juce_MathsFunctions.h File Reference

Classes
struct	TypeHelpers::ParameterType< Type >
	The ParameterType struct is used to find the best type to use when passing some kind of object as a parameter. More...
struct	TypeHelpers::SmallestFloatType< Type >
	These templates are designed to take a type, and if it's a double, they return a double type; for anything else, they return a float type. More...
struct	TypeHelpers::SmallestFloatType< double >

Namespaces
	TypeHelpers
	This namespace contains a few template classes for helping work out class type variations.

Macros
#define	JUCE_UNDENORMALISE(x)   { (x) += 0.1f; (x) -= 0.1f; }
	This macro can be applied to a float variable to check whether it contains a denormalised value, and to normalise it if necessary. More...
#define	PARAMETER_TYPE(a)   typename TypeHelpers::ParameterType<a>::type
	A helpful macro to simplify the use of the ParameterType template. More...

Typedefs
typedef signed char	int8
	A platform-independent 8-bit signed integer type. More...
typedef unsigned char	uint8
	A platform-independent 8-bit unsigned integer type. More...
typedef signed short	int16
	A platform-independent 16-bit signed integer type. More...
typedef unsigned short	uint16
	A platform-independent 16-bit unsigned integer type. More...
typedef signed int	int32
	A platform-independent 32-bit signed integer type. More...
typedef unsigned int	uint32
	A platform-independent 32-bit unsigned integer type. More...
typedef long long	int64
	A platform-independent 64-bit integer type. More...
typedef unsigned long long	uint64
	A platform-independent 64-bit unsigned integer type. More...
typedef int	pointer_sized_int
	A signed integer type that's guaranteed to be large enough to hold a pointer without truncating it. More...
typedef unsigned int	pointer_sized_uint
	An unsigned integer type that's guaranteed to be large enough to hold a pointer without truncating it. More...

