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cocos2d-x math之Vec4封装

作者:互联网

Vec4.h源代码如下:

#ifndef MATH_VEC4_H
#define MATH_VEC4_H

#define MATH_FLOAT_SMALL            1.0e-37f
#define MATH_TOLERANCE              2e-37f


#ifndef CCASSERT
#if COCOS2D_DEBUG > 0
// todo: minggo
// #if CC_ENABLE_SCRIPT_BINDING
// extern bool CC_DLL cc_assert_script_compatible(const char *msg);
// #define CCASSERT(cond, msg) do {                              \
    //       if (!(cond)) {                                          \
    //         if (!cc_assert_script_compatible(msg) && strlen(msg)) \
    //           cocos2d::log("Assert failed: %s", msg);             \
    //         CC_ASSERT(cond);                                      \
    //       } \
    //     } while (0)
	// #else
#define CCASSERT(cond, msg) CC_ASSERT(cond)
// #endif
#else
#define CCASSERT(cond, msg)
#endif

#define GP_ASSERT(cond) CCASSERT(cond, "")
#endif // CCASSERT


class Mat4;

/**
 * Defines 4-element floating point vector.
 */
class  Vec4
{
public:
#ifdef __SSE__
	union {
		struct {
			float x;
			float y;
			float z;
			float w;
		};
		__m128 v;
	};
#else
	/**
	 * The x-coordinate.
	 */
	float x;

	/**
	 * The y-coordinate.
	 */
	float y;

	/**
	 * The z-coordinate.
	 */
	float z;

	/**
	 * The w-coordinate.
	 */
	float w;
#endif
	/**
	 * Constructs a new vector initialized to all zeros.
	 */
	Vec4();

	/**
	 * Constructs a new vector initialized to the specified values.
	 *
	 * @param xx The x coordinate.
	 * @param yy The y coordinate.
	 * @param zz The z coordinate.
	 * @param ww The w coordinate.
	 */
	Vec4(float xx, float yy, float zz, float ww);

	/**
	 * 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, z, w.
	 */
	Vec4(const float* array);

	/**
	 * Constructs a vector that describes the direction between the specified points.
	 *
	 * @param p1 The first point.
	 * @param p2 The second point.
	 */
	Vec4(const Vec4& p1, const Vec4& p2);

	/**
	 * Constructor.
	 *
	 * Creates a new vector that is a copy of the specified vector.
	 *
	 * @param copy The vector to copy.
	 */
	Vec4(const Vec4& copy);

	/**
	 * Creates a new vector from an integer interpreted as an RGBA value.
	 * E.g. 0xff0000ff represents opaque red or the vector (1, 0, 0, 1).
	 *
	 * @param color The integer to interpret as an RGBA value.
	 *
	 * @return A vector corresponding to the interpreted RGBA color.
	 */
	static Vec4 fromColor(unsigned int color);

	/**
	 * Destructor.
	 */
	~Vec4();

	/**
	 * 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 Vec4& v1, const Vec4& v2);

	/**
	 * Adds the elements of the specified vector to this one.
	 *
	 * @param v The vector to add.
	 */
	void add(const Vec4& 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 Vec4& v1, const Vec4& v2, Vec4* dst);

	/**
	 * Clamps this vector within the specified range.
	 *
	 * @param min The minimum value.
	 * @param max The maximum value.
	 */
	void clamp(const Vec4& min, const Vec4& 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 Vec4& v, const Vec4& min, const Vec4& max, Vec4* 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 Vec4& 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 Vec4& 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 Vec4& 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 Vec4& v1, const Vec4& 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 Vec4 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.
	 */
	void normalize();

	/**
	 * Get the normalized vector.
	 */
	Vec4 getNormalized() const;

	/**
	 * Scales all elements of this vector by the specified value.
	 *
	 * @param scalar The scalar value.
	 */
	void scale(float scalar);

	/**
	 * Sets the elements of this vector to the specified values.
	 *
	 * @param xx The new x coordinate.
	 * @param yy The new y coordinate.
	 * @param zz The new z coordinate.
	 * @param ww The new w coordinate.
	 */
	void set(float xx, float yy, float zz, float ww);

	/**
	 * 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, z, w.
	 */
	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 Vec4& 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 Vec4& p1, const Vec4& 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 Vec4& 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 Vec4& v1, const Vec4& v2, Vec4* dst);

	/**
	 * 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 Vec4 operator+(const Vec4& v) const;

	/**
	 * Adds the given vector to this vector.
	 *
	 * @param v The vector to add.
	 * @return This vector, after the addition occurs.
	 */
	inline Vec4& operator+=(const Vec4& 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 Vec4 operator-(const Vec4& v) const;

	/**
	 * Subtracts the given vector from this vector.
	 *
	 * @param v The vector to subtract.
	 * @return This vector, after the subtraction occurs.
	 */
	inline Vec4& operator-=(const Vec4& v);

	/**
	 * Calculates the negation of this vector.
	 *
	 * Note: this does not modify this vector.
	 *
	 * @return The negation of this vector.
	 */
	inline const Vec4 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 Vec4 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 Vec4& 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 Vec4 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 Vec4& 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 Vec4& 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 Vec4& v) const;

