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Ogre::Math Class Reference

Class to provide access to common mathematical functions. More...

#include <OgreMath.h>

List of all members.

Public Types

enum  AngleUnit { AU_DEGREE, AU_RADIAN }
 The angular units used by the API. More...

Public Member Functions

 Math (unsigned int trigTableSize=4096)
 Default constructor.
 ~Math ()
 Default destructor.

Static Public Member Functions

static int IAbs (int iValue)
static int ICeil (float fValue)
static int IFloor (float fValue)
static int ISign (int iValue)
static Real Abs (Real fValue)
static Degree Abs (const Degree &dValue)
static Radian Abs (const Radian &rValue)
static Radian ACos (Real fValue)
static Radian ASin (Real fValue)
static Radian ATan (Real fValue)
static Radian ATan2 (Real fY, Real fX)
static Real Ceil (Real fValue)
static Real Cos (const Radian &fValue, bool useTables=false)
 Cosine function.
static Real Cos (Real fValue, bool useTables=false)
 Cosine function.
static Real Exp (Real fValue)
static Real Floor (Real fValue)
static Real Log (Real fValue)
static Real Pow (Real fBase, Real fExponent)
static Real Sign (Real fValue)
static Radian Sign (const Radian &rValue)
static Degree Sign (const Degree &dValue)
static Real Sin (const Radian &fValue, bool useTables=false)
 Sine function.
static Real Sin (Real fValue, bool useTables=false)
 Sine function.
static Real Sqr (Real fValue)
static Real Sqrt (Real fValue)
static Radian Sqrt (const Radian &fValue)
static Degree Sqrt (const Degree &fValue)
static Real InvSqrt (Real fValue)
 Inverse square root i.e.
static Real UnitRandom ()
static Real RangeRandom (Real fLow, Real fHigh)
static Real SymmetricRandom ()
static Real Tan (const Radian &fValue, bool useTables=false)
 Tangent function.
static Real Tan (Real fValue, bool useTables=false)
 Tangent function.
static Real DegreesToRadians (Real degrees)
static Real RadiansToDegrees (Real radians)
static void setAngleUnit (AngleUnit unit)
 These functions used to set the assumed angle units (radians or degrees) expected when using the Angle type.
static AngleUnit getAngleUnit (void)
 Get the unit being used for angles.
static Real AngleUnitsToRadians (Real units)
 Convert from the current AngleUnit to radians.
static Real RadiansToAngleUnits (Real radians)
 Convert from radians to the current AngleUnit .
static Real AngleUnitsToDegrees (Real units)
 Convert from the current AngleUnit to degrees.
static Real DegreesToAngleUnits (Real degrees)
 Convert from degrees to the current AngleUnit.
static bool pointInTri2D (const Vector2 &p, const Vector2 &a, const Vector2 &b, const Vector2 &c)
 Checks whether a given point is inside a triangle, in a 2-dimensional (Cartesian) space.
static bool pointInTri3D (const Vector3 &p, const Vector3 &a, const Vector3 &b, const Vector3 &c, const Vector3 &normal)
 Checks whether a given 3D point is inside a triangle.
static std::pair< bool, Realintersects (const Ray &ray, const Plane &plane)
 Ray / plane intersection, returns boolean result and distance.
static std::pair< bool, Realintersects (const Ray &ray, const Sphere &sphere, bool discardInside=true)
 Ray / sphere intersection, returns boolean result and distance.
static std::pair< bool, Realintersects (const Ray &ray, const AxisAlignedBox &box)
 Ray / box intersection, returns boolean result and distance.
static bool intersects (const Ray &ray, const AxisAlignedBox &box, Real *d1, Real *d2)
 Ray / box intersection, returns boolean result and two intersection distance.
static std::pair< bool, Realintersects (const Ray &ray, const Vector3 &a, const Vector3 &b, const Vector3 &c, const Vector3 &normal, bool positiveSide=true, bool negativeSide=true)
 Ray / triangle intersection, returns boolean result and distance.
static std::pair< bool, Realintersects (const Ray &ray, const Vector3 &a, const Vector3 &b, const Vector3 &c, bool positiveSide=true, bool negativeSide=true)
 Ray / triangle intersection, returns boolean result and distance.
static bool intersects (const Sphere &sphere, const AxisAlignedBox &box)
 Sphere / box intersection test.
static bool intersects (const Plane &plane, const AxisAlignedBox &box)
 Plane / box intersection test.
static std::pair< bool, Realintersects (const Ray &ray, const std::vector< Plane > &planeList, bool normalIsOutside)
 Ray / convex plane list intersection test.
static std::pair< bool, Realintersects (const Ray &ray, const std::list< Plane > &planeList, bool normalIsOutside)
 Ray / convex plane list intersection test.
static bool intersects (const Sphere &sphere, const Plane &plane)
 Sphere / plane intersection test.
static bool RealEqual (Real a, Real b, Real tolerance=std::numeric_limits< Real >::epsilon())
 Compare 2 reals, using tolerance for inaccuracies.
static Vector3 calculateTangentSpaceVector (const Vector3 &position1, const Vector3 &position2, const Vector3 &position3, Real u1, Real v1, Real u2, Real v2, Real u3, Real v3)
 Calculates the tangent space vector for a given set of positions / texture coords.
static Matrix4 buildReflectionMatrix (const Plane &p)
 Build a reflection matrix for the passed in plane.
static Vector4 calculateFaceNormal (const Vector3 &v1, const Vector3 &v2, const Vector3 &v3)
 Calculate a face normal, including the w component which is the offset from the origin.
static Vector3 calculateBasicFaceNormal (const Vector3 &v1, const Vector3 &v2, const Vector3 &v3)
 Calculate a face normal, no w-information.
static Vector4 calculateFaceNormalWithoutNormalize (const Vector3 &v1, const Vector3 &v2, const Vector3 &v3)
 Calculate a face normal without normalize, including the w component which is the offset from the origin.
static Vector3 calculateBasicFaceNormalWithoutNormalize (const Vector3 &v1, const Vector3 &v2, const Vector3 &v3)
 Calculate a face normal without normalize, no w-information.
static Real gaussianDistribution (Real x, Real offset=0.0f, Real scale=1.0f)
 Generates a value based on the gaussian (normal) distribution function with the given offset and scale parameters.

