[SML Overview]

# class SMLVec2f

    #include "smlmath.h"

Class SMLVec2f is a 2x1 vector of single precision floats. It includes data and methods, which allow forming 2-vectors, computing sum, difference, finding normalized vector, etc.

## Public Interface

### Constructors

constructors

### Access the data as an array

data

### Rename to XY

X | Y

### Operators

operator= | operator+ | operator-
operator* | operator/ | operator+=
operator-= | operator*= | operator/=

### Methods

Add | Sub | Scale
Dot | Negate | Length
LengthSquared | Distance | DistanceSquared
Normalize | operator< | operator==
operator!=

## Public Data

float x;

float y;

Defines 2 components of the vector.

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SMLLIBENTRY SMLVec2f(float a, float b);

#### Discussion

SMLVec2f object constructor. This constructor sets coordinates of vector equal to a, b correspondingly.

Example:

    SMLVec2f A(3.5f, 0.45f);

#### Parameters

a, b - coordinates of new vector. These parameters should be of float type.

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SMLLIBENTRY SMLVec2f(float v[]);

#### Discussion

SMLVec2f object constructor. The constructor sets the coordinates of vector equal to first two elements of float-type array v.

Example:

    float crd[2] = {1, 3}; SMLVec2f A(crd);

#### Parameters

v[] - float-type array with coordinates of new vector. The array must have at least two elements.

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#### Discussion

SMLLIBENTRY SMLVec2f(const SMLVec2f& v);

SMLVec2f copy-constructor. The constructor sets coordinates of vector equal to those of vector v.

Example:

    float crd[2] = {1, 3};
    SMLVec2f A(crd);
    SMLVec2f B(A);

#### Parameters

v - reference to an object of SMLVec2f type.

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SMLLIBENTRY SMLVec2f();

#### Discussion

Default SMLVec2f object constructor. The constructor sets all coordinates of vector equal to zero.

Example:

    SMLVec2f A();

#### Parameters

No.

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SMLLIBENTRY const float* data() const;

SMLLIBENTRY float* data();

#### Discussion

Methods are used for access to component data of the object, which are coordinates of a vector.

Example:

    float *tmp, crd[2] = {1, 3};
    SMLVec2f A(crd);
    tmp = A.data(); // tmp[1] = 3

#### Parameters

No.

#### Return Value

Methods return float-type pointer to the first element of component data of the object.

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SMLLIBENTRY float X() const;

#### Discussion

Method is used for access to variable x of component data of the object. This variable is x - coordinate of the current vector.

Example:

    float tmp, crd[2] = {1, 3};
    SMLVec2f A(crd);
    tmp = A.X(); // tmp = 1

#### Parameters

No.

#### Return Value

Methods returns value of variable x of component data of the object.

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SMLLIBENTRY float& X();

#### Discussion

Method is used as synonym of variable x of component data of the object.

#### Parameters

No.

#### Return Value

Methods returns reference to variable x of component data of the object.

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SMLLIBENTRY float Y() const;

#### Discussion

Method is used for access to variable y of component data of the object. This variable is y - coordinate of the current vector.

Example:

    float tmp, crd[2] = {1, 3};
    SMLVec2f A(crd);
    tmp = A.Y(); // tmp = 3

#### Parameters

No.

#### Return Value

Methods returns value of variable y of component data of the object. This variable is y - coordinate of the current vector.

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SMLLIBENTRY float& Y();

#### Discussion

Method is used as synonym of variable y of component data of the object.

#### Parameters

No.

#### Return Value

Methods returns reference to variable y of component data of the object.

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SMLLIBENTRY const SMLVec2f& operator=(const SMLVec2f& v);

#### Discussion

Method is an overloaded operator-function. It sets coordinates of this vector to those of vector v.

Example:

    float crd[2] = {1, 3};
    SMLVec2f A(crd), B;
    B = A;

#### Parameters

v - reference to object of SMLVec2f type whose coordinates are assigned to the new vector.

#### Return Value

Returns reference to SMLVec2f-type object.

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friend SMLLIBENTRY bool operator<(const SMLVec2f& v1, const SMLVec2f& v2);

#### Discussion

Friend of the class. Function compares length of 2 vectors and returns true, if and only if vector v1 is shorter than v2.

Example:

    float crd1[2] = {1, 2}, crd2[2] = {2, 2};
    SMLVec2f A(crd1), B(crd2);
    A = (A > B)?A:B // A = B

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friend SMLLIBENTRY bool operator==(const SMLVec2f& v1, const SMLVec2f& v2);

#### Discussion

Friend of the class. Function returns true, if components of two vectors are equal to each other.