Functions
template<typename Type >
Type	jmax (const Type a, const Type b)
	Returns the larger of two values. More...
template<typename Type >
Type	jmax (const Type a, const Type b, const Type c)
	Returns the larger of three values. More...
template<typename Type >
Type	jmax (const Type a, const Type b, const Type c, const Type d)
	Returns the larger of four values. More...
template<typename Type >
Type	jmin (const Type a, const Type b)
	Returns the smaller of two values. More...
template<typename Type >
Type	jmin (const Type a, const Type b, const Type c)
	Returns the smaller of three values. More...
template<typename Type >
Type	jmin (const Type a, const Type b, const Type c, const Type d)
	Returns the smaller of four values. More...
template<typename Type >
Type	jmap (Type value0To1, Type targetRangeMin, Type targetRangeMax)
	Remaps a normalised value (between 0 and 1) to a target range. More...
template<typename Type >
Type	jmap (Type sourceValue, Type sourceRangeMin, Type sourceRangeMax, Type targetRangeMin, Type targetRangeMax)
	Remaps a value from a source range to a target range. More...
template<typename Type >
Type	findMinimum (const Type *data, int numValues)
	Scans an array of values, returning the minimum value that it contains. More...
template<typename Type >
Type	findMaximum (const Type *values, int numValues)
	Scans an array of values, returning the maximum value that it contains. More...
template<typename Type >
void	findMinAndMax (const Type *values, int numValues, Type &lowest, Type &highest)
	Scans an array of values, returning the minimum and maximum values that it contains. More...
template<typename Type >
Type	jlimit (const Type lowerLimit, const Type upperLimit, const Type valueToConstrain) noexcept
	Constrains a value to keep it within a given range. More...
template<typename Type >
bool	isPositiveAndBelow (Type valueToTest, Type upperLimit) noexcept
	Returns true if a value is at least zero, and also below a specified upper limit. More...
template<>
bool	isPositiveAndBelow (const int valueToTest, const int upperLimit) noexcept
template<typename Type >
bool	isPositiveAndNotGreaterThan (Type valueToTest, Type upperLimit) noexcept
	Returns true if a value is at least zero, and also less than or equal to a specified upper limit. More...
template<>
bool	isPositiveAndNotGreaterThan (const int valueToTest, const int upperLimit) noexcept
template<typename Type >
void	swapVariables (Type &variable1, Type &variable2)
	Handy function to swap two values. More...
template<typename Type1 >
void	ignoreUnused (const Type1 &) noexcept
	Handy function for avoiding unused variables warning. More...
template<typename Type1 , typename Type2 >
void	ignoreUnused (const Type1 &, const Type2 &) noexcept
template<typename Type1 , typename Type2 , typename Type3 >
void	ignoreUnused (const Type1 &, const Type2 &, const Type3 &) noexcept
template<typename Type1 , typename Type2 , typename Type3 , typename Type4 >
void	ignoreUnused (const Type1 &, const Type2 &, const Type3 &, const Type4 &) noexcept
template<typename Type , int N>
int	numElementsInArray (Type(&array)[N])
	Handy function for getting the number of elements in a simple const C array. More...
template<typename Type >
Type	juce_hypot (Type a, Type b) noexcept
	Using juce_hypot is easier than dealing with the different types of hypot function that are provided by the various platforms and compilers. More...
int64	abs64 (const int64 n) noexcept
	64-bit abs function. More...
float	degreesToRadians (float degrees) noexcept
	Converts an angle in degrees to radians. More...
double	degreesToRadians (double degrees) noexcept
	Converts an angle in degrees to radians. More...
float	radiansToDegrees (float radians) noexcept
	Converts an angle in radians to degrees. More...
double	radiansToDegrees (double radians) noexcept
	Converts an angle in radians to degrees. More...
template<typename NumericType >
bool	juce_isfinite (NumericType) noexcept
	The isfinite() method seems to vary between platforms, so this is a platform-independent function for it. More...
template<>
bool	juce_isfinite (float value) noexcept
template<>
bool	juce_isfinite (double value) noexcept
template<typename FloatType >
int	roundToInt (const FloatType value) noexcept
	Fast floating-point-to-integer conversion. More...
int	roundToInt (int value) noexcept
int	roundToIntAccurate (const double value) noexcept
	Fast floating-point-to-integer conversion. More...
int	roundDoubleToInt (const double value) noexcept
	Fast floating-point-to-integer conversion. More...
int	roundFloatToInt (const float value) noexcept
	Fast floating-point-to-integer conversion. More...
template<typename IntegerType >
bool	isPowerOfTwo (IntegerType value)
	Returns true if the specified integer is a power-of-two. More...
int	nextPowerOfTwo (int n) noexcept
	Returns the smallest power-of-two which is equal to or greater than the given integer. More...
int	countNumberOfBits (uint32 n) noexcept
	Returns the number of bits in a 32-bit integer. More...
int	countNumberOfBits (uint64 n) noexcept
	Returns the number of bits in a 64-bit integer. More...
template<typename IntegerType >
IntegerType	negativeAwareModulo (IntegerType dividend, const IntegerType divisor) noexcept
	Performs a modulo operation, but can cope with the dividend being negative. More...
template<typename NumericType >
NumericType	square (NumericType n) noexcept
	Returns the square of its argument. More...

Variables
const double	double_Pi = 3.1415926535897932384626433832795
	A predefined value for Pi, at double-precision. More...
const float	float_Pi = 3.14159265358979323846f
	A predefined value for Pi, at single-precision. More...

Macro Definition Documentation

#define JUCE_UNDENORMALISE

(

x

)

{ (x) += 0.1f; (x) -= 0.1f; }

This macro can be applied to a float variable to check whether it contains a denormalised value, and to normalise it if necessary.

On CPUs that aren't vulnerable to denormalisation problems, this will have no effect.

Referenced by Reverb::processMono().

#define PARAMETER_TYPE

(

a

)

typename TypeHelpers::ParameterType<a>::type

A helpful macro to simplify the use of the ParameterType template.

