_type

Static Public Attributes
static constexpr auto	N = std::size_t{2}
	Dimensionality of this type.

Detailed Description

2-D unit vector.

This is a 2-dimensional directional vector.

Invariant: The magnitude of a non-oriented unit vector is zero. The magnitude of an oriented unit vector is approximately one, and is always more than zero.

Member Typedef Documentation

◆ PolarCoord

template<typename T >

using playrho::d2::UnitVec::PolarCoord = std::enable_if_t<IsArithmeticV<T>, std::pair<UnitVec, T> >

Polar coordinate.

This is a direction and magnitude pair defined by the unit vector class.

Note: A magnitude of 0 indicates that no conclusive direction could be determined. The magnitude will otherwise be a normal value.

Constructor & Destructor Documentation

◆ UnitVec() [1/2]

constexpr playrho::d2::UnitVec::UnitVec ( )

constexprdefaultnoexcept

Default constructor.

Constructs a non-oriented unit vector.

Postcondition: GetX() and GetY() return zero.

◆ UnitVec() [2/2]

playrho::d2::UnitVec::UnitVec ( const underlying_type & v )

inlineexplicit

Initializing constructor.

Explicitly converts a vector of unit magnitude to an object or throws.

Note: This function is intended for use with values having a magnitude believed to already be within two ULPs of the real value of 1. Use a function like the polar coordinate returning Get function instead for arbitrary values.

Postcondition: GetX and GetY return the X and Y components respectively of the given value, exactly.

Exceptions

exception_type Constructed with the returned error - if the checker returned a non-null explanatory string.

Member Function Documentation

◆ at()

constexpr const_reference playrho::d2::UnitVec::at ( size_type pos ) const

inlineconstexpr

Gets a constant reference to the requested element.

Exceptions

InvalidArgument if given a position that's >= size().

◆ empty()

static constexpr bool playrho::d2::UnitVec::empty ( )

inlinestaticconstexprnoexcept

Whether empty.

Note: Always false for N > 0.

◆ Get() [1/2]

UnitVec playrho::d2::UnitVec::Get ( Angle angle )

staticnoexcept

Gets the given angled unit vector.

Note: For angles that are meant to be at exact multiples of the quarter turn, better accuracy will be had by using one of the four oriented unit vector returning methods - for the right, up, left, down orientations.

◆ Get() [2/2]

template<typename T >

static PolarCoord<T> playrho::d2::UnitVec::Get	(	const T	x,
		const T	y,
		const UnitVec &	fallback = `GetDefaultFallback()`
	)

inlinestaticnoexcept

Gets the unit vector & magnitude from the given parameters.

See also: HypotGet.

◆ GetDown()

static constexpr UnitVec playrho::d2::UnitVec::GetDown ( )

inlinestaticconstexprnoexcept

Gets the down-ward oriented unit vector.

Note: This is the actual value for the 3/4 turned (270 degree angled) unit vector.; This is the reverse perpendicular unit vector of the left oriented vector.; This is the forward perpendicular unit vector of the right oriented vector.

Examples: Compositor.cpp, and PulleyJoint.cpp.

Referenced by Get(), and playrho::d2::RayCast().

◆ GetDownRight()

static constexpr UnitVec playrho::d2::UnitVec::GetDownRight ( )

inlinestaticconstexprnoexcept

Gets the -45 degree unit vector.

This is the unit vector in the positive X and negative Y quadrant where |X| == |Y|.

◆ GetFwdPerpendicular()

constexpr UnitVec playrho::d2::UnitVec::GetFwdPerpendicular ( ) const

inlineconstexprnoexcept

Gets a vector clockwise (forward-clockwise) perpendicular to this vector.

This returns the unit vector (y, -x).

Returns: A clockwise 90-degree rotation of this vector.

See also: GetRevPerpendicular.

Referenced by playrho::d2::GetFwdPerpendicular().

◆ GetLeft()

static constexpr UnitVec playrho::d2::UnitVec::GetLeft ( )

inlinestaticconstexprnoexcept

Gets the left-ward oriented unit vector.

Note: This is the actual value for the 2/4 turned (180 degree angled) unit vector.; This is the reverse perpendicular unit vector of the up oriented vector.; This is the forward perpendicular unit vector of the down oriented vector.

Examples: Compositor.cpp, and WorldBody.cpp.

