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FMath

Structure for all math helper functions, inherits from platform math to pick up platform-specific implementations Check GenericPlatformMath.h for additional math functions

API > API/Runtime > API/Runtime/Core

Structure for all math helper functions, inherits from platform math to pick up platform-specific implementations Check GenericPlatformMath.h for additional math functions

   
Name FMath
Type struct
Header File /Engine/Source/Runtime/Core/Public/Math/UnrealMathUtility.h
Include Path #include "Math/UnrealMathUtility.h"

Syntax

struct FMath : public FLinuxPlatformMath

Inheritance Hierarchy

Constants

Name Type Remarks Include Path
BitFlag const uint32 32 bit values where BitFlag[x] == (1< Math/UnrealMathUtility.h

Functions

Public

Name Remarks Include Path Unreal Specifiers

bool IntersectPlanes2 ( UE::Math::TVector< T >& I,
UE::Math::TVector< T >& D,
const UE::Math::TPlane< T >& P1,
const UE::Math::TPlane< T >& P2
)

   Math/Plane.h  

bool IntersectPlanes3 ( UE::Math::TVector< T >& I,
const UE::Math::TPlane< T >& P1,
const UE::Math::TPlane< T >& P2,
const UE::Math::TPlane< T >& P3
)

   Math/Plane.h  

UE::Math::TVector< T > LinePlaneIntersection ( const UE::Math::TVector< T >& Point1,
const UE::Math::TVector< T >& Point2,
const UE::Math::TPlane< T >& Plane
)

   Math/Plane.h  

UE::Math::TVector< T > LinePlaneIntersection ( const UE::Math::TVector< T >& Point1,
const UE::Math::TVector< T >& Point2,
const UE::Math::TVector< T >& PlaneOrigin,
const UE::Math::TVector< T >& PlaneNormal
)

 FMath inline functions Math/Vector.h  

bool LineSphereIntersection ( const UE::Math::TVector< T >& Start,
const UE::Math::TVector< T >& Dir,
T Length,
const UE::Math::TVector< T >& Origin,
T Radius
)

   Math/Vector.h  

UE::Math::TVector< T > RayPlaneIntersection ( const UE::Math::TVector< T >& RayOrigin,
const UE::Math::TVector< T >& RayDirection,
const UE::Math::TPlane< T >& Plane
)

 FMath inline functions Math/Plane.h  

T RayPlaneIntersectionParam ( const UE::Math::TVector< T >& RayOrigin,
const UE::Math::TVector< T >& RayDirection,
const UE::Math::TPlane< T >& Plane
)

   Math/Plane.h  

Static

Name Remarks Include Path Unreal Specifiers

static void ApplyScaleToFloat ( float& Dst,
const FVector& DeltaScale,
float Magnitude
)

 Handy to apply scaling in the editor Math/UnrealMathUtility.h  

static T BiLerp ( const T& P00,
const T& P10,
const T& P01,
const T& P11,
const U& FracX,
const U& FracY
)

 Custom lerps defined for those classes not suited to the default implemenation. Math/UnrealMathUtility.h  

static T BiLerp ( const T& P00,
const T& P10,
const T& P01,
const T& P11,
const U& FracX,
const U& FracY
)

 Performs a 2D linear interpolation between four values values, FracX, FracY ranges from 0-1 Math/UnrealMathUtility.h  

static void CartesianToPolar ( const T X,
const T Y,
T& OutRad,
T& OutAng
)

 Converts given Cartesian coordinate pair to Polar coordinate system. Math/UnrealMathUtility.h  

static void CartesianToPolar ( const UE::Math::TVector2< T > InCart,
UE::Math::TVector2< T >& OutPolar
)

 Converts given Cartesian coordinate pair to Polar coordinate system. Math/UnrealMathUtility.h  

static FLinearColor CInterpTo ( const FLinearColor& Current,
const FLinearColor& Target,
float DeltaTime,
float InterpSpeed
)

 Interpolate Linear Color from Current to Target. Math/UnrealMathUtility.h  

static int64 Clamp ( const int64 X,
const int32 Min,
const int32 Max
)

 Clamps X to be between Min and Max, inclusive. Overload to support mixed int64/int32 types. Math/UnrealMathUtility.h  

static double Clamp ( const double X,
const double Min,
const double Max
)

   Math/UnrealMathUtility.h  

static float Clamp ( const float X,
const float Min,
const float Max
)

 Clamps X to be between Min and Max, inclusive. Math/UnrealMathUtility.h  

static decltype(X *Y *Z) Clamp ( Arg1 X,
Arg2 Y,
Arg3 Z
)

 Allow mixing float/double arguments, promoting to highest precision type. Math/UnrealMathUtility.h  

static T Clamp ( const T X,
const T MinValue,
const T MaxValue
)

 Clamps X to be between Min and Max, inclusive Math/UnrealMathUtility.h  

static T ClampAngle ( T AngleDegrees,
T MinAngleDegrees,
T MaxAngleDegrees
)

 Clamps an arbitrary angle to be between the given angles. Will clamp to nearest boundary. Math/UnrealMathUtility.h  

static decltype(X *Y *Z) ClampAngle ( Arg1 X,
Arg2 Y,
Arg3 Z
)

   Math/UnrealMathUtility.h  

static FVector ClosestPointOnInfiniteLine ( const FVector& LineStart,
const FVector& LineEnd,
const FVector& Point
)

 Find the point on the infinite line between two points (LineStart, LineEnd) which is closest to Point Math/UnrealMathUtility.h  

static UE::Math::TVector< T > ClosestPointOnLine ( const UE::Math::TVector< T >& LineStart,
const UE::Math::TVector< T >& LineEnd,
const UE::Math::TVector< T >& Point
)