	/** equals to Vec4(0,0,0,0) */
	static const Vec4 ZERO;
	/** equals to Vec4(1,1,1,1) */
	static const Vec4 ONE;
	/** equals to Vec4(1,0,0,0) */
	static const Vec4 UNIT_X;
	/** equals to Vec4(0,1,0,0) */
	static const Vec4 UNIT_Y;
	/** equals to Vec4(0,0,1,0) */
	static const Vec4 UNIT_Z;
	/** equals to Vec4(0,0,0,1) */
	static const Vec4 UNIT_W;
};

/**
 * 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 Vec4 operator*(float x, const Vec4& v);


#include "Vec4.inl"

#endif // MATH_VEC4_H

Vec4.inl源代码如下:

#include "Vec4.h"


inline const Vec4 Vec4::operator+(const Vec4& v) const
{
	Vec4 result(*this);
	result.add(v);
	return result;
}

inline Vec4& Vec4::operator+=(const Vec4& v)
{
	add(v);
	return *this;
}

inline const Vec4 Vec4::operator-(const Vec4& v) const
{
	Vec4 result(*this);
	result.subtract(v);
	return result;
}

inline Vec4& Vec4::operator-=(const Vec4& v)
{
	subtract(v);
	return *this;
}

inline const Vec4 Vec4::operator-() const
{
	Vec4 result(*this);
	result.negate();
	return result;
}

inline const Vec4 Vec4::operator*(float s) const
{
	Vec4 result(*this);
	result.scale(s);
	return result;
}

inline Vec4& Vec4::operator*=(float s)
{
	scale(s);
	return *this;
}

inline const Vec4 Vec4::operator/(const float s) const
{
	return Vec4(this->x / s, this->y / s, this->z / s, this->w / s);
}

inline bool Vec4::operator<(const Vec4& v) const
{
	if (x == v.x)
	{
		if (y == v.y)
		{
			if (z < v.z)
			{
				if (w < v.w)
				{
					return w < v.w;
				}
			}
			return z < v.z;
		}
		return y < v.y;
	}
	return x < v.x;
}

inline bool Vec4::operator==(const Vec4& v) const
{
	return x == v.x && y == v.y && z == v.z && w == v.w;
}

inline bool Vec4::operator!=(const Vec4& v) const
{
	return x != v.x || y != v.y || z != v.z || w != v.w;
}

inline const Vec4 operator*(float x, const Vec4& v)
{
	Vec4 result(v);
	result.scale(x);
	return result;
}

vec4.cpp代码如下:

#include "Vec4.h"
#include <cmath>



Vec4::Vec4()
	: x(0.0f), y(0.0f), z(0.0f), w(0.0f)
{
}

Vec4::Vec4(float xx, float yy, float zz, float ww)
	: x(xx), y(yy), z(zz), w(ww)
{
}

Vec4::Vec4(const float* src)
{
	set(src);
}

Vec4::Vec4(const Vec4& p1, const Vec4& p2)
{
	set(p1, p2);
}

Vec4::Vec4(const Vec4& copy)
{
	set(copy);
}

Vec4 Vec4::fromColor(unsigned int color)
{
	float components[4];
	int componentIndex = 0;
	for (int i = 3; i >= 0; --i)
	{
		int component = (color >> i * 8) & 0x000000ff;

		components[componentIndex++] = static_cast<float>(component) / 255.0f;
	}

	Vec4 value(components);
	return value;
}

Vec4::~Vec4()
{
}

bool Vec4::isZero() const
{
	return x == 0.0f && y == 0.0f && z == 0.0f && w == 0.0f;
}

bool Vec4::isOne() const
{
	return x == 1.0f && y == 1.0f && z == 1.0f && w == 1.0f;
}

float Vec4::angle(const Vec4& v1, const Vec4& v2)
{
	float dx = v1.w * v2.x - v1.x * v2.w - v1.y * v2.z + v1.z * v2.y;
	float dy = v1.w * v2.y - v1.y * v2.w - v1.z * v2.x + v1.x * v2.z;
	float dz = v1.w * v2.z - v1.z * v2.w - v1.x * v2.y + v1.y * v2.x;

	return std::atan2(std::sqrt(dx * dx + dy * dy + dz * dz) + MATH_FLOAT_SMALL, dot(v1, v2));
}

void Vec4::add(const Vec4& v)
{
	x += v.x;
	y += v.y;
	z += v.z;
	w += v.w;
}

void Vec4::add(const Vec4& v1, const Vec4& v2, Vec4* dst)
{
	GP_ASSERT(dst);

	dst->x = v1.x + v2.x;
	dst->y = v1.y + v2.y;
	dst->z = v1.z + v2.z;
	dst->w = v1.w + v2.w;
}

void Vec4::clamp(const Vec4& min, const Vec4& max)
{
	GP_ASSERT(!(min.x > max.x || min.y > max.y || min.z > max.z || min.w > max.w));

	// Clamp the x value.
	if (x < min.x)
		x = min.x;
	if (x > max.x)
		x = max.x;

