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axmol/cocos/math/Vector2.cpp

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#include "Vector2.h"
#include "2d/ccMacros.h"
#include "MathUtil.h"
NS_CC_MATH_BEGIN
// returns true if segment A-B intersects with segment C-D. S->E is the ovderlap part
bool isOneDimensionSegmentOverlap(float A, float B, float C, float D, float *S, float * E)
{
float ABmin = MIN(A, B);
float ABmax = MAX(A, B);
float CDmin = MIN(C, D);
float CDmax = MAX(C, D);
if (ABmax < CDmin || CDmax < ABmin)
{
// ABmin->ABmax->CDmin->CDmax or CDmin->CDmax->ABmin->ABmax
return false;
}
else
{
if (ABmin >= CDmin && ABmin <= CDmax)
{
// CDmin->ABmin->CDmax->ABmax or CDmin->ABmin->ABmax->CDmax
if (S != nullptr) *S = ABmin;
if (E != nullptr) *E = CDmax < ABmax ? CDmax : ABmax;
}
else if (ABmax >= CDmin && ABmax <= CDmax)
{
// ABmin->CDmin->ABmax->CDmax
if (S != nullptr) *S = CDmin;
if (E != nullptr) *E = ABmax;
}
else
{
// ABmin->CDmin->CDmax->ABmax
if (S != nullptr) *S = CDmin;
if (E != nullptr) *E = CDmax;
}
return true;
}
}
// cross procuct of 2 vector. A->B X C->D
float crossProduct2Vector(const Vector2& A, const Vector2& B, const Vector2& C, const Vector2& D)
{
return (D.y - C.y) * (B.x - A.x) - (D.x - C.x) * (B.y - A.y);
}
Vector2::Vector2()
: x(0.0f), y(0.0f)
{
}
Vector2::Vector2(float xx, float yy)
: x(xx), y(yy)
{
}
Vector2::Vector2(const float* array)
{
set(array);
}
Vector2::Vector2(const Vector2& p1, const Vector2& p2)
{
set(p1, p2);
}
Vector2::Vector2(const Vector2& copy)
{
set(copy);
}
Vector2::~Vector2()
{
}
const Vector2& Vector2::zero()
{
static Vector2 value(0.0f, 0.0f);
return value;
}
const Vector2& Vector2::one()
{
static Vector2 value(1.0f, 1.0f);
return value;
}
const Vector2& Vector2::unitX()
{
static Vector2 value(1.0f, 0.0f);
return value;
}
const Vector2& Vector2::unitY()
{
static Vector2 value(0.0f, 1.0f);
return value;
}
bool Vector2::isZero() const
{
return x == 0.0f && y == 0.0f;
}
bool Vector2::isOne() const
{
return x == 1.0f && y == 1.0f;
}
float Vector2::angle(const Vector2& v1, const Vector2& v2)
{
float dz = v1.x * v2.y - v1.y * v2.x;
return atan2f(fabsf(dz) + MATH_FLOAT_SMALL, dot(v1, v2));
}
void Vector2::add(const Vector2& v)
{
x += v.x;
y += v.y;
}
void Vector2::add(const Vector2& v1, const Vector2& v2, Vector2* dst)
{
GP_ASSERT(dst);
dst->x = v1.x + v2.x;
dst->y = v1.y + v2.y;
}
void Vector2::clamp(const Vector2& min, const Vector2& max)
{
GP_ASSERT(!(min.x > max.x || min.y > max.y ));
// 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;
}
void Vector2::clamp(const Vector2& v, const Vector2& min, const Vector2& max, Vector2* dst)
{
GP_ASSERT(dst);
GP_ASSERT(!(min.x > max.x || min.y > max.y ));
// 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;
}
float Vector2::distance(const Vector2& v) const
{
float dx = v.x - x;
float dy = v.y - y;
return sqrt(dx * dx + dy * dy);
}
float Vector2::distanceSquared(const Vector2& v) const
{
float dx = v.x - x;
float dy = v.y - y;
return (dx * dx + dy * dy);
}
float Vector2::dot(const Vector2& v) const
{
return (x * v.x + y * v.y);
}
float Vector2::dot(const Vector2& v1, const Vector2& v2)
{
return (v1.x * v2.x + v1.y * v2.y);
}
float Vector2::length() const
{
return sqrt(x * x + y * y);
}
float Vector2::lengthSquared() const
{
return (x * x + y * y);
}
void Vector2::negate()
{
x = -x;
y = -y;
}
Vector2& Vector2::normalize()
{
normalize(this);
return *this;
}
void Vector2::normalize(Vector2* dst) const
{
GP_ASSERT(dst);
if (dst != this)
{
dst->x = x;
dst->y = y;
}
float n = x * x + y * y;
// Already normalized.