 Find the point on the line segment from LineStart to LineEnd which is closest to Point Math/UnrealMathUtility.h  

static UE::Math::TVector< T > ClosestPointOnSegment ( const UE::Math::TVector< T >& Point,
const UE::Math::TVector< T >& StartPoint,
const UE::Math::TVector< T >& EndPoint
)

 Returns closest point on a segment to a given point. Math/UnrealMathUtility.h  

static UE::Math::TVector2< T > ClosestPointOnSegment2D ( const UE::Math::TVector2< T >& Point,
const UE::Math::TVector2< T >& StartPoint,
const UE::Math::TVector2< T >& EndPoint
)

 FVector2D version of ClosestPointOnSegment. Math/UnrealMathUtility.h  

static FVector ClosestPointOnTetrahedronToPoint ( const FVector& Point,
const FVector& A,
const FVector& B,
const FVector& C,
const FVector& D
)

 Returns closest point on a tetrahedron to a point. Math/UnrealMathUtility.h  

static FVector ClosestPointOnTriangleToPoint ( const FVector& Point,
const FVector& A,
const FVector& B,
const FVector& C
)

 Returns closest point on a triangle to a point. Math/UnrealMathUtility.h  

static FVector ComputeBaryCentric2D ( const FVector& Point,
const FVector& A,
const FVector& B,
const FVector& C
)

 Computes the barycentric coordinates for a given point in a 3D triangle. Math/UnrealMathUtility.h  

static FVector4 ComputeBaryCentric3D ( const FVector& Point,
const FVector& A,
const FVector& B,
const FVector& C,
const FVector& D
)

 Computes the barycentric coordinates for a given point on a tetrahedron (3D) Math/UnrealMathUtility.h  

static bool ComputeBarycentricTri ( const FVector& Point,
const FVector& A,
const FVector& B,
const FVector& C,
FVector& OutBarycentric,
double Tolerance
)

 Computes the barycentric coordinates for a given point in a triangle Math/UnrealMathUtility.h  

static UE::Math::TSphere< FReal > ComputeBoundingSphereForCone ( UE::Math::TVector< FReal > const& ConeOrigin,
UE::Math::TVector< FReal > const& ConeDirection,
FReal ConeRadius,
FReal CosConeAngle,
FReal SinConeAngle
)

 FMath inline functions Computes minimal bounding sphere encompassing given cone Math/UnrealMathUtility.h  

static uint32 ComputeProjectedSphereScissorRect ( FIntRect& InOutScissorRect,
FVector SphereOrigin,
float Radius,
FVector ViewOrigin,
const FMatrix& ViewMatrix,
const FMatrix& ProjMatrix
)

 @parma InOutScissorRect should be set to View.ViewRect before the call Math/UnrealMathUtility.h  

static void CriticallyDampedSmoothing ( T& InOutValue,
T& InOutValueRate,
const T& InTargetValue,
const T& InTargetValueRate,
const float InDeltaTime,
const float InSmoothingTime
)

 Smooths a value using a critically damped spring. Math/UnrealMathUtility.h  

static T Cube ( const T A
)

 Cubes the value Math/UnrealMathUtility.h  

static U CubicCRSplineInterp ( const U& P0,
const U& P1,
const U& P2,
const U& P3,
const float T0,
const float T1,
const float T2,
const float T3,
const float T
)

 Cubic Catmull-Rom Spline interpolation. Math/UnrealMathUtility.h  

static U CubicCRSplineInterpSafe ( const U& P0,
const U& P1,
const U& P2,
const U& P3,
const float T0,
const float T1,
const float T2,
const float T3,
const float T
)

 Same as CubicCRSplineInterp but with additional saftey checks. If the checks fail P1 is returned. Math/UnrealMathUtility.h  

static T CubicInterp ( const T& P0,
const T& T0,
const T& P1,
const T& T1,
const U& A
)

 Custom lerps defined for those classes not suited to the default implemenation. Math/UnrealMathUtility.h  

static T CubicInterp ( const T& P0,
const T& T0,
const T& P1,
const T& T1,
const U& A
)

 Performs a cubic interpolation Math/UnrealMathUtility.h  

static T CubicInterpDerivative ( const T& P0,
const T& T0,
const T& P1,
const T& T1,
const U& A
)

 Performs a first derivative cubic interpolation Math/UnrealMathUtility.h  

static T CubicInterpSecondDerivative ( const T& P0,
const T& T0,
const T& P1,
const T& T1,
const U& A
)

 Performs a second derivative cubic interpolation Math/UnrealMathUtility.h  

static double DegreesToRadians ( double const& DegVal
)

   Math/UnrealMathUtility.h  

static float DegreesToRadians ( float const& DegVal
)

   Math/UnrealMathUtility.h  

static decltype(DegVal *((3.1415926535897932f)/180.f)) DegreesToRadians ( T const& DegVal
)

 Converts degrees to radians. Math/UnrealMathUtility.h  

static T DivideAndRoundDown ( T Dividend,
T Divisor
)

 Divides two integers and rounds down Math/UnrealMathUtility.h  

static T DivideAndRoundNearest ( T Dividend,
T Divisor
)

 Divides two integers and rounds to nearest Math/UnrealMathUtility.h  

static T DivideAndRoundUp ( T Dividend,
T Divisor
)

 Divides two integers and rounds up Math/UnrealMathUtility.h  

static T DynamicWeightedMovingAverage ( T CurrentSample,
T PreviousSample,
T MaxDistance,
T MinWeight,
T MaxWeight
)

