class Vector2D

Defined in: C4Vector2D.h

The Vector2D class encapsulates a 2D vector.

Definition

class Vector2D

Member Functions

`Vector2D::Set`	Sets both components of a vector.
`Vector2D::Normalize`	Normalizes a 2D vector.
`Vector2D::Rotate`	Rotates a vector in the x-y plane.

Data Members

`float x;`	The x coordinate.
`float y;`	The y coordinate.

Constructor

Vector2D();

Vector2D(float r, float s);

Parameters

`r`	The value of the x coordinate.
`s`	The value of the y coordinate.

Description

The Vector2D class is used to store a two-dimensional direction vector having floating-point components x and y. A direction vector stored in this class is assumed to have a w coordinate of 0 whenever it needs to be converted to a four-dimensional representation. Two-dimensional points (for which the w coordinate is 1) should be stored using the Point2D class. The z coordinate of a 2D vector is always assumed to be 0.

The default constructor leaves the components of the vector undefined. If the values r and s are supplied, then they are assigned to the x and y components of the vector, respectively.

Overloaded Operators

`float& operator [](long k);`	Returns a reference to the `k`-th component of a vector. The value of `k` must be 0 or 1.
`const float& operator [](long k) const;`	Returns a constant reference to the `k`-th component of a vector. The value of `k` must be 0 or 1.
`Vector2D& operator +=(const Vector2D& v);`	Adds the vector `v`.
`Vector2D& operator -=(const Vector2D& v);`	Subtracts the vector `v`.
`Vector2D& operator *=(float t);`	Multiplies by the scalar `t`.
`Vector2D& operator /=(float t);`	Divides by the scalar `t`.
`Vector2D& operator &=(const Vector2D& v);`	Calculates the componentwise product with the vector `v`.

Nonmember Operations

`Vector2D operator -(const Vector2D& v) const;`	Returns the negation of the vector `v`.
`Vector2D operator +(const Vector2D& v1, const Vector2D& v2) const;`	Returns the sum of the vectors `v1` and `v2`.
`Vector2D operator -(const Vector2D& v1, const Vector2D& v2) const;`	Returns the difference of the vectors `v1` and `v2`.
`Vector2D operator *(const Vector2D& v, float t) const;`	Returns the product of the vector `v` and the scalar `t`.
`Vector2D operator *(float t, const Vector2D& v);`	Returns the product of the vector `v` and the scalar `t`.
`Vector2D operator /(const Vector2D& v, float t) const;`	Returns the product of the vector `v` and the inverse of the scalar `t`.
`float operator *(const Vector2D& v1, const Vector2D& v2) const;`	Returns the dot product of the vectors `v1` and `v2`.
`Vector2D operator &(const Vector2D& v1, const Vector2D& v2) const;`	Returns the componentwise product of the vectors `v1` and `v2`.
`bool operator ==(const Vector2D& v1, const Vector2D& v2) const;`	Returns a boolean value indicating the equality of the two vectors `v1` and `v2`.
`bool operator !=(const Vector2D& v1, const Vector2D& v2) const;`	Returns a boolean value indicating the inequality of the two vectors `v1` and `v2`.
`float Dot(const Vector2D& v1, const Vector2D& v2);`	Returns the dot product between `v1` and `v2`.
`Vector2D ProjectOnto(const Vector2D& v1, const Vector2D& v2);`	Returns the projection of `v1` onto `v2` scaled by the squared magnitude of `v2`.
`float Magnitude(const Vector2D& v);`	Returns the magnitude of the vector `v`.
`float InverseMag(const Vector2D& v);`	Returns the inverse magnitude of the vector `v`.
`float SquaredMag(const Vector2D& v);`	Returns the squared magnitude of the vector `v`.