if (n == 1.0f)
return;
n = sqrt(n);
// Too close to zero.
if (n < MATH_TOLERANCE)
return;
n = 1.0f / n;
dst->x *= n;
dst->y *= n;
}
void Vector2::scale(float scalar)
{
x *= scalar;
y *= scalar;
}
void Vector2::scale(const Vector2& scale)
{
x *= scale.x;
y *= scale.y;
}
void Vector2::rotate(const Vector2& point, float angle)
{
double sinAngle = sin(angle);
double cosAngle = cos(angle);
if (point.isZero())
{
float tempX = x * cosAngle - y * sinAngle;
y = y * cosAngle + x * sinAngle;
x = tempX;
}
else
{
float tempX = x - point.x;
float tempY = y - point.y;
x = tempX * cosAngle - tempY * sinAngle + point.x;
y = tempY * cosAngle + tempX * sinAngle + point.y;
}
}
void Vector2::set(float xx, float yy)
{
this->x = xx;
this->y = yy;
}
void Vector2::set(const float* array)
{
GP_ASSERT(array);
x = array[0];
y = array[1];
}
void Vector2::set(const Vector2& v)
{
this->x = v.x;
this->y = v.y;
}
void Vector2::set(const Vector2& p1, const Vector2& p2)
{
x = p2.x - p1.x;
y = p2.y - p1.y;
}
void Vector2::subtract(const Vector2& v)
{
x -= v.x;
y -= v.y;
}
void Vector2::subtract(const Vector2& v1, const Vector2& v2, Vector2* dst)
{
GP_ASSERT(dst);
dst->x = v1.x - v2.x;
dst->y = v1.y - v2.y;
}
void Vector2::smooth(const Vector2& target, float elapsedTime, float responseTime)
{
if (elapsedTime > 0)
{
*this += (target - *this) * (elapsedTime / (elapsedTime + responseTime));
}
}
void Vector2::setPoint(float xx, float yy)
{
this->x = xx;
this->y = yy;
}
bool Vector2::equals(const Vector2& target) const
{
return (fabs(this->x - target.x) < FLT_EPSILON)
&& (fabs(this->y - target.y) < FLT_EPSILON);
}
bool Vector2::fuzzyEquals(const Vector2& b, float var) const
{
if(x - var <= b.x && b.x <= x + var)
if(y - var <= b.y && b.y <= y + var)
return true;
return false;
}
float Vector2::getAngle(const Vector2& other) const
{
Vector2 a2 = normalize();
Vector2 b2 = other.normalize();
float angle = atan2f(a2.cross(b2), a2.dot(b2));
if( fabs(angle) < FLT_EPSILON ) return 0.f;
return angle;
}
Vector2 Vector2::rotateByAngle(const Vector2& pivot, float angle) const
{
return pivot + (*this - pivot).rotate(Vector2::forAngle(angle));
}
bool Vector2::isLineIntersect(const Vector2& A, const Vector2& B,
const Vector2& C, const Vector2& D,
float *S, float *T)
{
// FAIL: Line undefined
if ( (A.x==B.x && A.y==B.y) || (C.x==D.x && C.y==D.y) )
{
return false;
}
const float denom = crossProduct2Vector(A, B, C, D);
if (denom == 0)
{
// Lines parallel or overlap
return false;