 Calculates the new value in a weighted moving average series using the previous value and a weight range. Math/UnrealMathUtility.h  

static bool Eval ( FString Str,
float& OutValue
)

 Evaluates a numerical equation. Math/UnrealMathUtility.h  

static void ExponentialSmoothingApprox ( T& InOutValue,
const T& InTargetValue,
const float InDeltaTime,
const float InSmoothingTime
)

 Smooths a value using exponential damping towards a target. Math/UnrealMathUtility.h  

static bool ExtractBoolFromBitfield ( const uint8* Ptr,
uint32 Index
)

 Get a bit in memory created from bitflags (uint32 Value:1), used for EngineShowFlags, TestBitFieldFunctions() tests the implementation Math/UnrealMathUtility.h  

static float FastAsin ( float Value
)

 Computes the ASin of a scalar value. Math/UnrealMathUtility.h  

static double FastAsin ( double Value
)

   Math/UnrealMathUtility.h  

static decltype(A1 - A2) FindDeltaAngleDegrees ( T A1,
T2 A2
)

 Find the smallest angle between two headings (in degrees) Math/UnrealMathUtility.h  

static decltype(A1 - A2) FindDeltaAngleRadians ( T A1,
T2 A2
)

 Find the smallest angle between two headings (in radians) Math/UnrealMathUtility.h  

static auto FInterpConstantTo ( T1 Current,
T2 Target,
T3 DeltaTime,
T4 InterpSpeed
)

 Interpolate float from Current to Target with constant step Math/UnrealMathUtility.h  

static auto FInterpTo ( T1 Current,
T2 Target,
T3 DeltaTime,
T4 InterpSpeed
)

 Interpolate float from Current to Target. Math/UnrealMathUtility.h  

static float FixedTurn ( float InCurrent,
float InDesired,
float InDeltaRate
)

 Returns a new rotation component value Math/UnrealMathUtility.h  

static float Floor ( float F
)

 Converts a float to a nearest less or equal integer. Math/UnrealMathUtility.h  

static double Floor ( double F
)

 Converts a double to a nearest less or equal integer. Math/UnrealMathUtility.h  

static IntegralType Floor ( IntegralType I
)

 Converts an integral type to a nearest less or equal integer. Math/UnrealMathUtility.h  

static FString FormatIntToHumanReadable ( int32 Val
)

 Formats an integer value into a human readable string (i.e. 12345 becomes "12,345") Math/UnrealMathUtility.h  

static float FRandRange ( float InMin,
float InMax
)

 Util to generate a random number in a range. Math/UnrealMathUtility.h  

static decltype(X *Y) FRandRange ( Arg1 X,
Arg2 Y
)

   Math/UnrealMathUtility.h  

static double FRandRange ( double InMin,
double InMax
)

 Util to generate a random number in a range. Math/UnrealMathUtility.h  

static FVector2D GetAzimuthAndElevation ( const FVector& Direction,
const FVector& AxisX,
const FVector& AxisY,
const FVector& AxisZ
)

 Returns Azimuth and Elevation of vector 'Direction' in coordinate system O(AxisX,AxisY,AxisZ). Math/UnrealMathUtility.h  

static FVector GetBaryCentric2D ( const FVector2D& Point,
const FVector2D& A,
const FVector2D& B,
const FVector2D& C
)

 Computes the barycentric coordinates for a given point in a triangle - simpler than the Compute versions Math/UnrealMathUtility.h  

static FVector GetBaryCentric2D ( const FVector& Point,
const FVector& A,
const FVector& B,
const FVector& C
)

 Computes the barycentric coordinates for a given point in a triangle, only considering the XY coordinates - simpler than the Compute versions Math/UnrealMathUtility.h  

static bool GetDistanceWithinConeSegment ( FVector Point,
FVector ConeStartPoint,
FVector ConeLine,
float RadiusAtStart,
float RadiusAtEnd,
float& PercentageOut
)

 Calculates whether a Point is within a cone segment, and also what percentage within the cone (100% is along the center line, whereas 0% is along the edge) Math/UnrealMathUtility.h  

static bool GetDotDistance ( FVector2D& OutDotDist,
const FVector& Direction,
const FVector& AxisX,
const FVector& AxisY,
const FVector& AxisZ
)

 Calculates the dotted distance of vector 'Direction' to coordinate system O(AxisX,AxisY,AxisZ). Math/UnrealMathUtility.h  

static auto GetMappedRangeValueClamped ( const UE::Math::TVector2< T >& InputRange,
const UE::Math::TVector2< T >& OutputRange,
const T2 Value
)

 For the given Value clamped to the [Input:Range] inclusive, returns the corresponding percentage in [Output:Range] Inclusive. Math/UnrealMathUtility.h  

static T GetMappedRangeValueClamped ( const TRange< T >& InputRange,
const TRange< T >& OutputRange,
const T Value
)

   Math/UnrealMathUtility.h  

static auto GetMappedRangeValueUnclamped ( const UE::Math::TVector2< T >& InputRange,
const UE::Math::TVector2< T >& OutputRange,
const T2 Value
)

 Transform the given Value relative to the input range to the Output Range. Math/UnrealMathUtility.h  

static auto GetRangePct ( T MinValue,
T MaxValue,
T2 Value
)

 Calculates the percentage along a line from MinValue to MaxValue that Value is. Math/UnrealMathUtility.h  

static double GetRangePct ( TRange< T > const& Range,
T Value
)

   Math/UnrealMathUtility.h  

static auto GetRangePct ( UE::Math::TVector2< T > const& Range,
T2 Value
)

 Same as above, but taking a 2d vector as the range. Math/UnrealMathUtility.h  

static T GetRangeValue ( TRange< T > const& Range,
T Pct
)

