1cfd74d65d832137e20e193c960802afba73b5d38sm/* 23c1e67e433728684b5f228c5d4f3e5b1457bb271sm * Copyright (C) 2010 The Android Open Source Project 3cfd74d65d832137e20e193c960802afba73b5d38sm * 4cfd74d65d832137e20e193c960802afba73b5d38sm * Licensed under the Apache License, Version 2.0 (the "License"); 5cfd74d65d832137e20e193c960802afba73b5d38sm * you may not use this file except in compliance with the License. 6cfd74d65d832137e20e193c960802afba73b5d38sm * You may obtain a copy of the License at 7cfd74d65d832137e20e193c960802afba73b5d38sm * 8cfd74d65d832137e20e193c960802afba73b5d38sm * http://www.apache.org/licenses/LICENSE-2.0 9cfd74d65d832137e20e193c960802afba73b5d38sm * 10cfd74d65d832137e20e193c960802afba73b5d38sm * Unless required by applicable law or agreed to in writing, software 11cfd74d65d832137e20e193c960802afba73b5d38sm * distributed under the License is distributed on an "AS IS" BASIS, 12cfd74d65d832137e20e193c960802afba73b5d38sm * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13cfd74d65d832137e20e193c960802afba73b5d38sm * See the License for the specific language governing permissions and 14cfd74d65d832137e20e193c960802afba73b5d38sm * limitations under the License. 15cfd74d65d832137e20e193c960802afba73b5d38sm */ 16cfd74d65d832137e20e193c960802afba73b5d38sm 17cfd74d65d832137e20e193c960802afba73b5d38smpackage com.replica.replicaisland; 18cfd74d65d832137e20e193c960802afba73b5d38sm 19cfd74d65d832137e20e193c960802afba73b5d38sm/** A collection of miscellaneous utility functions. */ 20cfd74d65d832137e20e193c960802afba73b5d38smpublic class Utils { 21cfd74d65d832137e20e193c960802afba73b5d38sm private static final float EPSILON = 0.0001f; 22cfd74d65d832137e20e193c960802afba73b5d38sm 23cfd74d65d832137e20e193c960802afba73b5d38sm public final static boolean close(float a, float b) { 24cfd74d65d832137e20e193c960802afba73b5d38sm return close(a, b, EPSILON); 25cfd74d65d832137e20e193c960802afba73b5d38sm } 26cfd74d65d832137e20e193c960802afba73b5d38sm 27cfd74d65d832137e20e193c960802afba73b5d38sm public final static boolean close(float a, float b, float epsilon) { 28cfd74d65d832137e20e193c960802afba73b5d38sm return Math.abs(a - b) < epsilon; 29cfd74d65d832137e20e193c960802afba73b5d38sm } 30cfd74d65d832137e20e193c960802afba73b5d38sm 31cfd74d65d832137e20e193c960802afba73b5d38sm public final static int sign(float a) { 32cfd74d65d832137e20e193c960802afba73b5d38sm if (a >= 0.0f) { 33cfd74d65d832137e20e193c960802afba73b5d38sm return 1; 34cfd74d65d832137e20e193c960802afba73b5d38sm } else { 35cfd74d65d832137e20e193c960802afba73b5d38sm return -1; 36cfd74d65d832137e20e193c960802afba73b5d38sm } 37cfd74d65d832137e20e193c960802afba73b5d38sm } 38cfd74d65d832137e20e193c960802afba73b5d38sm 39cfd74d65d832137e20e193c960802afba73b5d38sm public final static int clamp(int value, int min, int max) { 40cfd74d65d832137e20e193c960802afba73b5d38sm int result = value; 41cfd74d65d832137e20e193c960802afba73b5d38sm if (min == max) { 42cfd74d65d832137e20e193c960802afba73b5d38sm if (value != min) { 43cfd74d65d832137e20e193c960802afba73b5d38sm result = min; 