See also

ParameterType

Typedef Documentation

typedef signed char int8

A platform-independent 8-bit signed integer type.

typedef unsigned char uint8

A platform-independent 8-bit unsigned integer type.

typedef signed short int16

A platform-independent 16-bit signed integer type.

typedef unsigned short uint16

A platform-independent 16-bit unsigned integer type.

typedef signed int int32

A platform-independent 32-bit signed integer type.

typedef unsigned int uint32

A platform-independent 32-bit unsigned integer type.

typedef long long int64

A platform-independent 64-bit integer type.

typedef unsigned long long uint64

A platform-independent 64-bit unsigned integer type.

typedef int pointer_sized_int

A signed integer type that's guaranteed to be large enough to hold a pointer without truncating it.

typedef unsigned int pointer_sized_uint

An unsigned integer type that's guaranteed to be large enough to hold a pointer without truncating it.

Function Documentation

template<typename Type >

Type jmax	(	const Type	a,
		const Type	b
	)

Returns the larger of two values.

Referenced by Rectangle< int >::enlargeIfAdjacent(), Rectangle< int >::expand(), Rectangle< int >::expanded(), Rectangle< int >::findAreaContainingPoints(), PluginBusUtilities::findMaxNumberOfChannelsForBus(), Decibels::gainToDecibels(), RectangleList< int >::getBounds(), Rectangle< int >::getIntersection(), Range< int64 >::getIntersectionWith(), AudioBuffer< float >::getMagnitude(), Rectangle< int >::getUnion(), Range< int64 >::getUnionWith(), Rectangle< int >::intersectRectangle(), Rectangle< int >::intersectRectangles(), jmax(), AudioUnitHelpers::CoreAudioBufferList::prepare(), ResizableBorderComponent::Zone::resizeRectangleBy(), Rectangle< int >::setLeft(), Range< int64 >::setLength(), Draggable3DOrientation::setRadius(), Rectangle< int >::setTop(), Rectangle< int >::transformedBy(), Rectangle< int >::withBottom(), Rectangle< int >::withLeft(), Rectangle< int >::withRight(), Range< int64 >::withStart(), and Rectangle< int >::withTop().

template<typename Type >

Type jmax	(	const Type	a,
		const Type	b,
		const Type	c
	)

Returns the larger of three values.

template<typename Type >

Type jmax	(	const Type	a,
		const Type	b,
		const Type	c,
		const Type	d
	)

Returns the larger of four values.

References jmax().

template<typename Type >

Type jmin	(	const Type	a,
		const Type	b
	)

Returns the smaller of two values.

Referenced by Rectangle< int >::constrainedWithin(), SelectedItemSet< SelectableItemType >::deselectAll(), Rectangle< int >::enlargeIfAdjacent(), Rectangle< int >::findAreaContainingPoints(), PluginBusUtilities::findMaxNumberOfChannelsForBus(), RectangleList< int >::getBounds(), Rectangle< int >::getIntersection(), Range< int64 >::getIntersectionWith(), Draggable3DOrientation::getQuaternion(), Rectangle< int >::getUnion(), Range< int64 >::getUnionWith(), Rectangle< int >::intersectRectangle(), Rectangle< int >::intersectRectangles(), jmin(), Rectangle< int >::removeFromBottom(), Rectangle< int >::removeFromLeft(), Rectangle< int >::removeFromRight(), Rectangle< int >::removeFromTop(), SparseSet< int >::removeRange(), ResizableBorderComponent::Zone::resizeRectangleBy(), SelectedItemSet< SelectableItemType >::selectOnly(), Rectangle< int >::setBottom(), Rectangle< int >::setRight(), AudioBuffer< float >::setSize(), toString(), Rectangle< int >::transformedBy(), PixelARGB::unpremultiply(), Rectangle< int >::withBottom(), Range< int64 >::withEnd(), Rectangle< int >::withRight(), Line< ValueType >::withShortenedEnd(), and Line< ValueType >::withShortenedStart().

template<typename Type >

Type jmin	(	const Type	a,
		const Type	b,
		const Type	c
	)

Returns the smaller of three values.

template<typename Type >

Type jmin	(	const Type	a,
		const Type	b,
		const Type	c,
		const Type	d
	)

Returns the smaller of four values.

