[Unity] 里使用Gif图片

参考http://wiki.unity3d.com/index.php/AnimatedGifDrawer。

原理是：将gif图拆分成多个单个图片，用Texture2D存放，然后逐个替换Texture2D达到动态效果。

 

/** 
 *FileName:     gifTest 
 *Author:       #AUTHOR# 
 *Description:    
*/
using System.Drawing;
using System.Drawing.Imaging;
using UnityEngine;
using System.Collections;
using System.Collections.Generic;
using System;

public class GifPlay : MonoBehaviour
{
    public float speed = 1;

    private string loadingGifPath;
    private Vector2 drawPosition;
    private UnityEngine.UI.RawImage raw;
    private List gifFrames = new List();

    void Awake()
    {
        raw = GetComponent();

        loadingGifPath = Application.streamingAssetsPath + "/gif.gif";
        drawPosition = transform.position;
        var gifImage = Image.FromFile(loadingGifPath);
        var dimension = new FrameDimension(gifImage.FrameDimensionsList[0]);
        int frameCount = gifImage.GetFrameCount(dimension);
        for (int i = 0; i < frameCount; i++)
        {
            gifImage.SelectActiveFrame(dimension, i);
            var frame = new Bitmap(gifImage.Width, gifImage.Height);
            System.Drawing.Graphics.FromImage(frame).DrawImage(gifImage, Point.Empty);
            var frameTexture = new Texture2D(frame.Width, frame.Height);
            for (int x = 0; x < frame.Width; x++)
                for (int y = 0; y < frame.Height; y++)
                {
                    System.Drawing.Color sourceColor = frame.GetPixel(x, y);
                    frameTexture.SetPixel(frame.Width - 1 - x, y, new Color32(sourceColor.R, sourceColor.G, sourceColor.B, sourceColor.A)); // for some reason, x is flipped
                }
            frameTexture.Apply();
            gifFrames.Add(frameTexture);
        }
    }

    public IEnumerator PlayGif() {
        for (int i = 0; i < gifFrames.Count; i++)
        {
            raw.texture = gifFrames[i];
            yield return 0;
        }
    }

    private void Update()
    {
        if (Input.GetKeyDown(KeyCode.P))
        {
            //播放一次
            StartCoroutine(PlayGif());
        }
        //循环播放
        gifFrames[(int)(Time.frameCount * speed) % gifFrames.Count]);
    }

    //void OnGUI()
    //{
    //    //GUI.DrawTexture(new Rect(drawPosition.x, drawPosition.y, gifFrames[0].width, gifFrames[0].height), gifFrames[(int)(Time.frameCount * speed) % gifFrames.Count]);
    //}
}