44cfd74d65d832137e20e193c960802afba73b5d38sm } 45cfd74d65d832137e20e193c960802afba73b5d38sm } else if (min < max) { 46cfd74d65d832137e20e193c960802afba73b5d38sm if (value < min) { 47cfd74d65d832137e20e193c960802afba73b5d38sm result = min; 48cfd74d65d832137e20e193c960802afba73b5d38sm } else if (value > max) { 49cfd74d65d832137e20e193c960802afba73b5d38sm result = max; 50cfd74d65d832137e20e193c960802afba73b5d38sm } 51cfd74d65d832137e20e193c960802afba73b5d38sm } else { 52cfd74d65d832137e20e193c960802afba73b5d38sm result = clamp(value, max, min); 53cfd74d65d832137e20e193c960802afba73b5d38sm } 54cfd74d65d832137e20e193c960802afba73b5d38sm 55cfd74d65d832137e20e193c960802afba73b5d38sm return result; 56cfd74d65d832137e20e193c960802afba73b5d38sm } 579d4cc2572d37983607df38b0f4216ed76ac51814sm 58cfd74d65d832137e20e193c960802afba73b5d38sm 59cfd74d65d832137e20e193c960802afba73b5d38sm public final static int byteArrayToInt(byte[] b) { 60cfd74d65d832137e20e193c960802afba73b5d38sm if (b.length != 4) { 61cfd74d65d832137e20e193c960802afba73b5d38sm return 0; 62cfd74d65d832137e20e193c960802afba73b5d38sm } 63cfd74d65d832137e20e193c960802afba73b5d38sm 64cfd74d65d832137e20e193c960802afba73b5d38sm // Same as DataInputStream's 'readInt' method 65cfd74d65d832137e20e193c960802afba73b5d38sm /*int i = (((b[0] & 0xff) << 24) | ((b[1] & 0xff) << 16) | ((b[2] & 0xff) << 8) 66cfd74d65d832137e20e193c960802afba73b5d38sm | (b[3] & 0xff));*/ 67cfd74d65d832137e20e193c960802afba73b5d38sm 68cfd74d65d832137e20e193c960802afba73b5d38sm // little endian 69cfd74d65d832137e20e193c960802afba73b5d38sm int i = (((b[3] & 0xff) << 24) | ((b[2] & 0xff) << 16) | ((b[1] & 0xff) << 8) 70cfd74d65d832137e20e193c960802afba73b5d38sm | (b[0] & 0xff)); 71cfd74d65d832137e20e193c960802afba73b5d38sm 72cfd74d65d832137e20e193c960802afba73b5d38sm return i; 73cfd74d65d832137e20e193c960802afba73b5d38sm } 74cfd74d65d832137e20e193c960802afba73b5d38sm 75cfd74d65d832137e20e193c960802afba73b5d38sm public final static float byteArrayToFloat(byte[] b) { 76cfd74d65d832137e20e193c960802afba73b5d38sm 77cfd74d65d832137e20e193c960802afba73b5d38sm // intBitsToFloat() converts bits as follows: 78cfd74d65d832137e20e193c960802afba73b5d38sm /* 79cfd74d65d832137e20e193c960802afba73b5d38sm int s = ((i >> 31) == 0) ? 1 : -1; 80cfd74d65d832137e20e193c960802afba73b5d38sm int e = ((i >> 23) & 0xff); 81cfd74d65d832137e20e193c960802afba73b5d38sm int m = (e == 0) ? (i & 0x7fffff) << 1 : (i & 0x7fffff) | 0x800000; 82cfd74d65d832137e20e193c960802afba73b5d38sm */ 83cfd74d65d832137e20e193c960802afba73b5d38sm 84cfd74d65d832137e20e193c960802afba73b5d38sm return Float.intBitsToFloat(byteArrayToInt(b)); 85cfd74d65d832137e20e193c960802afba73b5d38sm } 86cfd74d65d832137e20e193c960802afba73b5d38sm 87cfd74d65d832137e20e193c960802afba73b5d38sm public final static float framesToTime(int framesPerSecond, int frameCount) { 88cfd74d65d832137e20e193c960802afba73b5d38sm return (1.0f / framesPerSecond) * frameCount; 89cfd74d65d832137e20e193c960802afba73b5d38sm } 90cfd74d65d832137e20e193c960802afba73b5d38sm 91cfd74d65d832137e20e193c960802afba73b5d38sm} 92