Unity-WIKI 之 AnimationToPNG

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*/

// AnimationToPNG is based on Twinfox and bitbutter's Render Particle to Animated Texture Scripts, 
// this script will render out an animation that is played when "Play" is pressed in the editor.

/* 
Basically this is a script you can attach to any gameobject in the scene. 

If you have Unity Pro, you can use Render Textures, which can accurately 
render the transparent background for your animations easily in full resolution 
of the camera. The script will autodetect if you have Unity Pro and use 
Render Textures automatically. 

If you are using Unity Free, then the screen will have a split area using 
half of the screen width to render the animations. 

You can change the "animationName" to a string of your choice for a 
prefix for the output file names, if it is left empty then no filename 
will be added. 

The destination folder is relative to the Project Folder root, so you 
can change the string to a folder name of your choice and it will be 
created. If it already exists, it will simply create a new folder with a 
number incremented as to how many of those named folders exist. 

Choose how many frames per second the animation will run by changing the 
"frameRate" variable, and how many frames of the animation you wish to 
capture by changing the "framesToCapture" variable. 

Once "Play" is pressed in the Unity Editor, it should output all the 
animation frames to PNGs output in the folder you have chosen, and will 
stop capturing after the number of frames you wish to capture is 
completed. 
*/

public class AnimationToPNG : MonoBehaviour
{

    // Animation Name to be the prefix for the output filenames
    public string animationName = "";

    // Default folder name where you want the animations to be output
    public string folder = "PNG_Animations";

    // Framerate at which you want to play the animation
    public int frameRate = 25;

    // How many frames you want to capture during the animation
    public int framesToCapture = 25;

    // White Camera
    private Camera whiteCam;

    // Black Camera
    private Camera blackCam;

    // Pixels to World Unit size
    public float pixelsToWorldUnit = 74.48275862068966f;

    // If you have Unity Pro you can use a RenderTexture which will render the full camera width, otherwise it will only render half
    private bool useRenderTexture = false;

    private int videoframe = 0; // how many frames we've rendered

    private float originaltimescaleTime; // track the original time scale so we can freeze the animation between frames

    private string realFolder = ""; // real folder where the output files will be

    private bool done = false; // is the capturing finished?

    private bool readyToCapture = false;  // Make sure all the camera setup is complete before capturing

    private float cameraSize; // Size of the orthographic camera established from the current screen resolution and the pixels to world unit

    private Texture2D texb; // black camera texture

    private Texture2D texw; // white camera texture

    private Texture2D outputtex; // final output texture

    private RenderTexture blackCamRenderTexture; // black camera render texure

    private RenderTexture whiteCamRenderTexture; // white camera render texure

    public void Start()
    {
        useRenderTexture = Application.HasProLicense();

        // Set the playback framerate!
        // (real time doesn't influence time anymore)
        Time.captureFramerate = frameRate;

        // Create a folder that doesn't exist yet. Append number if necessary.
        realFolder = folder;
        int count = 1;
        while (Directory.Exists(realFolder))
        {
            realFolder = folder + count;
            count++;
        }
        // Create the folder
        Directory.CreateDirectory(realFolder);

        originaltimescaleTime = Time.timeScale;

        // Force orthographic camera to render out sprites per pixel size designated by pixels to world unit
        cameraSize = Screen.width / (((Screen.width / Screen.height) * 2) * pixelsToWorldUnit);

        GameObject bc = new GameObject("Black Camera");
        bc.transform.localPosition = new Vector3(0, 0, -1);
        blackCam = bc.AddComponent<Camera>();
        blackCam.backgroundColor = Color.black;
        blackCam.orthographic = true;
        blackCam.orthographicSize = cameraSize;
        blackCam.tag = "MainCamera";

        GameObject wc = new GameObject("White Camera");
        wc.transform.localPosition = new Vector3(0, 0, -1);
        whiteCam = wc.AddComponent<Camera>();
        whiteCam.backgroundColor = Color.white;
        whiteCam.orthographic = true;
        whiteCam.orthographicSize = cameraSize;

