/*************************************************************************/
/*  vector2.cpp                                                          */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
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/* Copyright (c) 2007-2019 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2019 Godot Engine contributors (cf. AUTHORS.md)    */
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#include "vector2.h"

real_t Vector2::angle() const {

	return Math::atan2(y, x);
}

real_t Vector2::length() const {

	return Math::sqrt(x * x + y * y);
}

real_t Vector2::length_squared() const {

	return x * x + y * y;
}

void Vector2::normalize() {

	real_t l = x * x + y * y;
	if (l != 0) {

		l = Math::sqrt(l);
		x /= l;
		y /= l;
	}
}

Vector2 Vector2::normalized() const {

	Vector2 v = *this;
	v.normalize();
	return v;
}

bool Vector2::is_normalized() const {
	// use length_squared() instead of length() to avoid sqrt(), makes it more stringent.
	return Math::is_equal_approx(length_squared(), 1.0, UNIT_EPSILON);
}

real_t Vector2::distance_to(const Vector2 &p_vector2) const {

	return Math::sqrt((x - p_vector2.x) * (x - p_vector2.x) + (y - p_vector2.y) * (y - p_vector2.y));
}

real_t Vector2::distance_squared_to(const Vector2 &p_vector2) const {

	return (x - p_vector2.x) * (x - p_vector2.x) + (y - p_vector2.y) * (y - p_vector2.y);
}

real_t Vector2::angle_to(const Vector2 &p_vector2) const {

	return Math::atan2(cross(p_vector2), dot(p_vector2));
}

real_t Vector2::angle_to_point(const Vector2 &p_vector2) const {

	return Math::atan2(y - p_vector2.y, x - p_vector2.x);
}

real_t Vector2::dot(const Vector2 &p_other) const {

	return x * p_other.x + y * p_other.y;
}

real_t Vector2::cross(const Vector2 &p_other) const {

	return x * p_other.y - y * p_other.x;
}

Vector2 Vector2::floor() const {

	return Vector2(Math::floor(x), Math::floor(y));
}

Vector2 Vector2::ceil() const {

	return Vector2(Math::ceil(x), Math::ceil(y));
}

Vector2 Vector2::round() const {

	return Vector2(Math::round(x), Math::round(y));
}

Vector2 Vector2::rotated(real_t p_by) const {

	Vector2 v;
	v.set_rotation(angle() + p_by);
	v *= length();
	return v;
}

Vector2 Vector2::project(const Vector2 &p_b) const {
	return p_b * (dot(p_b) / p_b.length_squared());
}

Vector2 Vector2::snapped(const Vector2 &p_by) const {

	return Vector2(
			Math::stepify(x, p_by.x),
			Math::stepify(y, p_by.y));
}

Vector2 Vector2::clamped(real_t p_len) const {

	real_t l = length();
	Vector2 v = *this;
	if (l > 0 && p_len < l) {

		v /= l;
		v *= p_len;
	}

	return v;
}

Vector2 Vector2::cubic_interpolate(const Vector2 &p_b, const Vector2 &p_pre_a, const Vector2 &p_post_b, real_t p_t) const {

	Vector2 p0 = p_pre_a;
	Vector2 p1 = *this;
	Vector2 p2 = p_b;
	Vector2 p3 = p_post_b;

	real_t t = p_t;
	real_t t2 = t * t;
	real_t t3 = t2 * t;

	Vector2 out;
	out = 0.5 * ((p1 * 2.0) +
						(-p0 + p2) * t +
						(2.0 * p0 - 5.0 * p1 + 4 * p2 - p3) * t2 +
						(-p0 + 3.0 * p1 - 3.0 * p2 + p3) * t3);
	return out;
}

// slide returns the component of the vector along the given plane, specified by its normal vector.
Vector2 Vector2::slide(const Vector2 &p_normal) const {
#ifdef MATH_CHECKS
	ERR_FAIL_COND_V(!p_normal.is_normalized(), Vector2());
#endif
	return *this - p_normal * this->dot(p_normal);
}

Vector2 Vector2::bounce(const Vector2 &p_normal) const {
	return -reflect(p_normal);
}

Vector2 Vector2::reflect(const Vector2 &p_normal) const {
#ifdef MATH_CHECKS
	ERR_FAIL_COND_V(!p_normal.is_normalized(), Vector2());
#endif
	return 2.0 * p_normal * this->dot(p_normal) - *this;
}

/* Vector2i */

Vector2i Vector2i::operator+(const Vector2i &p_v) const {

	return Vector2i(x + p_v.x, y + p_v.y);
}
void Vector2i::operator+=(const Vector2i &p_v) {

	x += p_v.x;
	y += p_v.y;
}
Vector2i Vector2i::operator-(const Vector2i &p_v) const {

	return Vector2i(x - p_v.x, y - p_v.y);
}
void Vector2i::operator-=(const Vector2i &p_v) {

	x -= p_v.x;
	y -= p_v.y;
}

Vector2i Vector2i::operator*(const Vector2i &p_v1) const {

	return Vector2i(x * p_v1.x, y * p_v1.y);
};

Vector2i Vector2i::operator*(const int &rvalue) const {

	return Vector2i(x * rvalue, y * rvalue);
};
void Vector2i::operator*=(const int &rvalue) {

	x *= rvalue;
	y *= rvalue;
};

Vector2i Vector2i::operator/(const Vector2i &p_v1) const {

	return Vector2i(x / p_v1.x, y / p_v1.y);
};

Vector2i Vector2i::operator/(const int &rvalue) const {

	return Vector2i(x / rvalue, y / rvalue);
};

void Vector2i::operator/=(const int &rvalue) {

	x /= rvalue;
	y /= rvalue;
};

Vector2i Vector2i::operator-() const {

	return Vector2i(-x, -y);
}

bool Vector2i::operator==(const Vector2i &p_vec2) const {

	return x == p_vec2.x && y == p_vec2.y;
}
bool Vector2i::operator!=(const Vector2i &p_vec2) const {

	return x != p_vec2.x || y != p_vec2.y;
}