Static Public Attributes

static const Real POS_INFINITY
static const Real NEG_INFINITY
static const Real PI
static const Real TWO_PI
static const Real HALF_PI
static const Real fDeg2Rad
static const Real fRad2Deg

Protected Member Functions

void buildTrigTables ()
 Private function to build trig tables.

Static Protected Member Functions

static Real SinTable (Real fValue)
static Real TanTable (Real fValue)

Static Protected Attributes

static AngleUnit msAngleUnit
static int mTrigTableSize
 Size of the trig tables as determined by constructor.
static Real mTrigTableFactor
 Radian -> index factor value ( mTrigTableSize / 2 * PI ).
static RealmSinTable
static RealmTanTable


Detailed Description

Class to provide access to common mathematical functions.

Remarks:
Most of the maths functions are aliased versions of the C runtime library functions. They are aliased here to provide future optimisation opportunities, either from faster RTLs or custom math approximations.
Note:

This is based on MgcMath.h from Wild Magic.

Definition at line 165 of file OgreMath.h.


Member Enumeration Documentation

enum Ogre::Math::AngleUnit
 

The angular units used by the API.

This functionality is now deprecated in favor of discreet angular unit types ( see Degree and Radian above ). The only place this functionality is actually still used is when parsing files. Search for usage of the Angle class for those instances

Enumeration values:
AU_DEGREE 
AU_RADIAN 

Definition at line 173 of file OgreMath.h.


Constructor & Destructor Documentation

Ogre::Math::Math unsigned int  trigTableSize = 4096  ) 
 

Default constructor.

Parameters:
trigTableSize Optional parameter to set the size of the tables used to implement Sin, Cos, Tan

Ogre::Math::~Math  ) 
 

Default destructor.


Member Function Documentation

static Radian Ogre::Math::Abs const Radian rValue  )  [static]
 

Definition at line 216 of file OgreMath.h.