   Math/UnrealMathUtility.h  

static auto GetRangeValue ( UE::Math::TVector2< T > const& Range,
T2 Pct
)

 Basically a Vector2d version of Lerp. Math/UnrealMathUtility.h  

static FVector GetReflectionVector ( const FVector& Direction,
const FVector& SurfaceNormal
)

 Given a direction vector and a surface normal, returns the vector reflected across the surface normal. Math/UnrealMathUtility.h  

static float GetTForSegmentPlaneIntersect ( const FVector& StartPoint,
const FVector& EndPoint,
const FPlane& Plane
)

 Returns the time (t) of the intersection of the passed segment and a plane (could be <0 or >1) Math/UnrealMathUtility.h  

static int32 GreatestCommonDivisor ( int32 a,
int32 b
)

 Use the Euclidean method to find the GCD. Math/UnrealMathUtility.h  

static decltype(X *Y) GridSnap ( Arg1 X,
Arg2 Y
)

 Allow mixing float/double arguments, promoting to highest precision type. Math/UnrealMathUtility.h  

static T GridSnap ( T Location,
T Grid
)

 Snaps a value to the nearest grid multiple Math/UnrealMathUtility.h  

static T InterpCircularIn ( const T& A,
const T& B,
float Alpha
)

 Interpolation between A and B, applying a circular in function. Math/UnrealMathUtility.h  

static T InterpCircularInOut ( const T& A,
const T& B,
float Alpha
)

 Interpolation between A and B, applying a circular in/out function. Math/UnrealMathUtility.h  

static T InterpCircularOut ( const T& A,
const T& B,
float Alpha
)

 Interpolation between A and B, applying a circular out function. Math/UnrealMathUtility.h  

static T InterpEaseIn ( const T& A,
const T& B,
float Alpha,
float Exp
)

 Interpolate between A and B, applying an ease in function. Exp controls the degree of the curve. Math/UnrealMathUtility.h  

static T InterpEaseInOut ( const T& A,
const T& B,
float Alpha,
float Exp
)

 Interpolate between A and B, applying an ease in/out function. Math/UnrealMathUtility.h  

static T InterpEaseOut ( const T& A,
const T& B,
float Alpha,
float Exp
)

 Interpolate between A and B, applying an ease out function. Exp controls the degree of the curve. Math/UnrealMathUtility.h  

static T InterpExpoIn ( const T& A,
const T& B,
float Alpha
)

 Interpolation between A and B, applying an exponential in function. Math/UnrealMathUtility.h  

static T InterpExpoInOut ( const T& A,
const T& B,
float Alpha
)

 Interpolation between A and B, applying an exponential in/out function. Math/UnrealMathUtility.h  

static T InterpExpoOut ( const T& A,
const T& B,
float Alpha
)

 Interpolation between A and B, applying an exponential out function. Math/UnrealMathUtility.h  

static T InterpSinIn ( const T& A,
const T& B,
float Alpha
)

 Interpolation between A and B, applying a sinusoidal in function. Math/UnrealMathUtility.h  

static T InterpSinInOut ( const T& A,
const T& B,
float Alpha
)

 Interpolation between A and B, applying a sinusoidal in/out function. Math/UnrealMathUtility.h  

static T InterpSinOut ( const T& A,
const T& B,
float Alpha
)

 Interpolation between A and B, applying a sinusoidal out function. Math/UnrealMathUtility.h  

static T InterpStep ( const T& A,
const T& B,
float Alpha,
int32 Steps
)

 Interpolation between A and B, applying a step function. Math/UnrealMathUtility.h  

static bool IntersectPlanes2 ( UE::Math::TVector< FReal >& I,
UE::Math::TVector< FReal >& D,
const UE::Math::TPlane< FReal >& P1,
const UE::Math::TPlane< FReal >& P2
)

 Compute intersection point and direction of line joining two planes. Math/UnrealMathUtility.h  

static bool IntersectPlanes3 ( UE::Math::TVector< FReal >& I,
const UE::Math::TPlane< FReal >& P1,
const UE::Math::TPlane< FReal >& P2,
const UE::Math::TPlane< FReal >& P3
)

 Compute intersection point of three planes. Return 1 if valid, 0 if infinite. Math/UnrealMathUtility.h  

static T InvExpApprox ( T X
)

 Returns an approximation of Exp(-X) based on a Taylor expansion that has had the coefficients adjusted (using optimisation) to minimise the error in the range 0 < X < 1, which is below 0.1%. Math/UnrealMathUtility.h  

static bool IsNearlyEqual ( Arg1 X,
Arg2 Y,
Arg3 Z
)

   Math/UnrealMathUtility.h  

static bool IsNearlyEqual ( float A,
float B,
float ErrorTolerance
)

 Checks if two floating point numbers are nearly equal. Math/UnrealMathUtility.h  

static bool IsNearlyEqual ( Arg1 X,
Arg2 Y
)

   Math/UnrealMathUtility.h  

static bool IsNearlyEqual ( double A,
double B,
double ErrorTolerance
)

   Math/UnrealMathUtility.h  

static bool IsNearlyEqualByULP ( float A,
float B,
int32 MaxUlps
)

 Check if two floating point numbers are nearly equal to within specific number of units of last place (ULP). Math/UnrealMathUtility.h  

static bool IsNearlyEqualByULP ( double A,
double B,
int32 MaxUlps
)

 Check if two floating point numbers are nearly equal to within specific number of units of last place (ULP). Math/UnrealMathUtility.h  

static bool IsNearlyZero ( float Value,
float ErrorTolerance
)

