1 /* 2 * Copyright (C) 2014 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.android.camera.ui.motion; 18 19 /** 20 * Simple functions that produce values along a curve for any given input and can compute input 21 * times for a given output value. 22 */ 23 public interface UnitCurve { 24 25 /** 26 * Produce a unit value of this curve at time t. The function should always return a valid 27 * return value for any valid t input. 28 * 29 * @param t ratio of time passed from (0..1) 30 * @return the unit value at t. 31 */ valueAt(float t)32 float valueAt(float t); 33 34 /** 35 * If possible, find a value for t such that valueAt(t) == value or best guess. 36 * 37 * @param value to match to the output of valueAt(t) 38 * @return t where valueAt(t) == value or throw. 39 */ tAt(float value)40 float tAt(float value); 41 } 42