axmol/cocos/math/Vector2.h

765 lines
20 KiB
C++

#ifndef VECTOR2_H_
#define VECTOR2_H_
#include "CCMathBase.h"
#include "base/CCPlatformMacros.h"
#include "2d/ccMacros.h"
NS_CC_MATH_BEGIN
/** Clamp a value between from and to.
*/
inline float clampf(float value, float min_inclusive, float max_inclusive)
{
if (min_inclusive > max_inclusive) {
CC_SWAP(min_inclusive, max_inclusive, float);
}
return value < min_inclusive ? min_inclusive : value < max_inclusive? value : max_inclusive;
}
class Matrix;
/**
* Defines a 2-element floating point vector.
*/
class Vector2
{
public:
/**
* The x coordinate.
*/
float x;
/**
* The y coordinate.
*/
float y;
/**
* Constructs a new vector initialized to all zeros.
*/
Vector2();
/**
* Constructs a new vector initialized to the specified values.
*
* @param xx The x coordinate.
* @param yy The y coordinate.
*/
Vector2(float xx, float yy);
/**
* Constructs a new vector from the values in the specified array.
*
* @param array An array containing the elements of the vector in the order x, y.
*/
Vector2(const float* array);
/**
* Constructs a vector that describes the direction between the specified points.
*
* @param p1 The first point.
* @param p2 The second point.
*/
Vector2(const Vector2& p1, const Vector2& p2);
/**
* Constructs a new vector that is a copy of the specified vector.
*
* @param copy The vector to copy.
*/
Vector2(const Vector2& copy);
/**
* Destructor.
*/
~Vector2();
/**
* Returns the zero vector.
*
* @return The 2-element vector of 0s.
*/
static const Vector2& zero();
/**
* Returns the one vector.
*
* @return The 2-element vector of 1s.
*/
static const Vector2& one();
/**
* Returns the unit x vector.
*
* @return The 2-element unit vector along the x axis.
*/
static const Vector2& unitX();
/**
* Returns the unit y vector.
*
* @return The 2-element unit vector along the y axis.
*/
static const Vector2& unitY();
/**
* Indicates whether this vector contains all zeros.
*
* @return true if this vector contains all zeros, false otherwise.
*/
bool isZero() const;
/**
* Indicates whether this vector contains all ones.
*
* @return true if this vector contains all ones, false otherwise.
*/
bool isOne() const;
/**
* Returns the angle (in radians) between the specified vectors.
*
* @param v1 The first vector.
* @param v2 The second vector.
*
* @return The angle between the two vectors (in radians).
*/
static float angle(const Vector2& v1, const Vector2& v2);
/**
* Adds the elements of the specified vector to this one.
*
* @param v The vector to add.
*/
void add(const Vector2& v);
/**
* Adds the specified vectors and stores the result in dst.
*
* @param v1 The first vector.
* @param v2 The second vector.
* @param dst A vector to store the result in.
*/
static void add(const Vector2& v1, const Vector2& v2, Vector2* dst);
/**
* Clamps this vector within the specified range.
*
* @param min The minimum value.
* @param max The maximum value.
*/
void clamp(const Vector2& min, const Vector2& max);
/**
* Clamps the specified vector within the specified range and returns it in dst.
*
* @param v The vector to clamp.
* @param min The minimum value.
* @param max The maximum value.
* @param dst A vector to store the result in.
*/
static void clamp(const Vector2& v, const Vector2& min, const Vector2& max, Vector2* dst);
/**
* Returns the distance between this vector and v.
*
* @param v The other vector.
*
* @return The distance between this vector and v.
*
* @see distanceSquared
*/
float distance(const Vector2& v) const;
/**
* Returns the squared distance between this vector and v.
*
* When it is not necessary to get the exact distance between
* two vectors (for example, when simply comparing the
* distance between different vectors), it is advised to use
* this method instead of distance.
*
* @param v The other vector.
*
* @return The squared distance between this vector and v.
*
* @see distance
*/
float distanceSquared(const Vector2& v) const;
/**
* Returns the dot product of this vector and the specified vector.
*
* @param v The vector to compute the dot product with.
*
* @return The dot product.
*/
float dot(const Vector2& v) const;
/**
* Returns the dot product between the specified vectors.
*
* @param v1 The first vector.
* @param v2 The second vector.
*
* @return The dot product between the vectors.
*/
static float dot(const Vector2& v1, const Vector2& v2);
/**
* Computes the length of this vector.
*
* @return The length of the vector.
*
* @see lengthSquared
*/
float length() const;
/**
* Returns the squared length of this vector.