 Checks if a floating point number is nearly zero. Math/UnrealMathUtility.h  

static bool IsNearlyZero ( Arg1 X,
Arg2 Y
)

   Math/UnrealMathUtility.h  

static bool IsNearlyZero ( double Value,
double ErrorTolerance
)

 Checks if a floating point number is nearly zero. Math/UnrealMathUtility.h  

static bool IsPowerOfTwo ( T Value
)

 Checks whether a number is a power of two. Math/UnrealMathUtility.h  

static bool IsWithin ( const T& TestValue,
const U& MinValue,
const U& MaxValue
)

 Checks if value is within a range, exclusive on MaxValue) Math/UnrealMathUtility.h  

static bool IsWithinInclusive ( const T& TestValue,
const U& MinValue,
const U& MaxValue
)

 Checks if value is within a range, inclusive on MaxValue) Math/UnrealMathUtility.h  

static int32 LeastCommonMultiplier ( int32 a,
int32 b
)

 LCM = a/gcd * b a and b are the number we want to find the lcm Math/UnrealMathUtility.h  

static T Lerp ( const T& A,
const T& B,
const U& Alpha
)

 Performs a linear interpolation between two values, Alpha ranges from 0-1 Math/UnrealMathUtility.h  

static decltype(A *B) Lerp ( const T1& A,
const T2& B,
const T3& Alpha
)

 Allow passing of differing A/B types. Math/UnrealMathUtility.h  

static T Lerp ( const T& A,
const T& B,
const U& Alpha
)

 Custom lerps defined for those classes not suited to the default implemenation. Math/UnrealMathUtility.h  

static UE::Math::TRotator< T > LerpRange ( const UE::Math::TRotator< T >& A,
const UE::Math::TRotator< T >& B,
U Alpha
)

 Rotator specific interpolation Similar to Lerp, but does not take the shortest path. Math/UnrealMathUtility.h  

static decltype(A *B) LerpStable ( const T1& A,
const T2& B,
const T3& Alpha
)

 Allow passing of differing A/B types. Math/UnrealMathUtility.h  

static T LerpStable ( const T& A,
const T& B,
double Alpha
)

 Performs a linear interpolation between two values, Alpha ranges from 0-1. Math/UnrealMathUtility.h  

static T LerpStable ( const T& A,
const T& B,
float Alpha
)

 Performs a linear interpolation between two values, Alpha ranges from 0-1. Math/UnrealMathUtility.h  

static bool LineBoxIntersection ( const UE::Math::TBox< FReal >& Box,
const UE::Math::TVector< FReal >& Start,
const UE::Math::TVector< FReal >& End,
const UE::Math::TVector< FReal >& Direction
)

 Determines whether a line intersects a box. Math/UnrealMathUtility.h  

static bool LineBoxIntersection ( const UE::Math::TBox< FReal >& Box,
const UE::Math::TVector< FReal >& Start,
const UE::Math::TVector< FReal >& End,
const UE::Math::TVector< FReal >& Direction,
const UE::Math::TVector< FReal >& OneOverDirection
)

 Determines whether a line intersects a box. Math/UnrealMathUtility.h  

static bool LineBoxIntersection2D ( const UE::Math::TBox2< FReal >& Box,
const UE::Math::TVector2< FReal >& Start,
const UE::Math::TVector2< FReal >& End
)

 Determines whether a line intersects a 2D box.FMath inline functions Math/UnrealMathUtility.h  

static bool LineExtentBoxIntersection ( const FBox& inBox,
const FVector& Start,
const FVector& End,
const FVector& Extent,
FVector& HitLocation,
FVector& HitNormal,
float& HitTime
)

 Swept-Box vs Box test Math/UnrealMathUtility.h  

static UE::Math::TVector< FReal > LinePlaneIntersection ( const UE::Math::TVector< FReal >& Point1,
const UE::Math::TVector< FReal >& Point2,
const UE::Math::TPlane< FReal >& Plane
)

 Find the intersection of a line and a plane. Math/UnrealMathUtility.h  

static UE::Math::TVector< FReal > LinePlaneIntersection ( const UE::Math::TVector< FReal >& Point1,
const UE::Math::TVector< FReal >& Point2,
const UE::Math::TVector< FReal >& PlaneOrigin,
const UE::Math::TVector< FReal >& PlaneNormal
)

 Find the intersection of a line and an offset plane. Math/UnrealMathUtility.h  

static bool LineSphereIntersection ( const UE::Math::TVector< FReal >& Start,
const UE::Math::TVector< FReal >& Dir,
FReal Length,
const UE::Math::TVector< FReal >& Origin,
FReal Radius
)

 Determines whether a line intersects a sphere. Math/UnrealMathUtility.h  

static float Log2 ( float Value
)

 Computes the base 2 logarithm of the specified value Math/UnrealMathUtility.h  

static double Log2 ( double Value
)

 Computes the base 2 logarithm of the specified value Math/UnrealMathUtility.h  

static float MakePulsatingValue ( const double InCurrentTime,
const float InPulsesPerSecond,
const float InPhase
)

 Simple function to create a pulsating scalar value Math/UnrealMathUtility.h  

static bool MatrixInverse ( FMatrix44f* DstMatrix,
const FMatrix44f* SrcMatrix
)

 Calculate the inverse of an FMatrix44. Math/UnrealMathUtility.h  

static bool MatrixInverse ( FMatrix44d* DstMatrix,
const FMatrix44d* SrcMatrix
)

 Calculate the inverse of an FMatrix44.Src == Dst is allowed Math/UnrealMathUtility.h  

static T Max3 ( const T A,
const T B,
const T C
)

