Class to store colour information. More...

#include <Colour.h>

Public Member Functions
	Colour ()
	Colour default constructor. More...

	Colour (double r, double g, double b)
	Colour constructor. More...

	Colour (const Colour &colour)
	Colour copy constructor. More...

	~Colour ()
	Colour destructor. More...

Colour &	operator= (const Colour &colour)
	Colour assignment operator. More...

Colour	operator- () const
	Colour unary negation. More...

Colour &	operator+= (const Colour &colour)
	Colour addition-assignment operator. More...

Colour &	operator-= (const Colour &colour)
	Colour subtraction-assignment operator. More...

Colour &	operator*= (const Colour &colour)
	Colour multiplication-assignment operator. More...

Colour &	operator*= (double s)
	Colour-scalar multiplication-assignment operator. More...

Colour &	operator/= (double s)
	Colour-scalar division-assignment operator. More...

void	clip ()
	Enforce bounds on Colour components. More...

Public Attributes
double	red
	The red component of the Colour. More...

double	green
	The green component of the Colour. More...

double	blue
	The blue component of the Colour. More...

Related Functions
(Note that these are not member functions.)
Colour	operator+ (const Colour &lhs, const Colour &rhs)
	Colour addition. More...

Colour	operator- (const Colour &lhs, const Colour &rhs)
	Colour subtraction. More...

Colour	operator* (const Colour &lhs, const Colour &rhs)
	Colour multiplication. More...

Colour	operator* (double s, const Colour &colour)
	Scalar-Colour multiplication. More...

Colour	operator* (const Colour &colour, double s)
	Colour-scalar multiplication. More...

Colour	operator/ (const Colour &colour, double s)
	Colour-scalar division. More...

Detailed Description

Class to store colour information.

Colours are an important aspect of Material objects, and the basic quanitity that a ray tracer comptues for a ray. Colours are represented as RGB triples, with values in the range [0,1]. Note that during computation, Colour values may go outside of the range [0,1]. Because of this, these bounds are not enforced. However Colours can be brought back into this range with the clip() method.

Colour objects also have basic arithmetic operators defined on them. These are applied independently to each component. This is an important distinction from Vector and Matrix objects, which have particular rules for arithmetic (particularly multiplication).

Constructor & Destructor Documentation

◆ Colour() [1/3]

Colour::Colour ( )

Colour default constructor.

Creates a new colour with all values set to 0 (black).

◆ Colour() [2/3]

Colour::Colour	(	double	r,
		double	g,
		double	b
	)

Colour constructor.

Creates a new colour with the given red, green, and blue values.

Parameters

r	The red value of the new Colour.
g	The green value of the new Colour.
b	The blue value of the new Colour.

◆ Colour() [3/3]

Colour::Colour ( const Colour & colour )

Colour copy constructor.

Parameters

colour The Colour to copy.

◆ ~Colour()

Colour::~Colour ( )

Colour destructor.

Member Function Documentation

◆ clip()

void Colour::clip ( )

Enforce bounds on Colour components.

Colour component values should lie in the range [0,1], but during computation it is sometimes valid for values to lie outside this range. This method clips values to this range by simple truncation.

◆ operator*=() [1/2]

Colour & Colour::operator*= ( const Colour & colour )

Colour multiplication-assignment operator.

Multiply one Colour by another in place.

Parameters

colour The Colour to multiply this by.

Returns: A reference to the updated this, to allow chaining of assignment.

◆ operator*=() [2/2]

Colour & Colour::operator*= ( double s )

Colour-scalar multiplication-assignment operator.

Multiply a Colour by a scalar in place.

Parameters

s	The scalar to multiply `this` by.

Returns: A reference to the updated this, to allow chaining of assignment.

◆ operator+=()

Colour & Colour::operator+= ( const Colour & colour )

Colour addition-assignment operator.

Add one Colour to another in place.

Parameters

colour The Colour to add to this.

Returns: A reference to the updated this, to allow chaining of assignment.

◆ operator-()

Colour Colour::operator- ( ) const

Colour unary negation.

