/* ============================================================================== This file is part of the JUCE library - "Jules' Utility Class Extensions" Copyright 2004-11 by Raw Material Software Ltd. ------------------------------------------------------------------------------ JUCE can be redistributed and/or modified under the terms of the GNU General Public License (Version 2), as published by the Free Software Foundation. A copy of the license is included in the JUCE distribution, or can be found online at www.gnu.org/licenses. JUCE is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. ------------------------------------------------------------------------------ To release a closed-source product which uses JUCE, commercial licenses are available: visit www.rawmaterialsoftware.com/juce for more information. ============================================================================== */ #ifndef __JUCE_MATHSFUNCTIONS_JUCEHEADER__ #define __JUCE_MATHSFUNCTIONS_JUCEHEADER__ //============================================================================== /* This file sets up some handy mathematical typdefs and functions. */ //============================================================================== // Definitions for the int8, int16, int32, int64 and pointer_sized_int types. /** A platform-independent 8-bit signed integer type. */ typedef signed char int8; /** A platform-independent 8-bit unsigned integer type. */ typedef unsigned char uint8; /** A platform-independent 16-bit signed integer type. */ typedef signed short int16; /** A platform-independent 16-bit unsigned integer type. */ typedef unsigned short uint16; /** A platform-independent 32-bit signed integer type. */ typedef signed int int32; /** A platform-independent 32-bit unsigned integer type. */ typedef unsigned int uint32; #if JUCE_MSVC /** A platform-independent 64-bit integer type. */ typedef __int64 int64; /** A platform-independent 64-bit unsigned integer type. */ typedef unsigned __int64 uint64; /** A platform-independent macro for writing 64-bit literals, needed because different compilers have different syntaxes for this. E.g. writing literal64bit (0x1000000000) will translate to 0x1000000000LL for GCC, or 0x1000000000 for MSVC. */ #define literal64bit(longLiteral) ((__int64) longLiteral) #else /** A platform-independent 64-bit integer type. */ typedef long long int64; /** A platform-independent 64-bit unsigned integer type. */ typedef unsigned long long uint64; /** A platform-independent macro for writing 64-bit literals, needed because different compilers have different syntaxes for this. E.g. writing literal64bit (0x1000000000) will translate to 0x1000000000LL for GCC, or 0x1000000000 for MSVC. */ #define literal64bit(longLiteral) (longLiteral##LL) #endif #if JUCE_64BIT /** A signed integer type that's guaranteed to be large enough to hold a pointer without truncating it. */ typedef int64 pointer_sized_int; /** An unsigned integer type that's guaranteed to be large enough to hold a pointer without truncating it. */ typedef uint64 pointer_sized_uint; #elif JUCE_MSVC /** A signed integer type that's guaranteed to be large enough to hold a pointer without truncating it. */ typedef _W64 int pointer_sized_int; /** An unsigned integer type that's guaranteed to be large enough to hold a pointer without truncating it. */ typedef _W64 unsigned int pointer_sized_uint; #else /** A signed integer type that's guaranteed to be large enough to hold a pointer without truncating it. */ typedef int pointer_sized_int; /** An unsigned integer type that's guaranteed to be large enough to hold a pointer without truncating it. */ typedef unsigned int pointer_sized_uint; #endif #if JUCE_MSVC typedef pointer_sized_int ssize_t; #endif //============================================================================== // Some indispensible min/max functions /** Returns the larger of two values. */ template inline Type jmax (const Type a, const Type b) { return (a < b) ? b : a; } /** Returns the larger of three values. */ template inline Type jmax (const Type a, const Type b, const Type c) { return (a < b) ? ((b < c) ? c : b) : ((a < c) ? c : a); } /** Returns the larger of four values. */ template inline Type jmax (const Type a, const Type b, const Type c, const Type d) { return jmax (a, jmax (b, c, d)); } /** Returns the smaller of two values. */ template inline Type jmin (const Type a, const Type b) { return (b < a) ? b : a; } /** Returns the smaller of three values. */ template inline Type jmin (const Type a, const Type b, const Type c) { return (b < a) ? ((c < b) ? c : b) : ((c < a) ? c : a); } /** Returns the smaller of four values. */ template inline Type jmin (const Type a, const Type b, const Type c, const Type d) { return jmin (a, jmin (b, c, d)); } /** Scans an array of values, returning the minimum value that it