 Returns highest of 3 values Math/UnrealMathUtility.h  

static int32 Max3Index ( const T A,
const T B,
const T C
)

   Math/UnrealMathUtility.h  

static bool MemoryTest ( void* BaseAddress,
uint32 NumBytes
)

 Tests a memory region to see that it's working properly. Math/UnrealMathUtility.h  

static T Min3 ( const T A,
const T B,
const T C
)

 Returns lowest of 3 values Math/UnrealMathUtility.h  

static int32 Min3Index ( const T A,
const T B,
const T C
)

 Returns index of the lowest value Math/UnrealMathUtility.h  

static auto Modulo ( ValueType Value,
BaseType Base
)

   Math/UnrealMathUtility.h  

static float PerlinNoise1D ( float Value
)

 Generates a 1D Perlin noise from the given value. Math/UnrealMathUtility.h  

static float PerlinNoise2D ( const FVector2D& Location
)

 Generates a 2D Perlin noise sample at the given location. Math/UnrealMathUtility.h  

static float PerlinNoise3D ( const FVector& Location
)

 Generates a 3D Perlin noise sample at the given location. Math/UnrealMathUtility.h  

static bool PlaneAABBIntersection ( const FPlane& P,
const FBox& AABB
)

 Determine if a plane and an AABB intersect Math/UnrealMathUtility.h  

static int32 PlaneAABBRelativePosition ( const FPlane& P,
const FBox& AABB
)

 Determine the position of an AABB relative to a plane: completely above (in the direction of the normal of the plane), completely below or intersects it Math/UnrealMathUtility.h  

static bool PointBoxIntersection ( const UE::Math::TVector< FReal >& Point,
const UE::Math::TBox< FReal >& Box
)

 Determines whether a point is inside a box.FMath inline functions Math/UnrealMathUtility.h  

static float PointDistToLine ( const FVector& Point,
const FVector& Direction,
const FVector& Origin
)

   Math/UnrealMathUtility.h  

static float PointDistToLine ( const FVector& Point,
const FVector& Direction,
const FVector& Origin,
FVector& OutClosestPoint
)

 Calculates the distance of a given Point in world space to a given line, defined by the vector couple (Origin, Direction). Math/UnrealMathUtility.h  

static float PointDistToSegment ( const FVector& Point,
const FVector& StartPoint,
const FVector& EndPoint
)

 Returns distance from a point to the closest point on a segment. Math/UnrealMathUtility.h  

static float PointDistToSegmentSquared ( const FVector& Point,
const FVector& StartPoint,
const FVector& EndPoint
)

 Returns square of the distance from a point to the closest point on a segment. Math/UnrealMathUtility.h  

static bool PointsAreCoplanar ( const TArray< FVector >& Points,
const float Tolerance
)

 Determines whether a given set of points are coplanar, with a tolerance. Math/UnrealMathUtility.h  

static void PolarToCartesian ( const T Rad,
const T Ang,
T& OutX,
T& OutY
)

 Converts given Polar coordinate pair to Cartesian coordinate system. Math/UnrealMathUtility.h  

static void PolarToCartesian ( const UE::Math::TVector2< T > InPolar,
UE::Math::TVector2< T >& OutCart
)

 Converts given Polar coordinate pair to Cartesian coordinate system. Math/UnrealMathUtility.h  

static UE::Math::TQuat< T > QInterpConstantTo ( const UE::Math::TQuat< T >& Current,
const UE::Math::TQuat< T >& Target,
float DeltaTime,
float InterpSpeed
)

 Interpolate quaternion from Current to Target with constant step (in radians) Math/UnrealMathUtility.h  

static UE::Math::TQuat< T > QInterpTo ( const UE::Math::TQuat< T >& Current,
const UE::Math::TQuat< T >& Target,
float DeltaTime,
float InterpSpeed
)

 Interpolate quaternion from Current to Target. Math/UnrealMathUtility.h  

static uint8 Quantize8SignedByte ( float x
)

   Math/UnrealMathUtility.h  

static uint8 Quantize8UnsignedByte ( float x
)

   Math/UnrealMathUtility.h  

static decltype(RadVal *(180.f/(3.1415926535897932f))) RadiansToDegrees ( T const& RadVal
)

 Converts radians to degrees. Math/UnrealMathUtility.h  

static double RadiansToDegrees ( double const& RadVal
)

   Math/UnrealMathUtility.h  

static float RadiansToDegrees ( float const& RadVal
)

   Math/UnrealMathUtility.h  

static bool RandBool()

 Util to generate a random boolean. Math/UnrealMathUtility.h  

static int32 RandHelper ( int32 A
)

 Helper function for rand implementations. Returns a random number in [0..A) Math/UnrealMathUtility.h  

static int64 RandHelper64 ( int64 A
)

   Math/UnrealMathUtility.h  

static FVector RandPointInBox ( const FBox& Box
)

 Returns a random point within the passed in bounding box Math/UnrealMathUtility.h  

static FVector2D RandPointInCircle ( float CircleRadius
)

 Returns a random point, uniformly distributed, within the specified radius Math/UnrealMathUtility.h  

static int32 RandRange ( int32 Min,
int32 Max
)

 Helper function for rand implementations. Returns a random number >= Min and <= Max Math/UnrealMathUtility.h  

static int64 RandRange ( int64 Min,
int64 Max
)

   Math/UnrealMathUtility.h  

static float RandRange ( float InMin,
float InMax
)

 Util to generate a random number in a range. Math/UnrealMathUtility.h  

static double RandRange ( double InMin,
double InMax
)