References Ogre::Radian::valueRadians().

static Degree Ogre::Math::Abs const Degree dValue  )  [static]
 

Definition at line 215 of file OgreMath.h.

References Ogre::Degree::valueDegrees().

static Real Ogre::Math::Abs Real  fValue  )  [static]
 

Definition at line 214 of file OgreMath.h.

Referenced by Ogre::Vector3::directionEquals().

static Radian Ogre::Math::ACos Real  fValue  )  [static]
 

Referenced by Ogre::Vector3::directionEquals().

static Real Ogre::Math::AngleUnitsToDegrees Real  units  )  [static]
 

Convert from the current AngleUnit to degrees.

Referenced by Ogre::Angle::operator Degree().

static Real Ogre::Math::AngleUnitsToRadians Real  units  )  [static]
 

Convert from the current AngleUnit to radians.

Referenced by Ogre::Angle::operator Radian().

static Radian Ogre::Math::ASin Real  fValue  )  [static]
 

static Radian Ogre::Math::ATan Real  fValue  )  [static]
 

Definition at line 219 of file OgreMath.h.

static Radian Ogre::Math::ATan2 Real  fY,
Real  fX
[static]
 

Definition at line 220 of file OgreMath.h.

static Matrix4 Ogre::Math::buildReflectionMatrix const Plane p  )  [static]
 

Build a reflection matrix for the passed in plane.

void Ogre::Math::buildTrigTables  )  [protected]
 

Private function to build trig tables.

static Vector3 Ogre::Math::calculateBasicFaceNormal const Vector3 v1,
const Vector3 v2,
const Vector3 v3
[static]
 

Calculate a face normal, no w-information.

static Vector3 Ogre::Math::calculateBasicFaceNormalWithoutNormalize const Vector3 v1,
const Vector3 v2,
const Vector3 v3
[static]
 

Calculate a face normal without normalize, no w-information.

static Vector4 Ogre::Math::calculateFaceNormal const Vector3 v1,
const Vector3 v2,
const Vector3 v3
[static]
 

Calculate a face normal, including the w component which is the offset from the origin.

static Vector4 Ogre::Math::calculateFaceNormalWithoutNormalize const Vector3 v1,
const Vector3 v2,
const Vector3 v3
[static]
 

Calculate a face normal without normalize, including the w component which is the offset from the origin.

static Vector3 Ogre::Math::calculateTangentSpaceVector const Vector3 position1,
const Vector3 position2,
const Vector3 position3,
Real  u1,
Real  v1,
Real  u2,
Real  v2,
Real  u3,
Real  v3
[static]
 

Calculates the tangent space vector for a given set of positions / texture coords.

static Real Ogre::Math::Ceil Real  fValue  )  [static]
 

Definition at line 221 of file OgreMath.h.

static Real Ogre::Math::Cos Real  fValue,
bool  useTables = false
[static]
 

Cosine function.

Parameters:
fValue Angle in radians
useTables If true, uses lookup tables rather than calculation - faster but less accurate.

Definition at line 240 of file OgreMath.h.

static Real Ogre::Math::Cos const Radian fValue,
bool  useTables = false
[static]
 

Cosine function.

Parameters:
fValue Angle in radians
useTables If true, uses lookup tables rather than calculation - faster but less accurate.

Definition at line 230 of file OgreMath.h.

References Ogre::Radian::valueRadians().

static Real Ogre::Math::DegreesToAngleUnits Real  degrees  )  [static]
 

Convert from degrees to the current AngleUnit.

Referenced by Ogre::Degree::valueAngleUnits().

static Real Ogre::Math::DegreesToRadians Real  degrees  )  [static]
 

Definition at line 323 of file OgreMath.h.