Referenced by Get(), and playrho::d2::RayCast().

◆ GetRevPerpendicular()

constexpr UnitVec playrho::d2::UnitVec::GetRevPerpendicular ( ) const

inlineconstexprnoexcept

Gets a vector counter-clockwise (reverse-clockwise) perpendicular to this vector.

This returns the unit vector (-y, x).

Returns: A counter-clockwise 90-degree rotation of this vector.

See also: GetFwdPerpendicular.

Referenced by playrho::d2::GetRevPerpendicular(), and playrho::d2::GetYAxis().

◆ GetRight()

static constexpr UnitVec playrho::d2::UnitVec::GetRight ( )

inlinestaticconstexprnoexcept

Gets the right-ward oriented unit vector.

Note: This is the value for the 0/4 turned (0 angled) unit vector.; This is the reverse perpendicular unit vector of the down oriented vector.; This is the forward perpendicular unit vector of the up oriented vector.

Examples: Compositor.cpp, PrismaticJoint.cpp, Shape.cpp, WheelJoint.cpp, World.cpp, WorldBody.cpp, and WorldContact.cpp.

Referenced by Get(), playrho::d2::RayCast(), playrho::d2::part::Compositor< P1, P2, P3, P4, P5, P6 >::Rotate(), and playrho::d2::detail::Rotate().

◆ GetUp()

static constexpr UnitVec playrho::d2::UnitVec::GetUp ( )

inlinestaticconstexprnoexcept

Gets the up-ward oriented unit vector.

Note: This is the actual value for the 1/4 turned (90 degree angled) unit vector.; This is the reverse perpendicular unit vector of the right oriented vector.; This is the forward perpendicular unit vector of the left oriented vector.

Examples: Compositor.cpp, GearJoint.cpp, Shape.cpp, and WorldShape.cpp.

Referenced by Get(), and playrho::d2::RayCast().

◆ GetUpRight()

static constexpr UnitVec playrho::d2::UnitVec::GetUpRight ( )

inlinestaticconstexprnoexcept

Gets the 45 degree unit vector.

This is the unit vector in the positive X and Y quadrant where X == Y.

Examples: WorldBody.cpp.

◆ operator[]()

constexpr const_reference playrho::d2::UnitVec::operator[] ( size_type pos ) const

inlineconstexprnoexcept

Gets a constant reference to the requested element.

Note: No bounds checking is performed.

Parameters

pos	Valid element index to get value for.

Precondition: The given position parameter (pos), is less than size().

◆ Rotate()

constexpr UnitVec playrho::d2::UnitVec::Rotate ( const UnitVec & amount ) const

inlineconstexprnoexcept

Rotates the unit vector by the given amount.

Parameters

amount Expresses the angular difference from the right-ward oriented unit vector to rotate this unit vector by.

Returns: Result of rotating this unit vector by the given amount.

◆ ThrowIfInvalid()

static auto playrho::d2::UnitVec::ThrowIfInvalid ( const underlying_type & value ) -> void

inlinestatic

Throws this class's exception type if the given value is invalid.

Exceptions

exception_type Constructed with the returned error - if the checker returned a non-null explanatory string.

See also: exception_type.

Referenced by Validate().

◆ Validate()

static auto playrho::d2::UnitVec::Validate ( const underlying_type & value ) -> underlying_type

inlinestatic

Validates the given value using the checker_type type and returns the value given if it checks out.

Exceptions

exception_type Constructed with the returned error - if the checker returned a non-null explanatory string.

Returns: Value given.

Referenced by UnitVec().

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

Library/include/playrho/d2/UnitVec.hpp
Library/source/playrho/d2/UnitVec.cpp

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Detailed Description

Member Typedef Documentation

◆ PolarCoord

Constructor & Destructor Documentation

◆ UnitVec() [1/2]

◆ UnitVec() [2/2]

Member Function Documentation

◆ at()

◆ empty()

◆ Get() [1/2]

◆ Get() [2/2]

◆ GetDown()

◆ GetDownRight()

◆ GetFwdPerpendicular()

◆ GetLeft()

◆ GetRevPerpendicular()

◆ GetRight()

◆ GetUp()

◆ GetUpRight()

◆ operator[]()

◆ Rotate()

◆ ThrowIfInvalid()

◆ Validate()