Example:

    float crd1[2] = {1, 2}, crd2[2] = {2, 2};
    SMLVec2f A(crd1), B(crd2);
    A = (A == B)?A:B // A = B

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friend SMLLIBENTRY bool operator!=(const SMLVec2f& v1, const SMLVec2f& v2);

#### Discussion

Friend of the class. Function returns true, if components of 2 vectors are not equal.

Example:

    float crd1[2] = {1, 2}, crd2[2] = {2, 2};
    SMLVec2f A(crd1), B(crd2);
    A = (A != B)?A:B // A = A

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SMLLIBENTRY SMLVec2f operator+(const SMLVec2f& v) const;

#### Discussion

Method is an overloaded operator-function. It computes and returns sum of this vector and vector v.

Example:

    float crd1[2] = {1, 3}, crd2[2] = {2, 2};
    SMLVec2f A(crd1), B(crd2), C;
    C = A + B // C = {3, 5}

#### Parameters

v - reference to object of SMLVec2f type.

#### Return Value

Returns new object of SMLVec2f type, which is equal to sum of two vectors.

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SMLLIBENTRY SMLVec2f operator-(const SMLVec2f& v) const;

#### Discussion

Method is an overloaded operator-function. It computes and returns difference of this vector and vector v.

Example:

    float crd1[2] = {1, 3}, crd2[2] = {2, 2};
    SMLVec2f A(crd1), B(crd2), C;
    C = A - B // C = {-1, 1}

#### Parameters

v - reference to object of SMLVec2f type.

#### Return Value

Returns new object of SMLVec2f type, which is equal to difference of two vectors.

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SMLLIBENTRY SMLVec2f operator*(float var) const;

#### Discussion

Method is an overloaded operator-function. It computes and returns product of vector and variable var.

Example:

    float crd[2] = {1, 3};
    SMLVec2f A(crd), C;
    C = A * 2.0f // C = {2, 6}

#### Parameters

var - variable of float type.

#### Return Value

Returns new object of SMLVec2f type, which is equal to product of vector and variable.

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SMLLIBENTRY SMLVec2f operator/(float var) const;

#### Discussion

Method is an overloaded operator-function. It computes and returns quotient of vector and variable var.

Example:

    float crd[2] = {1, 3};
    SMLVec2f A(crd), C;
    C = A / 2.0f // C = {0.5, 1.5}

#### Parameters

var - variable of float type.

#### Return Value

Returns new object of SMLVec2f type, which is quotient of vector and variable.

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SMLLIBENTRY SMLVec2f& operator+=(const SMLVec2f& v);

#### Discussion

Method is an overloaded operator-function. It computes sum of two vectors. The result is assigned to this vector.

Example:

    float crd1[2] = {1, 3}, crd2[2] = {2, 2};
    SMLVec2f A(crd1), B(crd2);
    A += B // A = {3, 5}

#### Parameters

v - reference to object of SMLVec2f type.

#### Return Value

Returns reference to current object of SMLVec2f type, which is sum of two vectors.

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SMLLIBENTRY SMLVec2f& operator-=(const SMLVec2f& v);

#### Discussion

Method is an overloaded operator-function. It computes difference of two vectors. The result is assigned to this vector.

Example:

    float crd1[2] = {1, 3}, crd2[2] = {2, 2};
    SMLVec2f A(crd1), B(crd2);
    A -= B // C = {-1, 1}

#### Parameters

v - reference to object of SMLVec2f type.

#### Return Value

Returns reference to current object of SMLVec2f type, which is difference of two vectors.

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SMLLIBENTRY SMLVec2f& operator*=(float var);

#### Discussion

Method is an overloaded operator-function. It computes product of vector and variable. The result is assigned to this vector.

Example:

    float crd[2] = {1, 3};
    SMLVec2f A(crd);
    A *= 2.0f // C = {2, 6}

#### Parameters

v - reference to object of SMLVec2f type.

#### Return Value

Returns reference to the current object of SMLVec2f type, which is product of two vectors.

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SMLLIBENTRY SMLVec2f& operator/=(float var);

#### Discussion

Method is an overloaded operator-function. It computes quotient of vector and variable. The result is assigned to this vector.

Example:

    float crd[2] = {1, 3};
    SMLVec2f A(crd);
    A /= 2.0f // C = {0.5, 1.5}

#### Parameters

var - reference to object of SMLVec2f type.

#### Return Value

Returns reference to the current object of SMLVec2f type, which is quotient of the vector and variable.

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SMLLIBENTRY void Add(const SMLVec2f& vec1, const SMLVec2f& vec2);

#### Discussion

Method sets coordinates of this vector equal to sum of corresponding coordinates of two vectors vec1 and vec2

Example:

    float crd1[2] = {1, 3}, crd2[2] = {2, 2};
    SMLVec2f A(crd1), B(crd2), C;
    C.Add(A, B); // C = {3, 5}

#### Parameters

vec1, vec2 - vectors to be added .