*
* When it is not necessary to get the exact length of a
* vector (for example, when simply comparing the lengths of
* different vectors), it is advised to use this method
* instead of length.
*
* @return The squared length of the vector.
*
* @see length
*/
float lengthSquared() const;
/**
* Negates this vector.
*/
void negate();
/**
* Normalizes this vector.
*
* This method normalizes this Vector2 so that it is of
* unit length (in other words, the length of the vector
* after calling this method will be 1.0f). If the vector
* already has unit length or if the length of the vector
* is zero, this method does nothing.
*
* @return This vector, after the normalization occurs.
*/
Vector2& normalize();
/**
* Normalizes this vector and stores the result in dst.
*
* If the vector already has unit length or if the length
* of the vector is zero, this method simply copies the
* current vector into dst.
*
* @param dst The destination vector.
*/
void normalize(Vector2* dst) const;
/**
* Scales all elements of this vector by the specified value.
*
* @param scalar The scalar value.
*/
void scale(float scalar);
/**
* Scales each element of this vector by the matching component of scale.
*
* @param scale The vector to scale by.
*/
void scale(const Vector2& scale);
/**
* Rotates this vector by angle (specified in radians) around the given point.
*
* @param point The point to rotate around.
* @param angle The angle to rotate by (in radians).
*/
void rotate(const Vector2& point, float angle);
/**
* Sets the elements of this vector to the specified values.
*
* @param xx The new x coordinate.
* @param yy The new y coordinate.
*/
void set(float xx, float yy);
/**
* Sets the elements of this vector from the values in the specified array.
*
* @param array An array containing the elements of the vector in the order x, y.
*/
void set(const float* array);
/**
* Sets the elements of this vector to those in the specified vector.
*
* @param v The vector to copy.
*/
void set(const Vector2& v);
/**
* Sets this vector to the directional vector between the specified points.
*
* @param p1 The first point.
* @param p2 The second point.
*/
void set(const Vector2& p1, const Vector2& p2);
/**
* Subtracts this vector and the specified vector as (this - v)
* and stores the result in this vector.
*
* @param v The vector to subtract.
*/
void subtract(const Vector2& v);
/**
* Subtracts the specified vectors and stores the result in dst.
* The resulting vector is computed as (v1 - v2).
*
* @param v1 The first vector.
* @param v2 The second vector.
* @param dst The destination vector.
*/
static void subtract(const Vector2& v1, const Vector2& v2, Vector2* dst);
/**
* Updates this vector towards the given target using a smoothing function.
* The given response time determines the amount of smoothing (lag). A longer
* response time yields a smoother result and more lag. To force this vector to
* follow the target closely, provide a response time that is very small relative
* to the given elapsed time.
*
* @param target target value.
* @param elapsedTime elapsed time between calls.
* @param responseTime response time (in the same units as elapsedTime).
*/
void smooth(const Vector2& target, float elapsedTime, float responseTime);
/**
* Calculates the sum of this vector with the given vector.
*
* Note: this does not modify this vector.
*
* @param v The vector to add.
* @return The vector sum.
*/
inline const Vector2 operator+(const Vector2& v) const;
/**
* Adds the given vector to this vector.
*
* @param v The vector to add.
* @return This vector, after the addition occurs.
*/
inline Vector2& operator+=(const Vector2& v);
/**
* Calculates the sum of this vector with the given vector.
*
* Note: this does not modify this vector.
*
* @param v The vector to add.
* @return The vector sum.
*/
inline const Vector2 operator-(const Vector2& v) const;
/**
* Subtracts the given vector from this vector.
*
* @param v The vector to subtract.
* @return This vector, after the subtraction occurs.
*/
inline Vector2& operator-=(const Vector2& v);
/**
* Calculates the negation of this vector.
*
* Note: this does not modify this vector.
*
* @return The negation of this vector.
*/
inline const Vector2 operator-() const;
/**
* Calculates the scalar product of this vector with the given value.
*
* Note: this does not modify this vector.
*
* @param s The value to scale by.
* @return The scaled vector.
*/
inline const Vector2 operator*(float s) const;
/**
* Scales this vector by the given value.
*
* @param s The value to scale by.
* @return This vector, after the scale occurs.
*/
inline Vector2& operator*=(float s);
/**
* Returns the components of this vector divided by the given constant
*
* Note: this does not modify this vector.
*
* @param s the constant to divide this vector with
* @return a smaller vector
*/
inline const Vector2 operator/(float s) const;
/**
* Determines if this vector is less than the given vector.
*
* @param v The vector to compare against.
*
* @return True if this vector is less than the given vector, false otherwise.
