如何从iOS（Objc / Swift）传递结构或类的参数？ （不使用UnitySendMessage）

Question

我试图找到一种将参数从objc / swift中的本机u​​nity插件传递给C＃unity的好方法。

似乎我将需要使用Marshall，但我在任何地方都找不到很好的例子。

我发现的唯一一件事是UnitySendMessage，但是它仅将字符串作为参数传递，甚至那些字符串被限制为1024个字节，这对于对象的JSON表示来说还是不够的，处理多个消息似乎有点过度杀伤力。

这个想法是为了能够从MTLTexture询问插件以进行对象检测，并返回被识别的对象。

代码示例：

SwiftBridge

import Foundation
import UIKit
import Vision

@objc public class SwiftBridge: NSObject {

  var delegate: DelegateCallbackFunction?

  @objc static let shared = SwiftBridge()

  @objc func evaluate(texture: MTLTexture) -> Bool {
    guard let delegate = self.delegate else {
      return false
    }

    let rect = CGRect(x: 1, y: 2, width: 100, height: 200)
    delegate(rect)

    return true
  }

  @objc func setDelegate(callback: @escaping DelegateCallbackFunction) -> Bool {
    self.delegate = callback

    return true
  }
}

团结

using System;
using UnityEngine;
using System.Runtime.InteropServices;
using AOT;

[StructLayout(LayoutKind.Sequential)]
public struct CGPoint {
    public float x;
    public float y;
};

[StructLayout(LayoutKind.Sequential)]
public struct CGSize {
    public float width;
    public float height;
};

[StructLayout(LayoutKind.Sequential)]
public struct CGRect {
    public CGPoint origin;
    public CGSize size;

}


public class UnityBridge : MonoBehaviour {

    #region Declare external C interface    
    // #if UNITY_IOS && !UNITY_EDITOR

    [DllImport("__Internal")]
    private static extern int _vision_detectObjectsIn(IntPtr texture);

    delegate bool ObjectDetectedCallback(ref CGRect rect);
    [DllImport("__Internal")]
    private static extern void _vision_setDelegate(ObjectDetectedCallback callback);

    [MonoPInvokeCallback(typeof(ObjectDetectedCallback))] 
    private static bool delegateMessageReceived(ref CGRect rect) {
        Debug.Log("Message received: " + rect.origin.x);
        return true;
    }
    // #endif
    #endregion

    public void initializeDelegate() {
        if (Application.platform == RuntimePlatform.IPhonePlayer) {
            _vision_setDelegate(delegateMessageReceived);
        }
    }

   #region Wrapped methods and properties
   public void EvaluateTexture(IntPtr texture) {
    initializeDelegate();

    if (texture == IntPtr.Zero) {
      Debug.LogError("[Texture] Pointer to buffer is null.");
      return;
    }

    bool success;

     #if UNITY_IOS && !UNITY_EDITOR
     _vision_detectObjectsIn(texture);
     #endif
   }
   #endregion

   #region Singleton implementation
   private static WeRDetectorUnity _instance;
   public static WeRDetectorUnity Instance {
       get {
           if (_instance == null) {
               var obj = new GameObject("WeRDetectorUnity");
               _instance = obj.AddComponent<WeRDetectorUnity>();
           }
           return _instance;
       }
   }

   void Awake() {
       if (_instance != null) {
           Destroy(gameObject);
           return;
       }

       DontDestroyOnLoad(gameObject);
   }
   #endregion


}

Unity中的消息接收打印不会返回应有的1，而是一个奇怪的指数小数。 有什么想法吗？

Answer 1

您需要为传递参数创建结构，它可以多次使用参数，也可以在主类中访问。

struct Location {
  let latitude:"latitude"
  let longitude: "longitude"
}