Referenced by Ogre::Degree::valueRadians().

static Real Ogre::Math::Exp Real  fValue  )  [static]
 

Definition at line 244 of file OgreMath.h.

static Real Ogre::Math::Floor Real  fValue  )  [static]
 

Definition at line 246 of file OgreMath.h.

static Real Ogre::Math::gaussianDistribution Real  x,
Real  offset = 0.0f,
Real  scale = 1.0f
[static]
 

Generates a value based on the gaussian (normal) distribution function with the given offset and scale parameters.

static AngleUnit Ogre::Math::getAngleUnit void   )  [static]
 

Get the unit being used for angles.

static int Ogre::Math::IAbs int  iValue  )  [static]
 

Definition at line 209 of file OgreMath.h.

static int Ogre::Math::ICeil float  fValue  )  [static]
 

Definition at line 210 of file OgreMath.h.

static int Ogre::Math::IFloor float  fValue  )  [static]
 

Definition at line 211 of file OgreMath.h.

static bool Ogre::Math::intersects const Sphere sphere,
const Plane plane
[static]
 

Sphere / plane intersection test.

Remarks:
NB just do a plane.getDistance(sphere.getCenter()) for more detail!

static std::pair<bool, Real> Ogre::Math::intersects const Ray ray,
const std::list< Plane > &  planeList,
bool  normalIsOutside
[static]
 

Ray / convex plane list intersection test.

Parameters:
ray The ray to test with
plaeList List of planes which form a convex volume
normalIsOutside Does the normal point outside the volume

static std::pair<bool, Real> Ogre::Math::intersects const Ray ray,
const std::vector< Plane > &  planeList,
bool  normalIsOutside
[static]
 

Ray / convex plane list intersection test.

Parameters:
ray The ray to test with
plaeList List of planes which form a convex volume
normalIsOutside Does the normal point outside the volume

static bool Ogre::Math::intersects const Plane plane,
const AxisAlignedBox box
[static]
 

Plane / box intersection test.

static bool Ogre::Math::intersects const Sphere sphere,
const AxisAlignedBox box
[static]
 

Sphere / box intersection test.

static std::pair<bool, Real> Ogre::Math::intersects const Ray ray,
const Vector3 a,
const Vector3 b,
const Vector3 c,
bool  positiveSide = true,
bool  negativeSide = true
[static]
 

Ray / triangle intersection, returns boolean result and distance.

Parameters:
ray The ray.
a The triangle's first vertex.
b The triangle's second vertex.
c The triangle's third vertex.
positiveSide Intersect with "positive side" of the triangle
negativeSide Intersect with "negative side" of the triangle
Returns:
If the ray is intersects the triangle, a pair of true and the distance between intersection point and ray origin returned.
If the ray isn't intersects the triangle, a pair of false and 0 returned.

static std::pair<bool, Real> Ogre::Math::intersects const Ray ray,
const Vector3 a,
const Vector3 b,
const Vector3 c,
const Vector3 normal,
bool  positiveSide = true,
bool  negativeSide = true
[static]
 

Ray / triangle intersection, returns boolean result and distance.

Parameters:
ray The ray.
a The triangle's first vertex.
b The triangle's second vertex.
c The triangle's third vertex.
normal The triangle plane's normal (passed in rather than calculated on demand since the callermay already have it), doesn't need normalised since we don't care.
positiveSide Intersect with "positive side" of the triangle
negativeSide Intersect with "negative side" of the triangle
Returns:
If the ray is intersects the triangle, a pair of true and the distance between intersection point and ray origin returned.
If the ray isn't intersects the triangle, a pair of false and 0 returned.

static bool Ogre::Math::intersects const Ray ray,
const AxisAlignedBox box,
Real d1,
Real d2
[static]
 

Ray / box intersection, returns boolean result and two intersection distance.

Parameters:
ray The ray.
box The box.
d1 A real pointer to retrieve the near intersection distance from the ray origin, maybe null which means don't care about the near intersection distance.
d2 A real pointer to retrieve the far intersection distance from the ray origin, maybe null which means don't care about the far intersection distance.
Returns:
If the ray is intersects the box, true is returned, and the near intersection distance is return by d1, the far intersection distance is return by d2. Guarantee 0 <= d1 <= d2.
If the ray isn't intersects the box, false is returned, and d1 and d2 is unmodified.

static std::pair<bool, Real> Ogre::Math::intersects const Ray ray,
const AxisAlignedBox box
[static]
 

Ray / box intersection, returns boolean result and distance.

static std::pair<bool, Real> Ogre::Math::intersects const Ray ray,
const Sphere sphere,
bool  discardInside = true
[static]
 

Ray / sphere intersection, returns boolean result and distance.

static std::pair<bool, Real> Ogre::Math::intersects const Ray ray,
const Plane plane
[static]
 

Ray / plane intersection, returns boolean result and distance.

