1 /* 2 * Copyright (C) 2012 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.gallery3d.ui; 18 19 import android.view.animation.AccelerateDecelerateInterpolator; 20 import android.view.animation.AccelerateInterpolator; 21 import android.view.animation.DecelerateInterpolator; 22 import android.view.animation.Interpolator; 23 24 public class CaptureAnimation { 25 // The amount of change for zooming out. 26 private static final float ZOOM_DELTA = 0.2f; 27 // Pre-calculated value for convenience. 28 private static final float ZOOM_IN_BEGIN = 1f - ZOOM_DELTA; 29 30 private static final Interpolator sZoomOutInterpolator = 31 new DecelerateInterpolator(); 32 private static final Interpolator sZoomInInterpolator = 33 new AccelerateInterpolator(); 34 private static final Interpolator sSlideInterpolator = 35 new AccelerateDecelerateInterpolator(); 36 37 // Calculate the slide factor based on the give time fraction. 38 public static float calculateSlide(float fraction) { 39 return sSlideInterpolator.getInterpolation(fraction); 40 } 41 42 // Calculate the scale factor based on the given time fraction. 43 public static float calculateScale(float fraction) { 44 float value; 45 if (fraction <= 0.5f) { 46 // Zoom in for the beginning. 47 value = 1f - ZOOM_DELTA * 48 sZoomOutInterpolator.getInterpolation(fraction * 2); 49 } else { 50 // Zoom out for the ending. 51 value = ZOOM_IN_BEGIN + ZOOM_DELTA * 52 sZoomInInterpolator.getInterpolation((fraction - 0.5f) * 2f); 53 } 54 return value; 55 } 56 } 57
