5

我目前有一款游戏,它可以使用大于 1MB 的大图像作为背景。我确切地知道这个转换应该在什么时候发生,所以我创建了一个加载器类来处理在后台加载这些大图像,但是当我加载图像时,它仍然会冻结发生绘图的主线程。由于这段代码在 360 上运行,我将线程移动到第 4 个硬件线程,但这似乎没有帮助。下面是我正在使用的课程。任何关于为什么我的新内容管理器应该在它自己的线程中中断我的主线程中的绘制的任何想法都将不胜感激。

namespace FileSystem  
{
/// <summary>
/// This is used to reference how many objects reference this texture.
/// Everytime someone references a texture we increase the iNumberOfReferences.
/// When a class calls remove on a specific texture we check to see if anything
/// else is referencing the class, if it is we don't remove it. If there isn't 
/// anything referencing the texture its safe to dispose of.
/// </summary>
class TextureContainer
{
    public uint uiNumberOfReferences = 0;
    public Texture2D texture;
}

/// <summary>
/// This class loads all the files from the Content.
/// </summary>
static class FileManager
{
    static Microsoft.Xna.Framework.Content.ContentManager Content; 
    static EventWaitHandle wh = new AutoResetEvent(false);
    static Dictionary<string, TextureContainer> Texture2DResourceDictionary;
    static List<Texture2D> TexturesToDispose;
    static List<String> TexturesToLoad;
    static int iProcessor = 4;

    private static object threadMutex = new object();
    private static object Texture2DMutex = new object();
    private static object loadingMutex = new object();

    private static bool bLoadingTextures = false;

    /// <summary>
    /// Returns if we are loading textures or not.
    /// </summary>
    public static bool LoadingTexture
    {
        get {
                lock (loadingMutex)
                {
                    return bLoadingTextures;
                }
            }
    }

    /// <summary>
    /// Since this is an static class. This is the constructor for the file loadeder. This is the version
    /// for the Xbox 360.
    /// </summary>
    /// <param name="_Content"></param>
    public static void Initalize(IServiceProvider serviceProvider, string rootDirectory, int _iProcessor )
    {
        Content = new Microsoft.Xna.Framework.Content.ContentManager(serviceProvider, rootDirectory);
        Texture2DResourceDictionary = new Dictionary<string, TextureContainer>();
        TexturesToDispose = new List<Texture2D>();
        iProcessor = _iProcessor;
        CreateThread();
    }

    /// <summary>
    /// Since this is an static class. This is the constructor for the file loadeder.
    /// </summary>
    /// <param name="_Content"></param>
    public static void Initalize(IServiceProvider serviceProvider, string rootDirectory)
    {
        Content = new Microsoft.Xna.Framework.Content.ContentManager(serviceProvider, rootDirectory);
        Texture2DResourceDictionary = new Dictionary<string, TextureContainer>();
        TexturesToDispose = new List<Texture2D>();
        CreateThread();
    }

    /// <summary>
    /// Creates the thread incase we wanted to set up some parameters
    /// Outside of the constructor.
    /// </summary>
    static public void CreateThread()
    {
        Thread t = new Thread(new ThreadStart(StartThread));
        t.Start();

    }

    // This is the function that we thread.
    static public void StartThread()
    {
        //BBSThreadClass BBSTC = (BBSThreadClass)_oData;
        FileManager.Execute();
    }

    /// <summary>
    /// This thread shouldn't be called by the outside world.
    /// It allows the File Manager to loop.
    /// </summary>
    static private void Execute()
    {
        // Make sure our thread is on the correct processor on the XBox 360.
#if WINDOWS 
#else
        Thread.CurrentThread.SetProcessorAffinity(new int[] { iProcessor });
        Thread.CurrentThread.IsBackground = true;
#endif
        // This loop will load textures into ram for us away from the main thread.
        while (true)
        {
            wh.WaitOne();
            // Locking down our data while we process it.
            lock (threadMutex)
            {
                lock (loadingMutex)
                {
                    bLoadingTextures = true;
                }
                bool bContainsKey = false;
                for (int con = 0; con < TexturesToLoad.Count; con++)
                {
                    // If we have already loaded the texture into memory reference
                    // the one in the dictionary.
                    lock (Texture2DMutex)
                    {
                        bContainsKey = Texture2DResourceDictionary.ContainsKey(TexturesToLoad[con]);
                    }

