1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.replica.replicaisland; 18 19 /** 20 * Simple 2D vector class. Handles basic vector math for 2D vectors. 21 */ 22 public final class Vector2 extends AllocationGuard { 23 public float x; 24 public float y; 25 26 public static final Vector2 ZERO = new Vector2(0, 0); 27 Vector2()28 public Vector2() { 29 super(); 30 } 31 Vector2(float xValue, float yValue)32 public Vector2(float xValue, float yValue) { 33 set(xValue, yValue); 34 } 35 Vector2(Vector2 other)36 public Vector2(Vector2 other) { 37 set(other); 38 } 39 add(Vector2 other)40 public final void add(Vector2 other) { 41 x += other.x; 42 y += other.y; 43 } 44 add(float otherX, float otherY)45 public final void add(float otherX, float otherY) { 46 x += otherX; 47 y += otherY; 48 } 49 subtract(Vector2 other)50 public final void subtract(Vector2 other) { 51 x -= other.x; 52 y -= other.y; 53 } 54 multiply(float magnitude)55 public final void multiply(float magnitude) { 56 x *= magnitude; 57 y *= magnitude; 58 } 59 multiply(Vector2 other)60 public final void multiply(Vector2 other) { 61 x *= other.x; 62 y *= other.y; 63 } 64 divide(float magnitude)65 public final void divide(float magnitude) { 66 if (magnitude != 0.0f) { 67 x /= magnitude; 68 y /= magnitude; 69 } 70 } 71 set(Vector2 other)72 public final void set(Vector2 other) { 73 x = other.x; 74 y = other.y; 75 } 76 set(float xValue, float yValue)77 public final void set(float xValue, float yValue) { 78 x = xValue; 79 y = yValue; 80 } 81 dot(Vector2 other)82 public final float dot(Vector2 other) { 83 return (x * other.x) + (y * other.y); 84 } 85 length()86 public final float length() { 87 return (float) Math.sqrt(length2()); 88 } 89 length2()90 public final float length2() { 91 return (x * x) + (y * y); 92 } 93 distance2(Vector2 other)94 public final float distance2(Vector2 other) { 95 float dx = x - other.x; 96 float dy = y - other.y; 97 return (dx * dx) + (dy * dy); 98 } 99 normalize()100 public final float normalize() { 101 final float magnitude = length(); 102 103 // TODO: I'm choosing safety over speed here. 104 if (magnitude != 0.0f) { 105 x /= magnitude; 106 y /= magnitude; 107 } 108 109 return magnitude; 110 } 111 zero()112 public final void zero() { 113 set(0.0f, 0.0f); 114 } 115 flipHorizontal(float aboutWidth)116 public final void flipHorizontal(float aboutWidth) { 117 x = (aboutWidth - x); 118 } 119 flipVertical(float aboutHeight)120 public final void flipVertical(float aboutHeight) { 121 y = (aboutHeight - y); 122 } 123 } 124