References jmin().

template<typename Type >

Type jmap	(	Type	value0To1,
		Type	targetRangeMin,
		Type	targetRangeMax
	)

Remaps a normalised value (between 0 and 1) to a target range.

This effectively returns (targetRangeMin + value0To1 * (targetRangeMax - targetRangeMin)).

template<typename Type >

Type jmap	(	Type	sourceValue,
		Type	sourceRangeMin,
		Type	sourceRangeMax,
		Type	targetRangeMin,
		Type	targetRangeMax
	)

Remaps a value from a source range to a target range.

References jassert.

template<typename Type >

Type findMinimum	(	const Type *	data,
		int	numValues
	)

Scans an array of values, returning the minimum value that it contains.

template<typename Type >

Type findMaximum	(	const Type *	values,
		int	numValues
	)

Scans an array of values, returning the maximum value that it contains.

template<typename Type >

void findMinAndMax	(	const Type *	values,
		int	numValues,
		Type &	lowest,
		Type &	highest
	)

Scans an array of values, returning the minimum and maximum values that it contains.

Referenced by AudioData::Pointer< SampleFormat, Endianness, InterleavingType, Constness >::findMinAndMax().

template<typename Type >

Type jlimit ( const Type  lowerLimit, const Type  upperLimit, const Type  valueToConstrain  )

noexcept

Constrains a value to keep it within a given range.

This will check that the specified value lies between the lower and upper bounds specified, and if not, will return the nearest value that would be in-range. Effectively, it's like calling jmax (lowerLimit, jmin (upperLimit, value)).

Note that it expects that lowerLimit <= upperLimit. If this isn't true, the results will be unpredictable.

Parameters

lowerLimit	the minimum value to return
upperLimit	the maximum value to return
valueToConstrain	the value to try to return

Returns

the closest value to valueToConstrain which lies between lowerLimit and upperLimit (inclusive)

See also

jmin, jmax, jmap

References jassert.

Referenced by Range< int64 >::clipValue(), Rectangle< int >::constrainedWithin(), Range< int64 >::constrainRange(), Line< ValueType >::findNearestProportionalPositionTo(), Rectangle< int >::getConstrainedPoint(), Draggable3DOrientation::getQuaternion(), ReferenceCountedArray< AudioProcessorGraph::Node >::removeRange(), OwnedArray< MidiBuffer >::removeRange(), Array< Button::Listener * >::removeRange(), and MidiEventList::toEventList().

template<typename Type >

bool isPositiveAndBelow ( Type  valueToTest, Type  upperLimit  )

noexcept

Returns true if a value is at least zero, and also below a specified upper limit.

This is basically a quicker way to write:

valueToTest >= 0 && valueToTest < upperLimit

References jassert.

