2 * Copyright (C) 2012 The Android Open Source Project
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
17 package com.android.gallery3d.ui;
19 import android.view.animation.AccelerateDecelerateInterpolator;
20 import android.view.animation.AccelerateInterpolator;
21 import android.view.animation.DecelerateInterpolator;
22 import android.view.animation.Interpolator;
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;
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();
37 // Calculate the slide factor based on the give time fraction.
38 public static float calculateSlide(float fraction) {
39 return sSlideInterpolator.getInterpolation(fraction);
42 // Calculate the scale factor based on the given time fraction.
43 public static float calculateScale(float fraction) {
45 if (fraction <= 0.5f) {
46 // Zoom in for the beginning.
47 value = 1f - ZOOM_DELTA *
48 sZoomOutInterpolator.getInterpolation(fraction * 2);
50 // Zoom out for the ending.
51 value = ZOOM_IN_BEGIN + ZOOM_DELTA *
52 sZoomInInterpolator.getInterpolation((fraction - 0.5f) * 2f);