1 /* 2 * Copyright (C) 2013 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except 5 * in compliance with the License. You may obtain a copy of the License at 6 * 7 * http://www.apache.org/licenses/LICENSE-2.0 8 * 9 * Unless required by applicable law or agreed to in writing, software distributed under the License 10 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express 11 * or implied. See the License for the specific language governing permissions and limitations under 12 * the License. 13 */ 14 #include "Vector2D.h" 15 16 #include <math.h> 17 18 Vector2D::Vector2D() : 19 mX(0), mY(0) { 20 } 21 22 Vector2D::Vector2D(float x, float y) : 23 mX(x), mY(y) { 24 } 25 26 Vector2D Vector2D::copy() { 27 Vector2D v(mX, mY); 28 return v; 29 } 30 31 void Vector2D::add(const Vector2D& v) { 32 mX += v.mX; 33 mY += v.mY; 34 } 35 36 void Vector2D::sub(const Vector2D& v) { 37 mX -= v.mX; 38 mY -= v.mY; 39 } 40 41 void Vector2D::scale(float s) { 42 mX *= s; 43 mY *= s; 44 } 45 46 float Vector2D::distance(const Vector2D& v) { 47 float dx = mX - v.mX; 48 float dy = mY - v.mY; 49 return (float) sqrt(dx * dx + dy * dy); 50 } 51 52 void Vector2D::normalize() { 53 float m = magnitude(); 54 if (m > 0) { 55 scale(1 / m); 56 } 57 } 58 59 void Vector2D::limit(float max) { 60 if (magnitude() > max) { 61 normalize(); 62 scale(max); 63 } 64 } 65 66 float Vector2D::magnitude() { 67 return (float) sqrt(mX * mX + mY * mY); 68 } 69