Referenced by AudioBuffer< float >::addFrom(), AudioBuffer< float >::addFromWithRamp(), AudioBuffer< float >::addSample(), AudioBuffer< float >::applyGain(), AudioBuffer< float >::applyGainRamp(), PluginBusUtilities::busCanBeDisabled(), PluginBusUtilities::busIgnoresLayout(), AudioBuffer< float >::clear(), AudioBuffer< float >::copyFrom(), AudioBuffer< float >::copyFromWithRamp(), AudioBuffer< float >::findMinMax(), MidiEventList::getEvent(), AudioBuffer< float >::getMagnitude(), PluginBusUtilities::getNumChannels(), ReferenceCountedArray< AudioProcessorGraph::Node >::getObjectPointer(), ReferenceCountedArray< AudioProcessorGraph::Node >::getObjectPointerUnchecked(), SparseSet< int >::getRange(), AudioBuffer< float >::getReadPointer(), Array< Button::Listener * >::getReference(), AudioBuffer< float >::getRMSLevel(), AudioBuffer< float >::getSample(), OwnedArray< MidiBuffer >::getUnchecked(), Array< Button::Listener * >::getUnchecked(), AudioBuffer< float >::getWritePointer(), Array< Button::Listener * >::insert(), OwnedArray< MidiBuffer >::insertArray(), Array< Button::Listener * >::insertArray(), Array< Button::Listener * >::insertMultiple(), PluginBusUtilities::isBusEnabledByDefault(), EdgeTable::iterate(), ReferenceCountedArray< AudioProcessorGraph::Node >::move(), OwnedArray< MidiBuffer >::move(), Array< Button::Listener * >::move(), OwnedArray< MidiBuffer >::operator[](), Array< Button::Listener * >::operator[](), ReferenceCountedArray< AudioProcessorGraph::Node >::remove(), OwnedArray< MidiBuffer >::remove(), Array< Button::Listener * >::remove(), ReferenceCountedArray< AudioProcessorGraph::Node >::removeAndReturn(), OwnedArray< MidiBuffer >::removeAndReturn(), AudioBuffer< float >::reverse(), Array< Button::Listener * >::set(), AudioBuffer< float >::setSample(), Array< Button::Listener * >::setUnchecked(), ReferenceCountedArray< AudioProcessorGraph::Node >::swap(), OwnedArray< MidiBuffer >::swap(), and Array< Button::Listener * >::swap().

template<>

bool isPositiveAndBelow ( const int  valueToTest, const int  upperLimit  )

noexcept

References jassert.

template<typename Type >

bool isPositiveAndNotGreaterThan ( Type  valueToTest, Type  upperLimit  )

noexcept

Returns true if a value is at least zero, and also less than or equal to a specified upper limit.

This is basically a quicker way to write:

valueToTest >= 0 && valueToTest <= upperLimit

References jassert.

template<>

bool isPositiveAndNotGreaterThan ( const int  valueToTest, const int  upperLimit  )

noexcept

References jassert.

template<typename Type >

void swapVariables	(	Type &	variable1,
		Type &	variable2
	)

Handy function to swap two values.

template<typename Type1 >

void ignoreUnused ( const Type1 &  )

noexcept

Handy function for avoiding unused variables warning.

Referenced by OwnedArray< MidiBuffer >::addSorted(), UndoableAction::createCoalescedAction(), ContainerDeletePolicy< ObjectType >::destroy(), MidiInputCallback::handlePartialSysexMessage(), ReferenceCountedArray< AudioProcessorGraph::Node >::indexOfSorted(), OwnedArray< MidiBuffer >::indexOfSorted(), Array< Button::Listener * >::indexOfSorted(), numElementsInArray(), PositionableAudioSource::setLooping(), ReferenceCountedArray< AudioProcessorGraph::Node >::sort(), OwnedArray< MidiBuffer >::sort(), and Array< Button::Listener * >::sort().

template<typename Type1 , typename Type2 >

void ignoreUnused ( const Type1 &  , const Type2 &    )

noexcept

template<typename Type1 , typename Type2 , typename Type3 >

void ignoreUnused ( const Type1 &  , const Type2 &  , const Type3 &    )

noexcept

template<typename Type1 , typename Type2 , typename Type3 , typename Type4 >

void ignoreUnused ( const Type1 &  , const Type2 &  , const Type3 &  , const Type4 &    )

noexcept

template<typename Type , int N>

int numElementsInArray

(

Type(&)

array[N]

)

Handy function for getting the number of elements in a simple const C array.

E.g.

static int myArray[] = { 1, 2, 3 };

int numElements = numElementsInArray (myArray) // returns 3

References ignoreUnused().

Referenced by AudioBuffer< float >::reverse().

template<typename Type >

Type juce_hypot ( Type  a, Type  b  )

noexcept

Using juce_hypot is easier than dealing with the different types of hypot function that are provided by the various platforms and compilers.