Given a Colour (R, G, B), the negated Colour is (-R, -G, -B).

Returns: The negated Colour.

◆ operator-=()

Colour & Colour::operator-= ( const Colour & colour )

Colour subtraction-assignment operator.

Subtract one Colour from another in place.

Parameters

colour The Colour to subtract from this.

Returns: A reference to the updated this, to allow chaining of assignment.

◆ operator/=()

Colour & Colour::operator/= ( double s )

Colour-scalar division-assignment operator.

Divide a Colour by a scalar in place.

Parameters

s	The scalar to divide `this` by.

Returns: A reference to the updated this, to allow chaining of assignment.

◆ operator=()

Colour & Colour::operator= ( const Colour & colour )

Colour assignment operator.

Parameters

colour The Colour to assign to this.

Returns: A reference to this to allow for chaining of assignment.

Friends And Related Function Documentation

◆ operator*() [1/3]

Colour operator*	(	const Colour &	colour,
		double	s
	)

The product of a Colour, (R, G, B) and a scalar, s, is (s*R, s*G, s*B).

Parameters

colour	The Colour on the left hand side of the * operator.
s	The scalar on the right hand side of the * operator.

Returns: The product of lhs and rhs.

◆ operator*() [2/3]

Colour operator*	(	const Colour &	lhs,
		const Colour &	rhs
	)

Given two Colours, (R1, G1, B1) and (R2, G2, B2), their product is (R1*R2, G1*G2, B1*B2). Note that this is different from the usual Vector dot and cross products.

Parameters

lhs	The Colour on the left hand side of the * operator.
rhs	The Colour on the right hand side of the * operator.

Returns: The product of lhs and rhs.

◆ operator*() [3/3]

Colour operator*	(	double	s,
		const Colour &	colour
	)

The product of a Colour, (R, G, B) and a scalar, s, is (s*R, s*G, s*B).

Parameters

s	The scalar on the left hand side of the * operator.
colour	The Colour on the right hand side of the * operator.

Returns: The product of lhs and rhs.

◆ operator+()

Colour operator+	(	const Colour &	lhs,
		const Colour &	rhs
	)

Given two Colours, (R1, G1, B1) and (R2, G2, B2), their sum is (R1+R2, G1+G2, B1+B2).

Parameters

lhs	The Colour on the left hand side of the + operator.
rhs	The Colour on the right hand side of the + operator.

Returns: The sum of lhs and rhs.

◆ operator-()

Colour operator-	(	const Colour &	lhs,
		const Colour &	rhs
	)

Given two Colours, (R1, G1, B1) and (R2, G2, B2), their difference is (R1-R2, G1-G2, B1-B2).

Parameters

lhs	The Colour on the left hand side of the - operator.
rhs	The Colour on the right hand side of the - operator.

Returns: The difference between lhs and rhs.

◆ operator/()

Colour operator/	(	const Colour &	colour,
		double	s
	)

The division of a Colour, (R, G, B) by a scalar, s, is (R/s, G/s, B/s).

Parameters

colour	The Colour on the left hand side of the / operator.
s	The scalar on the right hand side of the / operator.

Returns: The division of lhs by rhs.

Member Data Documentation

◆ blue

double Colour::blue

The blue component of the Colour.

◆ green

double Colour::green

The green component of the Colour.

◆ red

double Colour::red

The red component of the Colour.

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

Public Member Functions

Public Attributes

Related Functions

Detailed Description

Constructor & Destructor Documentation

◆ Colour() [1/3]

◆ Colour() [2/3]

◆ Colour() [3/3]

◆ ~Colour()

Member Function Documentation

◆ clip()

◆ operator*=() [1/2]

◆ operator*=() [2/2]

◆ operator+=()

◆ operator-()

◆ operator-=()

◆ operator/=()

◆ operator=()

Friends And Related Function Documentation

◆ operator*() [1/3]

◆ operator*() [2/3]

◆ operator*() [3/3]

◆ operator+()

◆ operator-()

◆ operator/()

Member Data Documentation

◆ blue

◆ green

◆ red