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SMLLIBENTRY void Sub(const SMLVec2f& vec1, const SMLVec2f& vec2);

#### Discussion

Method sets coordinates of this vector equal to difference of corresponding coordinates of two vectors vec1 and vec2

Example:

    float crd1[2] = {1, 3}, crd2[2] = {2, 2};
    SMLVec2f A(crd1), B(crd2), C;
    C.Sub(A,B); // C = {-1, 1}

#### Parameters

vec1, vec2 - vectors, difference of which is to be computed.

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SMLLIBENTRY void Scale(float var, const SMLVec2f& v);

#### Discussion

Method sets coordinates of vector equal to product of variable var and vector v.

Example:

    float crd[2] = {1, 3};
    SMLVec2f A(crd1);
    A.Scale(2.0f); // A = {2, 6}

#### Parameters

var - variable of float type (scale parameter).

v - reference to vector to be scaled.

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SMLLIBENTRY float Dot(const SMLVec2f& vec) const;

#### Discussion

Method computes scalar product of this vector and vector vec.

Example:

    float sp, crd1[2] = {1, 3}, crd2[2] = {2, 2};
    SMLVec2f A(crd1), B(crd2);
    sp = A.Dot(B); // sp = 8

#### Parameters

vec - reference to the second vector of the scalar product.

#### Return Value

Returns scalar product of this vector and vector vec.

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SMLLIBENTRY float Dot(const float * const vec) const;

#### Discussion

Method computes scalar product of this vector and vector defined by float array vec.

Example:

    float sp, crd1[2] = {1, 3}, crd2[2] = {2, 2};
    SMLVec2f A(crd1);
    sp = A.Dot(crd2); // sp = 8

#### Parameters

vec - constant pointer to the second constant vector of the scalar product.

#### Return Value

Returns scalar product of this vector and vector vec.

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SMLLIBENTRY const SMLVec2f& Negate();

#### Discussion

Method replaces this vector with vector (-x, -y).

Example:

    SMLVec2f A(1,3); A.Negate(); // A = {-1, -3}

#### Parameters

No.

#### Return Value

Methods returns reference to the current object.

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SMLLIBENTRY float Length() const;

#### Discussion

Method computes length of this vector.

Example:

    float l;
    SMLVec2f A(3,4); l = A.Length(); // l = 5

#### Parameters

No.

#### Return Value

Methods returns length of this vector.

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SMLLIBENTRY float LengthSquared() const;

#### Discussion

Method computes length squared of this vector.

Example:

    float ls;
    SMLVec2f A(3,4); ls = A.LengthSquared(); // ls = 25

#### Parameters

No.

#### Return Value

Methods returns length squared of this vector.

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SMLLIBENTRY float Distance(const SMLVec2f& vec) const;

#### Discussion

Method computes distance between this vector (considered as a point) and vector vec.

Example:

    float d;
    SMLVec2f A(3,4), B(4,3);
    d = A.Distance(B); // d = 1

#### Parameters

vec - radius-vector of the second point. Reference to object of SMLVec2f type.

#### Return Value

Methods returns distance between two points.

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SMLLIBENTRY float DistanceSquared(const SMLVec2f& vec) const;

#### Discussion

Method computes distance squared between this point and vector vec.

Example:

    float ds;
    SMLVec2f A(2,4), B(4,3);
    ds = A.Distance(B); // ds = 5

#### Parameters

vec - radius-vector of the second point. Reference to object of SMLVec2f type.

#### Return Value

Methods returns distance squared between two points.

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SMLLIBENTRY floatoperator*(const SMLVec2f& vec) const;

#### Discussion

Method is an overloaded operator-function. It computes scalar product of the component this vector and vector vec.

Example:

    float sp;
    SMLVec2f A(1,2), B(2,2);
    sp = A * B; // sp = 5

#### Parameters

vec - reference to object of SMLVec2f type.

#### Return Value

Returns scalar product of the vectors.

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SMLLIBENTRY float Normalize();

#### Discussion

Method normalizes this vector. If length of the vector is smaller than 1 / FLT_EPSILON, the normalized vector is created in accordance with general rules, i. e. normalized vector is equal to this vector divided on its length. If norm of the vector is greater than 1 / FLT_EPSILON, the method forms unit vector with coordinates {0; 1}.

Example:

    float n;
    SMLVec2f A(3,4);
    n = A.Normalize(); // n = 5, A = {0.6, 0.8}

#### Parameters

No.

#### Return Value

Methods returns value equal to the inverted length of this vector.

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