Referenced by Ogre::Sphere::intersects(), Ogre::Ray::intersects(), Ogre::PlaneBoundedVolume::intersects(), and Ogre::AxisAlignedBox::intersects().

static Real Ogre::Math::InvSqrt Real  fValue  )  [static]
 

Inverse square root i.e.

1 / Sqrt(x), good for vector normalisation.

static int Ogre::Math::ISign int  iValue  )  [static]
 

static Real Ogre::Math::Log Real  fValue  )  [static]
 

Definition at line 248 of file OgreMath.h.

static bool Ogre::Math::pointInTri2D const Vector2 p,
const Vector2 a,
const Vector2 b,
const Vector2 c
[static]
 

Checks whether a given point is inside a triangle, in a 2-dimensional (Cartesian) space.

Remarks:
The vertices of the triangle must be given in either trigonometrical (anticlockwise) or inverse trigonometrical (clockwise) order.
Parameters:
p The point.
a The triangle's first vertex.
b The triangle's second vertex.
c The triangle's third vertex.
Returns:
If the point resides in the triangle, true is returned.
If the point is outside the triangle, false is returned.

static bool Ogre::Math::pointInTri3D const Vector3 p,
const Vector3 a,
const Vector3 b,
const Vector3 c,
const Vector3 normal
[static]
 

Checks whether a given 3D point is inside a triangle.

Remarks:
The vertices of the triangle must be given in either trigonometrical (anticlockwise) or inverse trigonometrical (clockwise) order, and the point must be guaranteed to be in the same plane as the triangle
Parameters:
p The point.
a The triangle's first vertex.
b The triangle's second vertex.
c The triangle's third vertex.
normal The triangle plane's normal (passed in rather than calculated on demand since the callermay already have it)
Returns:
If the point resides in the triangle, true is returned.
If the point is outside the triangle, false is returned.

static Real Ogre::Math::Pow Real  fBase,
Real  fExponent
[static]
 

Definition at line 250 of file OgreMath.h.

static Real Ogre::Math::RadiansToAngleUnits Real  radians  )  [static]
 

Convert from radians to the current AngleUnit .

Referenced by Ogre::Radian::valueAngleUnits().

static Real Ogre::Math::RadiansToDegrees Real  radians  )  [static]
 

Definition at line 324 of file OgreMath.h.

Referenced by Ogre::Radian::valueDegrees().

static Real Ogre::Math::RangeRandom Real  fLow,
Real  fHigh
[static]
 

static bool Ogre::Math::RealEqual Real  a,
Real  b,
Real  tolerance = std::numeric_limits< Real >::epsilon()
[static]
 

Compare 2 reals, using tolerance for inaccuracies.

Referenced by Ogre::Vector3::positionEquals().

static void Ogre::Math::setAngleUnit AngleUnit  unit  )  [static]
 

These functions used to set the assumed angle units (radians or degrees) expected when using the Angle type.

You can set this directly after creating a new Root, and also before/after resource creation, depending on whether you want the change to affect resource files.

static Degree Ogre::Math::Sign const Degree dValue  )  [static]
 

Definition at line 257 of file OgreMath.h.

References Ogre::Degree::valueDegrees().

static Radian Ogre::Math::Sign const Radian rValue  )  [static]
 

Definition at line 253 of file OgreMath.h.

References Ogre::Radian::valueRadians().

static Real Ogre::Math::Sign Real  fValue  )  [static]
 

static Real Ogre::Math::Sin Real  fValue,
bool  useTables = false
[static]
 

Sine function.

Parameters:
fValue Angle in radians
useTables If true, uses lookup tables rather than calculation - faster but less accurate.