*/
inline bool operator<(const Vector2& v) const;
/**
* Determines if this vector is equal to the given vector.
*
* @param v The vector to compare against.
*
* @return True if this vector is equal to the given vector, false otherwise.
*/
inline bool operator==(const Vector2& v) const;
/**
* Determines if this vector is not equal to the given vector.
*
* @param v The vector to compare against.
*
* @return True if this vector is not equal to the given vector, false otherwise.
*/
inline bool operator!=(const Vector2& v) const;
//code added compatible for Point
public:
/**
* @js NA
* @lua NA
*/
void setPoint(float xx, float yy);
/**
* @js NA
*/
bool equals(const Vector2& target) const;
/** @returns if points have fuzzy equality which means equal with some degree of variance.
@since v2.1.4
* @js NA
* @lua NA
*/
bool fuzzyEquals(const Vector2& target, float variance) const;
/** Calculates distance between point an origin
@return float
@since v2.1.4
* @js NA
* @lua NA
*/
inline float getLength() const {
return sqrtf(x*x + y*y);
};
/** Calculates the square length of a Vector2 (not calling sqrt() )
@return float
@since v2.1.4
* @js NA
* @lua NA
*/
inline float getLengthSq() const {
return dot(*this); //x*x + y*y;
};
/** Calculates the square distance between two points (not calling sqrt() )
@return float
@since v2.1.4
* @js NA
* @lua NA
*/
inline float getDistanceSq(const Vector2& other) const {
return (*this - other).getLengthSq();
};
/** Calculates the distance between two points
@return float
@since v2.1.4
* @js NA
* @lua NA
*/
inline float getDistance(const Vector2& other) const {
return (*this - other).getLength();
};
/** @returns the angle in radians between this vector and the x axis
@since v2.1.4
* @js NA
* @lua NA
*/
inline float getAngle() const {
return atan2f(y, x);
};
/** @returns the angle in radians between two vector directions
@since v2.1.4
* @js NA
* @lua NA
*/
float getAngle(const Vector2& other) const;
/** Calculates cross product of two points.
@return float
@since v2.1.4
* @js NA
* @lua NA
*/
inline float cross(const Vector2& other) const {
return x*other.y - y*other.x;
};
/** Calculates perpendicular of v, rotated 90 degrees counter-clockwise -- cross(v, perp(v)) >= 0
@return Vector2
@since v2.1.4
* @js NA
* @lua NA
*/
inline Vector2 getPerp() const {
return Vector2(-y, x);
};
/** Calculates midpoint between two points.
@return Vector2
@since v3.0
* @js NA
* @lua NA
*/
inline Vector2 getMidpoint(const Vector2& other) const
{
return Vector2((x + other.x) / 2.0f, (y + other.y) / 2.0f);
}
/** Clamp a point between from and to.
@since v3.0
* @js NA
* @lua NA
*/
inline Vector2 getClampPoint(const Vector2& min_inclusive, const Vector2& max_inclusive) const
{
return Vector2(clampf(x,min_inclusive.x,max_inclusive.x), clampf(y, min_inclusive.y, max_inclusive.y));
}
/** Run a math operation function on each point component
* absf, fllorf, ceilf, roundf
* any function that has the signature: float func(float);
* For example: let's try to take the floor of x,y
* p.compOp(floorf);
@since v3.0
* @js NA
* @lua NA
*/
inline Vector2 compOp(std::function<float(float)> function) const
{
return Vector2(function(x), function(y));
}
/** Calculates perpendicular of v, rotated 90 degrees clockwise -- cross(v, rperp(v)) <= 0
@return Vector2
@since v2.1.4
* @js NA
* @lua NA
*/
inline Vector2 getRPerp() const {
return Vector2(y, -x);
};
/** Calculates the projection of this over other.
@return Vector2
@since v2.1.4
* @js NA
* @lua NA
*/
inline Vector2 project(const Vector2& other) const {
return other * (dot(other)/other.dot(other));
};
/** Complex multiplication of two points ("rotates" two points).
@return Vector2 vector with an angle of this.getAngle() + other.getAngle(),
and a length of this.getLength() * other.getLength().
@since v2.1.4
* @js NA
* @lua NA
*/
inline Vector2 rotate(const Vector2& other) const {
return Vector2(x*other.x - y*other.y, x*other.y + y*other.x);
};
/** Unrotates two points.
@return Vector2 vector with an angle of this.getAngle() - other.getAngle(),
and a length of this.getLength() * other.getLength().