Referenced by Point< int >::getDistanceFrom(), Point< int >::getDistanceFromOrigin(), and Line< ValueType >::getPointAlongLine().

int64 abs64 ( const int64  n )

noexcept

64-bit abs function.

float degreesToRadians ( float  degrees )

noexcept

Converts an angle in degrees to radians.

double degreesToRadians ( double  degrees )

noexcept

Converts an angle in degrees to radians.

float radiansToDegrees ( float  radians )

noexcept

Converts an angle in radians to degrees.

References float_Pi.

double radiansToDegrees ( double  radians )

noexcept

Converts an angle in radians to degrees.

References double_Pi.

template<typename NumericType >

bool juce_isfinite ( NumericType  )

noexcept

The isfinite() method seems to vary between platforms, so this is a platform-independent function for it.

Referenced by StatisticsAccumulator< FloatType >::addValue(), Point< int >::isFinite(), and Rectangle< int >::isFinite().

template<>

bool juce_isfinite ( float  value )

noexcept

template<>

bool juce_isfinite ( double  value )

noexcept

template<typename FloatType >

int roundToInt ( const FloatType  value )

noexcept

Fast floating-point-to-integer conversion.

This is faster than using the normal c++ cast to convert a float to an int, and it will round the value to the nearest integer, rather than rounding it down like the normal cast does.

Note that this routine gets its speed at the expense of some accuracy, and when rounding values whose floating point component is exactly 0.5, odd numbers and even numbers will be rounded up or down differently.

Referenced by AudioParameterInt::get(), AudioParameterChoice::getIndex(), roundDoubleToInt(), roundFloatToInt(), Point< int >::roundToInt(), roundToIntAccurate(), MidiEventList::toEventList(), and Rectangle< int >::toNearestInt().

int roundToInt ( int  value )

noexcept

int roundToIntAccurate ( const double  value )

noexcept

Fast floating-point-to-integer conversion.

This is a slightly slower and slightly more accurate version of roundDoubleToInt(). It works fine for values above zero, but negative numbers are rounded the wrong way.

References roundToInt().

int roundDoubleToInt ( const double  value )

noexcept

Fast floating-point-to-integer conversion.

This is faster than using the normal c++ cast to convert a double to an int, and it will round the value to the nearest integer, rather than rounding it down like the normal cast does.

Note that this routine gets its speed at the expense of some accuracy, and when rounding values whose floating point component is exactly 0.5, odd numbers and even numbers will be rounded up or down differently. For a more accurate conversion, see roundDoubleToIntAccurate().

References roundToInt().

int roundFloatToInt ( const float  value )

noexcept

Fast floating-point-to-integer conversion.

This is faster than using the normal c++ cast to convert a float to an int, and it will round the value to the nearest integer, rather than rounding it down like the normal cast does.

Note that this routine gets its speed at the expense of some accuracy, and when rounding values whose floating point component is exactly 0.5, odd numbers and even numbers will be rounded up or down differently.

References roundToInt().

template<typename IntegerType >

bool isPowerOfTwo

(

IntegerType

value

)

Returns true if the specified integer is a power-of-two.

int nextPowerOfTwo ( int  n )

noexcept

Returns the smallest power-of-two which is equal to or greater than the given integer.

int countNumberOfBits ( uint32  n )

noexcept

Returns the number of bits in a 32-bit integer.

Referenced by countNumberOfBits().

int countNumberOfBits ( uint64  n )

noexcept

Returns the number of bits in a 64-bit integer.

References countNumberOfBits().

template<typename IntegerType >

IntegerType negativeAwareModulo ( IntegerType  dividend, const IntegerType  divisor  )

noexcept

Performs a modulo operation, but can cope with the dividend being negative.

The divisor must be greater than zero.

References jassert.

template<typename NumericType >

NumericType square ( NumericType  n )

noexcept

Returns the square of its argument.

Variable Documentation

const double double_Pi = 3.1415926535897932384626433832795

A predefined value for Pi, at double-precision.

See also

float_Pi

Referenced by radiansToDegrees().

const float float_Pi = 3.14159265358979323846f

A predefined value for Pi, at single-precision.

See also

double_Pi

Referenced by radiansToDegrees().