}
if (S != nullptr) *S = crossProduct2Vector(C, D, C, A) / denom;
if (T != nullptr) *T = crossProduct2Vector(A, B, C, A) / denom;
return true;
}
bool Vector2::isLineParallel(const Vector2& A, const Vector2& B,
const Vector2& C, const Vector2& D)
{
// FAIL: Line undefined
if ( (A.x==B.x && A.y==B.y) || (C.x==D.x && C.y==D.y) )
{
return false;
}
if (crossProduct2Vector(A, B, C, D) == 0)
{
// line overlap
if (crossProduct2Vector(C, D, C, A) == 0 || crossProduct2Vector(A, B, C, A) == 0)
{
return false;
}
return true;
}
return false;
}
bool Vector2::isLineOverlap(const Vector2& A, const Vector2& B,
const Vector2& C, const Vector2& D)
{
// FAIL: Line undefined
if ( (A.x==B.x && A.y==B.y) || (C.x==D.x && C.y==D.y) )
{
return false;
}
if (crossProduct2Vector(A, B, C, D) == 0 &&
(crossProduct2Vector(C, D, C, A) == 0 || crossProduct2Vector(A, B, C, A) == 0))
{
return true;
}
return false;
}
bool Vector2::isSegmentOverlap(const Vector2& A, const Vector2& B, const Vector2& C, const Vector2& D, Vector2* S, Vector2* E)
{
if (isLineOverlap(A, B, C, D))
{
return isOneDimensionSegmentOverlap(A.x, B.x, C.x, D.x, &S->x, &E->x) &&
isOneDimensionSegmentOverlap(A.y, B.y, C.y, D.y, &S->y, &E->y);
}
return false;
}
bool Vector2::isSegmentIntersect(const Vector2& A, const Vector2& B, const Vector2& C, const Vector2& D)
{
float S, T;
if (isLineIntersect(A, B, C, D, &S, &T )&&
(S >= 0.0f && S <= 1.0f && T >= 0.0f && T <= 1.0f))
{
return true;
}
return false;
}
Vector2 Vector2::getIntersectPoint(const Vector2& A, const Vector2& B, const Vector2& C, const Vector2& D)
{
float S, T;
if (isLineIntersect(A, B, C, D, &S, &T))
{
// Vector2 of intersection
Vector2 P;
P.x = A.x + S * (B.x - A.x);
P.y = A.y + S * (B.y - A.y);
return P;
}
return Vector2::ZERO;
}
const Vector2 Vector2::ZERO = Vector2(0.0f, 0.0f);
const Vector2 Vector2::ANCHOR_MIDDLE = Vector2(0.5f, 0.5f);
const Vector2 Vector2::ANCHOR_BOTTOM_LEFT = Vector2(0.0f, 0.0f);
const Vector2 Vector2::ANCHOR_TOP_LEFT = Vector2(0.0f, 1.0f);
const Vector2 Vector2::ANCHOR_BOTTOM_RIGHT = Vector2(1.0f, 0.0f);
const Vector2 Vector2::ANCHOR_TOP_RIGHT = Vector2(1.0f, 1.0f);
const Vector2 Vector2::ANCHOR_MIDDLE_RIGHT = Vector2(1.0f, 0.5f);
const Vector2 Vector2::ANCHOR_MIDDLE_LEFT = Vector2(0.0f, 0.5f);
const Vector2 Vector2::ANCHOR_MIDDLE_TOP = Vector2(0.5f, 1.0f);
const Vector2 Vector2::ANCHOR_MIDDLE_BOTTOM = Vector2(0.5f, 0.0f);
NS_CC_MATH_END
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