                    if (bContainsKey)
                    {
                        // Do nothing
                    }
                    // Otherwise load it into the dictionary and then reference the
                    // copy in the dictionary
                    else
                    {
                        TextureContainer TC = new TextureContainer();
                        TC.uiNumberOfReferences = 1;    // We start out with 1 referece.
                        // Loading the texture into memory.

                        try
                        {
                            TC.texture = Content.Load<Texture2D>(TexturesToLoad[con]);

                            // This is passed into the dictionary, thus there is only one copy of
                            // the texture in memory.

                            // There is an issue with Sprite Batch and disposing textures.
                            // This will have to wait until its figured out.
                            lock (Texture2DMutex)
                            {
                                bContainsKey = Texture2DResourceDictionary.ContainsKey(TexturesToLoad[con]);
                                Texture2DResourceDictionary.Add(TexturesToLoad[con], TC);
                            }
                            // We don't have the find the reference to the container since we
                            // already have it.
                        }
                        // Occasionally our texture will already by loaded by another thread while 
                        // this thread is operating. This mainly happens on the first level.
                        catch (Exception e)
                        {
                            // If this happens we don't worry about it since this thread only loads
                            // texture data and if its already there we don't need to load it.
                        }
                    }
                    Thread.Sleep(100);
                }
            }
            lock (loadingMutex)
            {
                bLoadingTextures = false;
            }
        }
    }

    static public void LoadTextureList(List<string> _textureList)
    {
        // Ensuring that we can't creating threading problems.
        lock (threadMutex)
        {
            TexturesToLoad = _textureList;
        }
        wh.Set();
    }

    /// <summary>
    /// This loads a 2D texture which represents a 2D grid of Texels.
    /// </summary>
    /// <param name="_textureName">The name of the picture you wish to load.</param>
    /// <returns>Holds the image data.</returns>
    public static Texture2D LoadTexture2D( string _textureName )
    {
        TextureContainer temp;
        lock (Texture2DMutex)
        {
            bool bContainsKey = false;
            // If we have already loaded the texture into memory reference
            // the one in the dictionary.
            lock (Texture2DMutex)
            {
                bContainsKey = Texture2DResourceDictionary.ContainsKey(_textureName);

                if (bContainsKey)
                {
                    temp = Texture2DResourceDictionary[_textureName];
                    temp.uiNumberOfReferences++;    // Incrementing the number of references
                }
                // Otherwise load it into the dictionary and then reference the
                // copy in the dictionary
                else
                {
                    TextureContainer TC = new TextureContainer();
                    TC.uiNumberOfReferences = 1;    // We start out with 1 referece.
                    // Loading the texture into memory.
                    try
                    {
                        TC.texture = Content.Load<Texture2D>(_textureName);

                        // This is passed into the dictionary, thus there is only one copy of
                        // the texture in memory.
                    }
                    // Occasionally our texture will already by loaded by another thread while 
                    // this thread is operating. This mainly happens on the first level.
                    catch(Exception e)
                    {
                        temp = Texture2DResourceDictionary[_textureName];
                        temp.uiNumberOfReferences++;    // Incrementing the number of references
                    }

                    // There is an issue with Sprite Batch and disposing textures.
                    // This will have to wait until its figured out.
                    Texture2DResourceDictionary.Add(_textureName, TC);

                    // We don't have the find the reference to the container since we
                    // already have it.
                    temp = TC;
                }
            }
        }
        // Return a reference to the texture
        return temp.texture;
    }