	// Clamp the y value.
	if (y < min.y)
		y = min.y;
	if (y > max.y)
		y = max.y;

	// Clamp the z value.
	if (z < min.z)
		z = min.z;
	if (z > max.z)
		z = max.z;

	// Clamp the z value.
	if (w < min.w)
		w = min.w;
	if (w > max.w)
		w = max.w;
}

void Vec4::clamp(const Vec4& v, const Vec4& min, const Vec4& max, Vec4* dst)
{
	GP_ASSERT(dst);
	GP_ASSERT(!(min.x > max.x || min.y > max.y || min.z > max.z || min.w > max.w));

	// Clamp the x value.
	dst->x = v.x;
	if (dst->x < min.x)
		dst->x = min.x;
	if (dst->x > max.x)
		dst->x = max.x;

	// Clamp the y value.
	dst->y = v.y;
	if (dst->y < min.y)
		dst->y = min.y;
	if (dst->y > max.y)
		dst->y = max.y;

	// Clamp the z value.
	dst->z = v.z;
	if (dst->z < min.z)
		dst->z = min.z;
	if (dst->z > max.z)
		dst->z = max.z;

	// Clamp the w value.
	dst->w = v.w;
	if (dst->w < min.w)
		dst->w = min.w;
	if (dst->w > max.w)
		dst->w = max.w;
}

float Vec4::distance(const Vec4& v) const
{
	float dx = v.x - x;
	float dy = v.y - y;
	float dz = v.z - z;
	float dw = v.w - w;

	return std::sqrt(dx * dx + dy * dy + dz * dz + dw * dw);
}

float Vec4::distanceSquared(const Vec4& v) const
{
	float dx = v.x - x;
	float dy = v.y - y;
	float dz = v.z - z;
	float dw = v.w - w;

	return (dx * dx + dy * dy + dz * dz + dw * dw);
}

float Vec4::dot(const Vec4& v) const
{
	return (x * v.x + y * v.y + z * v.z + w * v.w);
}

float Vec4::dot(const Vec4& v1, const Vec4& v2)
{
	return (v1.x * v2.x + v1.y * v2.y + v1.z * v2.z + v1.w * v2.w);
}

float Vec4::length() const
{
	return std::sqrt(x * x + y * y + z * z + w * w);
}


float Vec4::lengthSquared() const
{
	return (x * x + y * y + z * z + w * w);
}

void Vec4::negate()
{
	x = -x;
	y = -y;
	z = -z;
	w = -w;
}

void Vec4::normalize()
{
	float n = x * x + y * y + z * z + w * w;
	// Already normalized.
	if (n == 1.0f)
		return;

	n = std::sqrt(n);
	// Too close to zero.
	if (n < MATH_TOLERANCE)
		return;

	n = 1.0f / n;
	x *= n;
	y *= n;
	z *= n;
	w *= n;
}

Vec4 Vec4::getNormalized() const
{
	Vec4 v(*this);
	v.normalize();
	return v;
}

void Vec4::scale(float scalar)
{
	x *= scalar;
	y *= scalar;
	z *= scalar;
	w *= scalar;
}

void Vec4::set(float xx, float yy, float zz, float ww)
{
	this->x = xx;
	this->y = yy;
	this->z = zz;
	this->w = ww;
}

void Vec4::set(const float* array)
{
	GP_ASSERT(array);

	x = array[0];
	y = array[1];
	z = array[2];
	w = array[3];
}

void Vec4::set(const Vec4& v)
{
	this->x = v.x;
	this->y = v.y;
	this->z = v.z;
	this->w = v.w;
}

void Vec4::set(const Vec4& p1, const Vec4& p2)
{
	x = p2.x - p1.x;
	y = p2.y - p1.y;
	z = p2.z - p1.z;
	w = p2.w - p1.w;
}

void Vec4::subtract(const Vec4& v)
{
	x -= v.x;
	y -= v.y;
	z -= v.z;
	w -= v.w;
}

void Vec4::subtract(const Vec4& v1, const Vec4& v2, Vec4* dst)
{
	GP_ASSERT(dst);

	dst->x = v1.x - v2.x;
	dst->y = v1.y - v2.y;
	dst->z = v1.z - v2.z;
	dst->w = v1.w - v2.w;
}

const Vec4 Vec4::ZERO = Vec4(0.0f, 0.0f, 0.0f, 0.0f);
const Vec4 Vec4::ONE = Vec4(1.0f, 1.0f, 1.0f, 1.0f);
const Vec4 Vec4::UNIT_X = Vec4(1.0f, 0.0f, 0.0f, 0.0f);
const Vec4 Vec4::UNIT_Y = Vec4(0.0f, 1.0f, 0.0f, 0.0f);
const Vec4 Vec4::UNIT_Z = Vec4(0.0f, 0.0f, 1.0f, 0.0f);
const Vec4 Vec4::UNIT_W = Vec4(0.0f, 0.0f, 0.0f, 1.0f);

 

 

 

 

 

 

标签:const,dst,float,param,Vec4,vector,cocos2d,math
来源: https://blog.51cto.com/u_15273495/2914435