@since v2.1.4
* @js NA
* @lua NA
*/
inline Vector2 unrotate(const Vector2& other) const {
return Vector2(x*other.x + y*other.y, y*other.x - x*other.y);
};
/** Returns point multiplied to a length of 1.
* If the point is 0, it returns (1, 0)
@return Vector2
@since v2.1.4
* @js NA
* @lua NA
*/
inline Vector2 normalize() const {
float length = getLength();
if(length == 0.) return Vector2(1.f, 0);
return *this / getLength();
};
/** Linear Interpolation between two points a and b
@returns
alpha == 0 ? a
alpha == 1 ? b
otherwise a value between a..b
@since v2.1.4
* @js NA
* @lua NA
*/
inline Vector2 lerp(const Vector2& other, float alpha) const {
return *this * (1.f - alpha) + other * alpha;
};
/** Rotates a point counter clockwise by the angle around a pivot
@param pivot is the pivot, naturally
@param angle is the angle of rotation ccw in radians
@returns the rotated point
@since v2.1.4
* @js NA
* @lua NA
*/
Vector2 rotateByAngle(const Vector2& pivot, float angle) const;
/**
* @js NA
* @lua NA
*/
static inline Vector2 forAngle(const float a)
{
return Vector2(cosf(a), sinf(a));
}
/** A general line-line intersection test
@param A the startpoint for the first line L1 = (A - B)
@param B the endpoint for the first line L1 = (A - B)
@param C the startpoint for the second line L2 = (C - D)
@param D the endpoint for the second line L2 = (C - D)
@param S the range for a hitpoint in L1 (p = A + S*(B - A))
@param T the range for a hitpoint in L2 (p = C + T*(D - C))
@returns whether these two lines interects.
Note that to truly test intersection for segments we have to make
sure that S & T lie within [0..1] and for rays, make sure S & T > 0
the hit point is C + T * (D - C);
the hit point also is A + S * (B - A);
@since 3.0
* @js NA
* @lua NA
*/
static bool isLineIntersect(const Vector2& A, const Vector2& B,
const Vector2& C, const Vector2& D,
float *S = nullptr, float *T = nullptr);
/**
returns true if Line A-B overlap with segment C-D
@since v3.0
* @js NA
* @lua NA
*/
static bool isLineOverlap(const Vector2& A, const Vector2& B,
const Vector2& C, const Vector2& D);
/**
returns true if Line A-B parallel with segment C-D
@since v3.0
* @js NA
* @lua NA
*/
static bool isLineParallel(const Vector2& A, const Vector2& B,
const Vector2& C, const Vector2& D);
/**
returns true if Segment A-B overlap with segment C-D
@since v3.0
* @js NA
* @lua NA
*/
static bool isSegmentOverlap(const Vector2& A, const Vector2& B,
const Vector2& C, const Vector2& D,
Vector2* S = nullptr, Vector2* E = nullptr);
/**
returns true if Segment A-B intersects with segment C-D
@since v3.0
* @js NA
* @lua NA
*/
static bool isSegmentIntersect(const Vector2& A, const Vector2& B, const Vector2& C, const Vector2& D);
/**
returns the intersection point of line A-B, C-D
@since v3.0
* @js NA
* @lua NA
*/
static Vector2 getIntersectPoint(const Vector2& A, const Vector2& B, const Vector2& C, const Vector2& D);
/** equals to Vector2(0,0) */
static const Vector2 ZERO;
/** equals to Vector2(0.5, 0.5) */
static const Vector2 ANCHOR_MIDDLE;
/** equals to Vector2(0, 0) */
static const Vector2 ANCHOR_BOTTOM_LEFT;
/** equals to Vector2(0, 1) */
static const Vector2 ANCHOR_TOP_LEFT;
/** equals to Vector2(1, 0) */
static const Vector2 ANCHOR_BOTTOM_RIGHT;
/** equals to Vector2(1, 1) */
static const Vector2 ANCHOR_TOP_RIGHT;
/** equals to Vector2(1, 0.5) */
static const Vector2 ANCHOR_MIDDLE_RIGHT;
/** equals to Vector2(0, 0.5) */
static const Vector2 ANCHOR_MIDDLE_LEFT;
/** equals to Vector2(0.5, 1) */
static const Vector2 ANCHOR_MIDDLE_TOP;
/** equals to Vector2(0.5, 0) */
static const Vector2 ANCHOR_MIDDLE_BOTTOM;
};
/**
* Calculates the scalar product of the given vector with the given value.
*
* @param x The value to scale by.
* @param v The vector to scale.
* @return The scaled vector.
*/
inline const Vector2 operator*(float x, const Vector2& v);
NS_CC_MATH_END
#include "Vector2.inl"
#endif