contains. */ template const Type findMinimum (const Type* data, int numValues) { if (numValues <= 0) return Type(); Type result (*data++); while (--numValues > 0) // (> 0 rather than >= 0 because we've already taken the first sample) { const Type& v = *data++; if (v < result) result = v; } return result; } /** Scans an array of values, returning the maximum value that it contains. */ template const Type findMaximum (const Type* values, int numValues) { if (numValues <= 0) return Type(); Type result (*values++); while (--numValues > 0) // (> 0 rather than >= 0 because we've already taken the first sample) { const Type& v = *values++; if (result < v) result = v; } return result; } /** Scans an array of values, returning the minimum and maximum values that it contains. */ template void findMinAndMax (const Type* values, int numValues, Type& lowest, Type& highest) { if (numValues <= 0) { lowest = Type(); highest = Type(); } else { Type mn (*values++); Type mx (mn); while (--numValues > 0) // (> 0 rather than >= 0 because we've already taken the first sample) { const Type& v = *values++; if (mx < v) mx = v; if (v < mn) mn = v; } lowest = mn; highest = mx; } } //============================================================================== /** 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. @param lowerLimit the minimum value to return @param upperLimit the maximum value to return @param valueToConstrain the value to try to return @returns the closest value to valueToConstrain which lies between lowerLimit and upperLimit (inclusive) @see jlimit0To, jmin, jmax */ template inline Type jlimit (const Type lowerLimit, const Type upperLimit, const Type valueToConstrain) noexcept { jassert (lowerLimit <= upperLimit); // if these are in the wrong order, results are unpredictable.. return (valueToConstrain < lowerLimit) ? lowerLimit : ((upperLimit < valueToConstrain) ? upperLimit : valueToConstrain); } /** Returns true if a value is at least zero, and also below a specified upper limit. This is basically a quicker way to write: @code valueToTest >= 0 && valueToTest < upperLimit @endcode */ template inline bool isPositiveAndBelow (Type valueToTest, Type upperLimit) noexcept { jassert (Type() <= upperLimit); // makes no sense to call this if the upper limit is itself below zero.. return Type() <= valueToTest && valueToTest < upperLimit; } template <> inline bool isPositiveAndBelow (const int valueToTest, const int upperLimit) noexcept { jassert (upperLimit >= 0); // makes no sense to call this if the upper limit is itself below zero.. return static_cast (valueToTest) < static_cast (upperLimit); } /** 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: @code valueToTest >= 0 && valueToTest <= upperLimit @endcode */ template inline bool isPositiveAndNotGreaterThan (Type valueToTest, Type upperLimit) noexcept { jassert (Type() <= upperLimit); // makes no sense to call this if the upper limit is itself below zero.. return Type() <= valueToTest && valueToTest <= upperLimit; } template <> inline bool isPositiveAndNotGreaterThan (const int valueToTest, const int upperLimit) noexcept { jassert (upperLimit >= 0); // makes no sense to call this if the upper limit is itself below zero.. return static_cast (valueToTest) <= static_cast (upperLimit); } //============================================================================== /** Handy function to swap two values. */ template inline void swapVariables (Type& variable1, Type& variable2) { std::swap (variable1, variable2); } /** Handy function for getting the number of elements in a simple const C array. E.g. @code static int myArray[] = { 1, 2, 3 }; int numElements = numElementsInArray (myArray) // returns 3 @endcode */ template inline int numElementsInArray (Type (&array)[N]) { (void) array; // (required to avoid a spurious warning in MS compilers) (void) sizeof (0[array]); // This line should cause an error if you pass an object with a user-defined subscript operator return N; } //============================================================================== // Some useful maths functions that aren't always present with all compilers and build settings. /** Using juce_hypot is easier than dealing with the different types of hypot function that are provided by the various platforms and compilers. */ template inline Type juce_hypot (Type a, Type b) noexcept { #if JUCE_MSVC return static_cast (_hypot (a, b)); #else return static_cast (hypot (a, b)); #endif } /** 64-bit abs function. */ inline int64 abs64 (const int64 n) noexcept { return (n >= 0) ? n : -n; } //============================================================================== /** A predefined value for Pi, at double-precision. @see float_Pi */ const double double_Pi = 3.1415926535897932384626433832795; /** A predefined value for Pi, at sngle-precision. @see double_Pi */ const float