如何在 Unity 中创建一个 MutableRuntimeReferenceImageLibrary？

Question

我使用的是 Unity 2021.3.22f1 和 AR Foundation 的 4.2.7 版本。 我已经在我的场景中添加了 AR Session 和 AR Session Origin，以及 AR Tracked Image Manager 作为 AR Session Origin 的一个组件。

我想创建一个 MutableRuntimeReferenceImageLibrary，它在运行时动态添加包含在项目文件夹中的图像。

我写了这段代码：

using System.Collections.Generic;
using UnityEngine;
using UnityEngine.XR.ARFoundation;
using UnityEngine.XR.ARSubsystems;

public class ImageLibraryManager : MonoBehaviour
{
    public ARTrackedImageManager trackedImageManager;
    public string imageFolderPath;

    void Start()
    {
        // Create a list to hold XRReferenceImage objects
        var imageList = new List<XRReferenceImage>();

        // Get the files in the image folder
        var imageFiles = System.IO.Directory.GetFiles(imageFolderPath);

        // Loop through the image files and add them to the list
        foreach (var imageFile in imageFiles)
        {
            // Load the image from the file
            var imageBytes = System.IO.File.ReadAllBytes(imageFile);
            var texture = new Texture2D(2, 2);
            texture.LoadImage(imageBytes);

            var newGuid = System.Guid.NewGuid();
            var guidBytes = newGuid.ToByteArray();
            var image = new XRReferenceImage(
                // Use a new guid for each image
                new SerializableGuid(
                    (ulong)(guidBytes[3] << 24 | guidBytes[2] << 16 | guidBytes[1] << 8 | guidBytes[0]),
                    (ulong)(guidBytes[7] << 24 | guidBytes[6] << 16 | guidBytes[5] << 8 | guidBytes[4])
                ),
                // Use an empty guid for the second parameter
                SerializableGuid.empty,
                // Set the size of the image in meters
                new Vector2(texture.width, texture.height) / 1000f,
                // Set the name of the image
                System.IO.Path.GetFileNameWithoutExtension(imageFile),
                // Set the texture of the image
                texture
            );

            imageList.Add(image);
        }

        // Create a new MutableRuntimeReferenceImageLibrary and assign it to the ARTrackedImageManager
        var imageLibrary = trackedImageManager.CreateRuntimeLibrary() as MutableRuntimeReferenceImageLibrary;
        foreach (var image in imageList)
        {
            // Add each image to the image library
            imageLibrary.AddReferenceImage(image);
        }
        trackedImageManager.referenceLibrary = imageLibrary;
    }
}

但是，这给了我这个错误：

Assets/ImageLibraryManager.cs(53,26): error CS1061: 'MutableRuntimeReferenceImageLibrary' does not contain a definition for 'AddReferenceImage' and no accessible extension method 'AddReferenceImage' accepting a first argument of type 'MutableRuntimeReferenceImageLibrary' could be found (are you missing a using directive or an assembly reference?)

我已经尝试过其他方法，如“Add”或“AddImage”，但它总是给我同样的错误。

你能帮我解决我的问题并创建这种类型的 MutableRuntimeReferenceImageLibrary 吗？

谢谢你

Answer 1

查看评论。我认为您可能需要做的是通过创建自定义类来继承 RuntimeReferenceImageLibrary。然后实例化这个类的一个对象并调用Add方法。这个类并不完美，所以你需要学习如何使用面向对象编程的 C# 创建子类。

https://docs.unity3d.com/Packages/[email protected]/api/UnityEngine.XR.ARSubsystems.RuntimeReferenceImageLibrary.html?q=RuntimeReferenceImageLibrary#methods

public class CustomImageLibrary : RuntimeReferenceImageLibrary
{
    public int count { get; }

    public CustomImageLibrary()
    {
        Console.WriteLine("Constructor.");
    }

    protected XRReferenceImage GetReferenceImageAt(int index)
    {
    }
}

现在实例化名为 imageLibrary 的对象变量。

CustomImageLibrary imageLibrary = new CustomImageLibrary();

现在添加您的图片。