   Math/UnrealMathUtility.h  

static UE::Math::TVector< FReal > RayPlaneIntersection ( const UE::Math::TVector< FReal >& RayOrigin,
const UE::Math::TVector< FReal >& RayDirection,
const UE::Math::TPlane< FReal >& Plane
)

 Find the intersection of a ray and a plane. Math/UnrealMathUtility.h  

static FReal RayPlaneIntersectionParam ( const UE::Math::TVector< FReal >& RayOrigin,
const UE::Math::TVector< FReal >& RayDirection,
const UE::Math::TPlane< FReal >& Plane
)

 Find the intersection of a ray and a plane. Math/UnrealMathUtility.h  

static FRotator RInterpConstantTo ( const FRotator& Current,
const FRotator& Target,
float DeltaTime,
float InterpSpeed
)

 Interpolate rotator from Current to Target with constant step Math/UnrealMathUtility.h  

static FRotator RInterpTo ( const FRotator& Current,
const FRotator& Target,
float DeltaTime,
float InterpSpeed
)

 Interpolate rotator from Current to Target. Math/UnrealMathUtility.h  

static double RoundFromZero ( double F
)

   Math/UnrealMathUtility.h  

static float RoundFromZero ( float F
)

 Converts a floating point number to an integer which is further from zero, "larger" in absolute value: 0.1 becomes 1, -0.1 becomes -1 Math/UnrealMathUtility.h  

static float RoundHalfFromZero ( float F
)

 Converts a floating point number to the nearest integer, equidistant ties go to the value which is further from zero: -0.5 becomes -1.0, 0.5 becomes 1.0 Math/UnrealMathUtility.h  

static double RoundHalfFromZero ( double F
)

   Math/UnrealMathUtility.h  

static float RoundHalfToEven ( float F
)

 Converts a floating point number to the nearest integer, equidistant ties go to the value which is closest to an even value: 1.5 becomes 2, 0.5 becomes 0 Math/UnrealMathUtility.h  

static double RoundHalfToEven ( double F
)

   Math/UnrealMathUtility.h  

static double RoundHalfToZero ( double F
)

   Math/UnrealMathUtility.h  

static float RoundHalfToZero ( float F
)

 Converts a floating point number to the nearest integer, equidistant ties go to the value which is closer to zero: -0.5 becomes 0, 0.5 becomes 0 Math/UnrealMathUtility.h  

static float RoundToNegativeInfinity ( float F
)

 Converts a floating point number to an integer which is more negative: 0.1 becomes 0, -0.1 becomes -1 Math/UnrealMathUtility.h  

static double RoundToNegativeInfinity ( double F
)

   Math/UnrealMathUtility.h  

static float RoundToPositiveInfinity ( float F
)

 Converts a floating point number to an integer which is more positive: 0.1 becomes 1, -0.1 becomes 0 Math/UnrealMathUtility.h  

static double RoundToPositiveInfinity ( double F
)

   Math/UnrealMathUtility.h  

static float RoundToZero ( float F
)

 Converts a floating point number to an integer which is closer to zero, "smaller" in absolute value: 0.1 becomes 0, -0.1 becomes 0 Math/UnrealMathUtility.h  

static double RoundToZero ( double F
)

   Math/UnrealMathUtility.h  

static void SegmentDistToSegment ( FVector A1,
FVector B1,
FVector A2,
FVector B2,
FVector& OutP1,
FVector& OutP2
)

 Find closest points between 2 segments. Math/UnrealMathUtility.h  

static void SegmentDistToSegmentSafe ( UE::Math::TVector< T > A1,
UE::Math::TVector< T > B1,
UE::Math::TVector< T > A2,
UE::Math::TVector< T > B2,
UE::Math::TVector< T >& OutP1,
UE::Math::TVector< T >& OutP2
)

 Find closest points between 2 segments. Math/UnrealMathUtility.h  

static bool SegmentIntersection2D ( const FVector& SegmentStartA,
const FVector& SegmentEndA,
const FVector& SegmentStartB,
const FVector& SegmentEndB,
FVector& out_IntersectionPoint
)

 Returns true if there is an intersection between the segment specified by SegmentStartA and SegmentEndA, and the segment specified by SegmentStartB and SegmentEndB, in 2D space. Math/UnrealMathUtility.h  

static bool SegmentPlaneIntersection ( const FVector& StartPoint,
const FVector& EndPoint,
const FPlane& Plane,
FVector& out_IntersectionPoint
)

 Returns true if there is an intersection between the segment specified by StartPoint and Endpoint, and the plane on which polygon Plane lies. Math/UnrealMathUtility.h  

static bool SegmentTriangleIntersection ( const FVector& StartPoint,
const FVector& EndPoint,
const FVector& A,
const FVector& B,
const FVector& C,
FVector& OutIntersectPoint,
FVector& OutTriangleNormal
)

 Returns true if there is an intersection between the segment specified by StartPoint and Endpoint, and the Triangle defined by A, B and C. Math/UnrealMathUtility.h  

static void SetBoolInBitField ( uint8* Ptr,
uint32 Index,
bool bSet
)

 Set a bit in memory created from bitflags (uint32 Value:1), used for EngineShowFlags, TestBitFieldFunctions() tests the implementation Math/UnrealMathUtility.h  

static void SinCos ( std::decay_t< T >* ScalarSin,
std::decay_t< T >* ScalarCos,
T Value
)

 Computes the sine and cosine of a scalar value. Math/UnrealMathUtility.h  

static void SinCos ( double* ScalarSin,
double* ScalarCos,
double Value
)

   Math/UnrealMathUtility.h  

static void SinCos ( T* ScalarSin,
T* ScalarCos,
U Value
)

   Math/UnrealMathUtility.h  

static T SmoothStep ( T A,
T B,
T X
)