float_Pi = 3.14159265358979323846f; //============================================================================== /** The isfinite() method seems to vary between platforms, so this is a platform-independent function for it. */ template inline bool juce_isfinite (FloatingPointType value) { #if JUCE_WINDOWS return _finite (value); #elif JUCE_ANDROID return isfinite (value); #else return std::isfinite (value); #endif } //============================================================================== #if JUCE_MSVC #pragma optimize ("t", off) #pragma float_control (precise, on, push) #endif /** 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. */ template inline int roundToInt (const FloatType value) noexcept { union { int asInt[2]; double asDouble; } n; n.asDouble = ((double) value) + 6755399441055744.0; #if JUCE_BIG_ENDIAN return n.asInt [1]; #else return n.asInt [0]; #endif } #if JUCE_MSVC #pragma float_control (pop) #pragma optimize ("", on) // resets optimisations to the project defaults #endif /** 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. */ inline int roundToIntAccurate (const double value) noexcept { return roundToInt (value + 1.5e-8); } /** 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(). */ inline int roundDoubleToInt (const double value) noexcept { return roundToInt (value); } /** 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. */ inline int roundFloatToInt (const float value) noexcept { return roundToInt (value); } //============================================================================== /** Returns true if the specified integer is a power-of-two. */ template bool isPowerOfTwo (IntegerType value) { return (value & (value - 1)) == 0; } /** Returns the smallest power-of-two which is equal to or greater than the given integer. */ inline int nextPowerOfTwo (int n) noexcept { --n; n |= (n >> 1); n |= (n >> 2); n |= (n >> 4); n |= (n >> 8); n |= (n >> 16); return n + 1; } /** Performs a modulo operation, but can cope with the dividend being negative. The divisor must be greater than zero. */ template int negativeAwareModulo (IntegerType dividend, const IntegerType divisor) noexcept { jassert (divisor > 0); dividend %= divisor; return (dividend < 0) ? (dividend + divisor) : dividend; } //============================================================================== #if (JUCE_INTEL && JUCE_32BIT) || defined (DOXYGEN) /** 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. */ #define JUCE_UNDENORMALISE(x) x += 1.0f; x -= 1.0f; #else #define JUCE_UNDENORMALISE(x) #endif //============================================================================== /** This namespace contains a few template classes for helping work out class type variations. */ namespace TypeHelpers { #if JUCE_VC8_OR_EARLIER #define PARAMETER_TYPE(type) const type& #else /** The ParameterType struct is used to find the best type to use when passing some kind of object as a parameter. Of course, this is only likely to be useful in certain esoteric template situations. Because "typename TypeHelpers::ParameterType::type" is a bit of a mouthful, there's a PARAMETER_TYPE(SomeClass) macro that you can use to get the same effect. E.g. "myFunction (PARAMETER_TYPE (int), PARAMETER_TYPE (MyObject))" would evaluate to "myfunction (int, const MyObject&)", keeping any primitive types as pass-by-value, but passing objects as a const reference, to avoid copying. */ template struct ParameterType { typedef const Type& type; }; #if ! DOXYGEN template struct ParameterType { typedef Type& type; }; template struct ParameterType { typedef Type* type; }; template <> struct ParameterType { typedef char type; }; template <> struct ParameterType { typedef unsigned char type; }; template <> struct ParameterType { typedef short type; }; template <> struct ParameterType { typedef unsigned short type; }; template <> struct ParameterType { typedef int type; }; template <> struct ParameterType { typedef unsigned int type; }; template <> struct ParameterType { typedef long type; }; template <> struct ParameterType { typedef unsigned long type; }; template <> struct ParameterType { typedef int64 type; }; template <> struct ParameterType { typedef uint64 type; }; template <> struct ParameterType { typedef bool type; }; template <> struct ParameterType { typedef float type; }; template <> struct ParameterType { typedef double type; }; #endif /** A helpful macro to simplify the use of the ParameterType template. @see ParameterType */ #define PARAMETER_TYPE(a) typename TypeHelpers::ParameterType::type #endif /** 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. */ template struct SmallestFloatType { typedef float type; }; template <> struct SmallestFloatType { typedef double type; }; } //============================================================================== #endif // __JUCE_MATHSFUNCTIONS_JUCEHEADER__