        // If not using a Render Texture then set the cameras to split the screen to ensure we have an accurate image with alpha
        if (!useRenderTexture)
        {
            // Change the camera rects to have split on screen to capture the animation properly
            blackCam.rect = new Rect(0.0f, 0.0f, 0.5f, 1.0f);

            whiteCam.rect = new Rect(0.5f, 0.0f, 0.5f, 1.0f);
        }
        // Cameras are set ready to capture!
        readyToCapture = true;
    }

    void Update()
    {
        // If the capturing is not done and the cameras are set, then Capture the animation
        if (!done && readyToCapture)
        {
            StartCoroutine(Capture());
        }
    }

    void LateUpdate()
    {
        // When we are all done capturing, clean up all the textures and RenderTextures from the scene
        if (done)
        {
            DestroyImmediate(texb);
            DestroyImmediate(texw);
            DestroyImmediate(outputtex);

            if (useRenderTexture)
            {
                //Clean Up
                whiteCam.targetTexture = null;
                RenderTexture.active = null;
                DestroyImmediate(whiteCamRenderTexture);

                blackCam.targetTexture = null;
                RenderTexture.active = null;
                DestroyImmediate(blackCamRenderTexture);
            }
        }
    }

    IEnumerator Capture()
    {
        if (videoframe < framesToCapture)
        {
            // name is "realFolder/animationName0000.png"
            // string name = realFolder + "/" + animationName + Time.frameCount.ToString("0000") + ".png";
            string filename = String.Format("{0}/" + animationName + "{1:D04}.png", realFolder, Time.frameCount);

            // Stop time
            Time.timeScale = 0;
            // Yield to next frame and then start the rendering
            yield return new WaitForEndOfFrame();

            // If we are using a render texture to make the animation frames then set up the camera render textures
            if (useRenderTexture)
            {
                //Initialize and render textures
                blackCamRenderTexture = new RenderTexture(Screen.width, Screen.height, 24, RenderTextureFormat.ARGB32);
                whiteCamRenderTexture = new RenderTexture(Screen.width, Screen.height, 24, RenderTextureFormat.ARGB32);

                blackCam.targetTexture = blackCamRenderTexture;
                blackCam.Render();
                RenderTexture.active = blackCamRenderTexture;
                texb = GetTex2D(true);

                //Now do it for Alpha Camera
                whiteCam.targetTexture = whiteCamRenderTexture;
                whiteCam.Render();
                RenderTexture.active = whiteCamRenderTexture;
                texw = GetTex2D(true);
            }
            // If not using render textures then simply get the images from both cameras
            else
            {
                // store 'black background' image
                texb = GetTex2D(true);

                // store 'white background' image
                texw = GetTex2D(false);
            }

            // If we have both textures then create final output texture
            if (texw && texb)
            {

                int width = Screen.width;
                int height = Screen.height;

                // If we are not using a render texture then the width will only be half the screen
                if (!useRenderTexture)
                {
                    width = width / 2;
                }
                outputtex = new Texture2D(width, height, TextureFormat.ARGB32, false);

                // Create Alpha from the difference between black and white camera renders
                for (int y = 0; y < outputtex.height; ++y)
                { // each row
                    for (int x = 0; x < outputtex.width; ++x)
                    { // each column
                        float alpha;
                        if (useRenderTexture)
                        {
                            alpha = texw.GetPixel(x, y).r - texb.GetPixel(x, y).r;
                        }
                        else
                        {
                            alpha = texb.GetPixel(x + width, y).r - texb.GetPixel(x, y).r;
                        }
                        alpha = 1.0f - alpha;
                        Color color;
                        if (alpha == 0)
                        {
                            color = Color.clear;
                        }
                        else
                        {
                            color = texb.GetPixel(x, y) / alpha;
                        }
                        color.a = alpha;
                        outputtex.SetPixel(x, y, color);
                    }
                }

                // Encode the resulting output texture to a byte array then write to the file
                byte[] pngShot = outputtex.EncodeToPNG();
                File.WriteAllBytes(filename, pngShot);
                print(filename+"  ");
                

                // Reset the time scale, then move on to the next frame.
                Time.timeScale = originaltimescaleTime;
                videoframe++;
            }

            // Debug.Log("Frame " + name + " " + videoframe);
        }
        else
        {
            Debug.Log("Complete! " + videoframe + " videoframes rendered (0 indexed)");
            done = true;
        }
    }

    // Get the texture from the screen, render all or only half of the camera
    private Texture2D GetTex2D(bool renderAll)
    {
        // Create a texture the size of the screen, RGB24 format
        int width = Screen.width;
        int height = Screen.height;
        if (!renderAll)
        {
            width = width / 2;
        }

        Texture2D tex = new Texture2D(width, height, TextureFormat.ARGB32, false);
        // Read screen contents into the texture
        tex.ReadPixels(new Rect(0, 0, width, height), 0, 0);
        tex.Apply();
        return tex;
    }
}本文转自赵青青博客园博客，原文链接：http://www.cnblogs.com/zhaoqingqing/p/3649321.html，如需转载请自行联系原作者