[Core] Move Vector2 to its own file

Makes 2D math code easier to read and makes Vector2 consistent with Vector3. In the future, we may move other things out of math_2d as well.

1 files changed, 187 insertions, 0 deletions

diff --git a/core/math/vector2.cpp b/core/math/vector2.cpp
new file mode 100644
index 0000000000..8e59ddbd07
--- /dev/null
+++ b/core/math/vector2.cpp
@@ -0,0 +1,187 @@
+/*************************************************************************/
+/*  vector2.cpp                                                          */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2018 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2018 Godot Engine contributors (cf. AUTHORS.md)    */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#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);
+}
+
+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_vec) const {
+
+	Vector2 v1 = p_vec;
+	Vector2 v2 = *this;
+	return v2 * (v1.dot(v2) / v2.dot(v2));
+}
+
+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() == false, 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() == false, Vector2());
+#endif
+	return 2.0 * p_normal * this->dot(p_normal) - *this;
+}