 Returns a smooth Hermite interpolation between 0 and 1 for the value X (where X ranges between A and B) Clamped to 0 for X <= A and 1 for X >= B. Math/UnrealMathUtility.h  

static bool SphereAABBIntersection ( const UE::Math::TSphere< FReal >& Sphere,
const UE::Math::TBox< FReal >& AABB
)

 Converts a sphere into a point plus radius squared for the test above Math/UnrealMathUtility.h  

static bool SphereAABBIntersection ( const UE::Math::TVector< FReal >& SphereCenter,
const FReal RadiusSquared,
const UE::Math::TBox< FReal >& AABB
)

 Performs a sphere vs box intersection test using Arvo's algorithm: Math/UnrealMathUtility.h  

static bool SphereConeIntersection ( const FVector& SphereCenter,
float SphereRadius,
const FVector& ConeAxis,
float ConeAngleSin,
float ConeAngleCos
)

 Assumes the cone tip is at 0,0,0 (means the SphereCenter is relative to the cone tip) Math/UnrealMathUtility.h  

static void SphereDistToLine ( FVector SphereOrigin,
float SphereRadius,
FVector LineOrigin,
FVector LineDir,
FVector& OutClosestPoint
)

 Find closest point on a Sphere to a Line. Math/UnrealMathUtility.h  

static void SpringDamper ( T& InOutValue,
T& InOutValueRate,
const T& InTargetValue,
const T& InTargetValueRate,
const float InDeltaTime,
const float InUndampedFrequency,
const float InDampingRatio
)

 Smooths a value using a spring damper towards a target. Math/UnrealMathUtility.h  

static void SpringDamperSmoothing ( T& InOutValue,
T& InOutValueRate,
const T& InTargetValue,
const T& InTargetValueRate,
const float InDeltaTime,
const float InSmoothingTime,
const float InDampingRatio
)

 Smooths a value using a spring damper towards a target. Math/UnrealMathUtility.h  

static T Square ( const T A
)

 Multiples value by itself Math/UnrealMathUtility.h  

static bool TIsNearlyEqualByULP ( FloatType A,
FloatType B,
int32 MaxUlps
)

   Math/UnrealMathUtility.h  

static float TruncateToHalfIfClose ( float F,
float Tolerance
)

 Truncates a floating point number to half if closer than the given tolerance. Math/UnrealMathUtility.h  

static double TruncateToHalfIfClose ( double F,
double Tolerance
)

   Math/UnrealMathUtility.h  

static T UnwindDegrees ( T A
)

 Utility to ensure angle is between +/- 180 degrees by unwinding. Math/UnrealMathUtility.h  

static T UnwindRadians ( T A
)

 Given a heading which may be outside the +/- PI range, 'unwind' it back into that range. Math/UnrealMathUtility.h  

static FVector2D Vector2DInterpConstantTo ( const FVector2D& Current,
const FVector2D& Target,
float DeltaTime,
float InterpSpeed
)

 Interpolate vector2D from Current to Target with constant step Math/UnrealMathUtility.h  

static UE::Math::TVector2< T > Vector2DInterpTo ( const UE::Math::TVector2< T >& Current,
const UE::Math::TVector2< T >& Target,
float DeltaTime,
float InterpSpeed
)

 Interpolate vector2D from Current to Target. Math/UnrealMathUtility.h  

static FVector VInterpConstantTo ( const FVector& Current,
const FVector& Target,
float DeltaTime,
float InterpSpeed
)

 Interpolate vector from Current to Target with constant step Math/UnrealMathUtility.h  

static FVector VInterpNormalRotationTo ( const FVector& Current,
const FVector& Target,
float DeltaTime,
float RotationSpeedDegrees
)

 Interpolate a normal vector Current to Target, by interpolating the angle between those vectors with constant step. Math/UnrealMathUtility.h  

static FVector VInterpTo ( const FVector& Current,
const FVector& Target,
float DeltaTime,
float InterpSpeed
)

 Interpolate vector from Current to Target. Math/UnrealMathUtility.h  

static FVector VRand()

 Return a uniformly distributed random unit length vector = point on the unit sphere surface. Math/UnrealMathUtility.h  

static FVector VRandCone ( FVector const& Dir,
float ConeHalfAngleRad
)

 Returns a random unit vector, uniformly distributed, within the specified cone ConeHalfAngleRad is the half-angle of cone, in radians. Math/UnrealMathUtility.h  

static FVector VRandCone ( FVector const& Dir,
float HorizontalConeHalfAngleRad,
float VerticalConeHalfAngleRad
)

 This is a version of VRandCone that handles "squished" cones, i.e. with different angle limits in the Y and Z axes. Math/UnrealMathUtility.h  

static T WeightedMovingAverage ( T CurrentSample,
T PreviousSample,
T Weight
)

 Calculates the new value in a weighted moving average series using the previous value and the weight Math/UnrealMathUtility.h  

static void WindRelativeAnglesDegrees ( float InAngle0,
float& InOutAngle1
)

 Given two angles in degrees, 'wind' the rotation in Angle1 so that it avoids >180 degree flips. Math/UnrealMathUtility.h  

static void WindRelativeAnglesDegrees ( double InAngle0,
double& InOutAngle1
)

   Math/UnrealMathUtility.h  

static T Wrap ( const T X,
const T Min,
const T Max
)

 Wraps X to be between Min and Max, inclusive. Math/UnrealMathUtility.h  

static T WrapExclusive ( const T X,
const T Min,
const T Max
)

 Wraps X to be between Min and Max, exclusive. Will never return Max. Math/UnrealMathUtility.h  

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