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
17package com.replica.replicaisland;
18
19import java.util.Arrays;
20
21/**
22 * Describes a single animation for a sprite.
23 */
24public class SpriteAnimation extends PhasedObject {
25    private final static int LINEAR_SEARCH_CUTOFF = 16;
26
27    private FixedSizeArray<AnimationFrame> mFrames;
28    private float[] mFrameStartTimes;
29    private boolean mLoop;
30    private float mLength;
31
32    public SpriteAnimation(int animationId, int frameCount) {
33        super();
34        mFrames = new FixedSizeArray<AnimationFrame>(frameCount);
35        mFrameStartTimes = new float[frameCount];
36        mLoop = false;
37        mLength = 0.0f;
38        setPhase(animationId);
39    }
40
41    public AnimationFrame getFrame(float animationTime) {
42        AnimationFrame result = null;
43        final float length = mLength;
44        if (length > 0.0f) {
45        	final FixedSizeArray<AnimationFrame> frames = mFrames;
46        	assert frames.getCount() == frames.getCapacity();
47            final int frameCount = frames.getCount();
48            result = frames.get(frameCount - 1);
49
50            if (frameCount > 1) {
51	            float currentTime = 0.0f;
52	            float cycleTime = animationTime;
53	            if (mLoop) {
54	                cycleTime = animationTime % length;
55	            }
56
57	            if (cycleTime < length) {
58	            	// When there are very few frames it's actually slower to do a binary search
59	            	// of the frame list.  So we'll use a linear search for small animations
60	            	// and only pull the binary search out when the frame count is large.
61	            	if (mFrameStartTimes.length > LINEAR_SEARCH_CUTOFF) {
62		            	int index = Arrays.binarySearch(mFrameStartTimes, cycleTime);
63		            	if (index < 0) {
64		            		index = -(index + 1) - 1;
65		            	}
66		            	result = frames.get(index);
67	            	} else {
68		                for (int x = 0; x < frameCount; x++) {
69		                    AnimationFrame frame = frames.get(x);
70		                    currentTime += frame.holdTime;
71		                    if (currentTime > cycleTime) {
72		                        result = frame;
73		                        break;
74		                    }
75		                }
76	            	}
77	            }
78	        }
79        }
80        return result;
81    }
82
83    public void addFrame(AnimationFrame frame) {
84    	mFrameStartTimes[mFrames.getCount()] = mLength;
85    	mFrames.add(frame);
86        mLength += frame.holdTime;
87    }
88
89    public float getLength() {
90        return mLength;
91    }
92
93    public void setLoop(boolean loop) {
94        mLoop = loop;
95    }
96
97    public boolean getLoop() {
98        return mLoop;
99    }
100}
101