Definition at line 279 of file OgreMath.h.

static Real Ogre::Math::Sin const Radian fValue,
bool  useTables = false
[static]
 

Sine function.

Parameters:
fValue Angle in radians
useTables If true, uses lookup tables rather than calculation - faster but less accurate.

Definition at line 269 of file OgreMath.h.

References Ogre::Radian::valueRadians().

static Real Ogre::Math::SinTable Real  fValue  )  [static, protected]
 

static Real Ogre::Math::Sqr Real  fValue  )  [static]
 

Definition at line 283 of file OgreMath.h.

Referenced by Ogre::Sphere::intersects().

static Degree Ogre::Math::Sqrt const Degree fValue  )  [static]
 

Definition at line 289 of file OgreMath.h.

References Ogre::Degree::valueDegrees().

static Radian Ogre::Math::Sqrt const Radian fValue  )  [static]
 

Definition at line 287 of file OgreMath.h.

References Ogre::Radian::valueRadians().

static Real Ogre::Math::Sqrt Real  fValue  )  [static]
 

Definition at line 285 of file OgreMath.h.

Referenced by Ogre::Vector3::getRotationTo(), Ogre::Vector3::length(), Ogre::Vector2::length(), Ogre::Vector3::normalise(), and Ogre::Vector2::normalise().

static Real Ogre::Math::SymmetricRandom  )  [static]
 

static Real Ogre::Math::Tan Real  fValue,
bool  useTables = false
[static]
 

Tangent function.

Parameters:
fValue Angle in radians
useTables If true, uses lookup tables rather than calculation - faster but less accurate.

Definition at line 319 of file OgreMath.h.

static Real Ogre::Math::Tan const Radian fValue,
bool  useTables = false
[static]
 

Tangent function.

Parameters:
fValue Angle in radians
useTables If true, uses lookup tables rather than calculation - faster but less accurate.

Definition at line 309 of file OgreMath.h.

References Ogre::Radian::valueRadians().

static Real Ogre::Math::TanTable Real  fValue  )  [static, protected]
 

static Real Ogre::Math::UnitRandom  )  [static]
 

Referenced by Ogre::Vector3::randomDeviant(), and Ogre::Vector2::randomDeviant().


Member Data Documentation

const Real Ogre::Math::fDeg2Rad [static]
 

Definition at line 541 of file OgreMath.h.

const Real Ogre::Math::fRad2Deg [static]
 

Definition at line 542 of file OgreMath.h.

const Real Ogre::Math::HALF_PI [static]
 

Definition at line 540 of file OgreMath.h.

AngleUnit Ogre::Math::msAngleUnit [static, protected]
 

Definition at line 181 of file OgreMath.h.

Real* Ogre::Math::mSinTable [static, protected]
 

Definition at line 188 of file OgreMath.h.

Real* Ogre::Math::mTanTable [static, protected]
 

Definition at line 189 of file OgreMath.h.

Real Ogre::Math::mTrigTableFactor [static, protected]
 

Radian -> index factor value ( mTrigTableSize / 2 * PI ).

Definition at line 187 of file OgreMath.h.

int Ogre::Math::mTrigTableSize [static, protected]
 

Size of the trig tables as determined by constructor.

Definition at line 184 of file OgreMath.h.

const Real Ogre::Math::NEG_INFINITY [static]
 

Definition at line 537 of file OgreMath.h.

const Real Ogre::Math::PI [static]
 

Definition at line 538 of file OgreMath.h.

Referenced by Ogre::Vector3::getRotationTo().

const Real Ogre::Math::POS_INFINITY [static]
 

Definition at line 536 of file OgreMath.h.

Referenced by Ogre::MovablePlane::getBoundingRadius().

const Real Ogre::Math::TWO_PI [static]
 

Definition at line 539 of file OgreMath.h.

Referenced by Ogre::Vector3::randomDeviant(), and Ogre::Vector2::randomDeviant().


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

Copyright © 2000-2005 by The OGRE Team
Creative Commons License
This work is licensed under a Creative Commons Attribution-ShareAlike 2.5 License.
Last modified Sun Sep 17 15:40:31 2006