    /// <summary>
    /// Go through our dictionary and remove any references to the
    /// texture passed in.
    /// </summary>
    /// <param name="texture">Texture to remove from texture dictionary.</param>
    public static void RemoveTexture2D(Texture2D texture)
    {
        foreach (KeyValuePair<string, TextureContainer> pair in Texture2DResourceDictionary)
        {
            // Do our references match?
            if (pair.Value.texture == texture)
            {
                // Only one object or less holds a reference to the 
                // texture. Logically it should be safe to remove.
                if (pair.Value.uiNumberOfReferences <= 1)
                {
                    // Grabing referenc to texture
                    TexturesToDispose.Add(pair.Value.texture);
                    // We are about to release the memory of the texture,
                    // thus we make sure no one else can call this member
                    // in the dictionary.
                    Texture2DResourceDictionary.Remove(pair.Key);
                    // Once we have removed the texture we don't want to create an exception.
                    // So we will stop looking in the list since it has changed.
                    break;
                }
                // More than one Object has a reference to this texture.
                // So we will not be removing it from memory and instead 
                // simply marking down the number of references by 1.
                else
                {
                    pair.Value.uiNumberOfReferences--;
                }
            }
        }
    }

    /*public static void DisposeTextures()
    {
        int Count = TexturesToDispose.Count;
        // If there are any textures to dispose of.
        if (Count > 0)
        {
            for (int con = 0; con < TexturesToDispose.Count; con++)
            {
                // =!THIS REMOVES THE TEXTURE FROM MEMORY!=
                // This is not like a normal dispose. This will actually
                // remove the object from memory. Texture2D is inherited
                // from GraphicsResource which removes it self from 
                // memory on dispose. Very nice for game efficency,
                // but "dangerous" in managed land.
                Texture2D Temp = TexturesToDispose[con];
                Temp.Dispose();
            }
            // Remove textures we've already disposed of.
            TexturesToDispose.Clear();
        }
    }*/

    /// <summary>
    /// This loads a 2D texture which represnets a font.
    /// </summary>
    /// <param name="_textureName">The name of the font you wish to load.</param>
    /// <returns>Holds the font data.</returns>
    public static SpriteFont LoadFont( string _fontName )
    {
        SpriteFont temp = Content.Load<SpriteFont>( _fontName );
        return temp;
    }

    /// <summary>
    /// This loads an XML document.
    /// </summary>
    /// <param name="_textureName">The name of the XML document you wish to load.</param>
    /// <returns>Holds the XML data.</returns>
    public static XmlDocument LoadXML( string _fileName )
    {
        XmlDocument temp = Content.Load<XmlDocument>( _fileName );
        return temp;
    }

    /// <summary>
    /// This loads a sound file.
    /// </summary>
    /// <param name="_fileName"></param>
    /// <returns></returns>
    public static SoundEffect LoadSound( string _fileName )
    {
        SoundEffect temp = Content.Load<SoundEffect>(_fileName);
        return temp;
    }
}
}
4

3 回答 3

2

来自博客文章:Shawn Hargreaves 的Load Screen Animations during Lock Contention

这里是龙!上面的代码可以工作,但可能会使您的加载速度慢数百倍。

原因是每次你从不同的线程触摸图形设备时,框架都会取出一个临界区,以避免出现问题。如果动画不断重绘,动画线程几乎总是拥有这个锁,所以任何时候你的加载函数想要创建一个图形资源,如纹理、顶点缓冲区或着色器,它必须等到动画线程释放它. 如果动画线程只是不断循环在同一段绘制代码上,这可能需要一段时间!

解决方案是通过插入 sleep call 来减慢动画线程的速度,从而阻止它占用图形设备。

但是,在您的情况下,因为您正在加载非常大的连续纹理,您可能只需要重新设计加载功能,以便在用户不需要看到任何动画时发生,因为您会期望有一个锁。

于 2010-04-16T15:14:13.277 回答
1

没有看到其余的代码很难说,但我猜你在某个地方有锁争用。我对加载 10 个大型模型(大约 5 秒的加载时间)进行了快速测试,并且能够在不暂停主线程的情况下将它们加载到单独的线程上。

于 2010-04-30T00:31:17.693 回答
0

问题是我在主线程中加载了大量较小的图形。我将这些添加到列表中以加载到线程中,问题就消失了。

所以你之前的答案是正确的。我只是没有正确使用东西。

于 2010-04-30T15:29:40.917 回答