Question I want AR Raycast distance values for every coordinate on the screen

Code (CSharp):

1.             float[,] ray_array = new float[Screen.width + 1, Screen.height + 1];
2.  
3.             for (int y = 0; y <= Screen.height; y++)
4.             {
5.                 for (int x = 0; x <= Screen.width; x++)
6.                 {
7.                     List<ARRaycastHit> hits = new List<ARRaycastHit>();
8.  
9.                     if (ray_manager.Raycast(new Vector2(x, y), hits, TrackableType.Depth))
10.                     {
11.                         ray_array[x, y] = hits[0].distance;
12.                     }
13.                 }
14.             }

I wrote a for loop in this way to get the values of all coordinates, but the for loop is too slow. Is there a way to improve the speed?

 

You would need to read each pixel directly from the depth map.

https://developers.google.com/ar/develop/unity-arf/depth/developer-guide

 

I've already seen that. However, when I tested that, I found that the center of the camera and the depth of the camera are the same even from the distance, so I want to change it to raycast.

 

If it works properly, how should I implement the updaterawimage function in the sample?

 

The page I posted links to a sample here.

I've never played around with the depth image myself and so I can't really help you with the details.

 

I took an XRCPUImage and took a test of the floor. In this case, the depth length of the camera center point should be about 0.36, and the depth length of the otherside should be higher than the center of the camera, but most of the depth is the same at 0.36. I think it comes out well when I debug with raycast, but if raycast is inefficient, is there any other solution?

 

here is my code

Code (CSharp):

1.         public void SaveCpuImageData()
2.         {
3.             if (manager.descriptor.environmentDepthImageSupported == Supported.Supported)
4.             {
5.                 if (manager.TryAcquireEnvironmentDepthCpuImage(out var cpuImage) && cpuImage.valid)
6.                 {
7.                     Assert.IsTrue(cpuImage.planeCount == 1);
8.                     var plane_data = cpuImage.GetPlane(0).data;
9.  
10.                     byte[] byteArray = NativeArrayToByteArray(plane_data);
11.  
12.                     string json = "";
13.  
14.                     switch (cpuImage.format)
15.                     {
16.                         case XRCpuImage.Format.DepthUint16:
17.                             var temp = GetDepthEveryPoint(plane_data, cpuImage.GetPlane(0).pixelStride);
18.                             depthToJson.list = temp;
19.                             json = JsonUtility.ToJson(depthToJson);
20.                             break;
21.                         case XRCpuImage.Format.DepthFloat32:
22.                             var f = BitConverter.ToSingle(byteArray, 0);
23.                             break;
24.  
25.                     }
26.  
27.                     string file_name = "cpuimagedata_" + idx.ToString();
28.  
29.                     if (!System.IO.Directory.Exists(Application.persistentDataPath))
30.                     {                        System.IO.Directory.CreateDirectory(Application.persistentDataPath);
31.                     }
32.  
33.                     string filePath = Application.persistentDataPath + "/" + file_name + ".json";
34.                     System.IO.File.WriteAllText(filePath, json);
35.  
36.                     string imagePath = Application.persistentDataPath + "/" + file_name + ".png";
37.  
38.                     var texture = new Texture2D(cpuImage.width, cpuImage.height, cpuImage.format.AsTextureFormat(), false);
39.  
40.                     var rawTextureData = texture.GetRawTextureData<byte>();
41.                     var conversionParams = new XRCpuImage.ConversionParams(cpuImage, cpuImage.format.AsTextureFormat(), cpuImageSample.m_Transformation);
42.                     cpuImage.Convert(conversionParams, rawTextureData);
43.                     texture.Apply();
44.                    
45.                     System.IO.File.WriteAllBytes(imagePath, texture.EncodeToPNG());
46.  
47.                     string rgbimagePath = Application.persistentDataPath + "/" + file_name + "_rgb.png";
48.                     Texture2D rgbTexture = depthImage.texture as Texture2D;
49.                     System.IO.File.WriteAllBytes(rgbimagePath, rgbTexture.EncodeToPNG());
50.  
51.                     idx++;
52.                 }
53.             }
54.         }
55.  
56.         List<float> GetDepthEveryPoint(NativeArray<byte> nativeArray, int pixelStride)
57.         {
58.             List<float> returnList = new List<float>();
59.  
60.             for (int i = 0; i < nativeArray.Length; i += pixelStride)
61.             {
62.                 var data = nativeArray.GetSubArray(i, pixelStride);
63.                 var d = BitConverter.ToUInt16(data.ToArray(), 0) / 1000f;
64.                 returnList.Add(d);
65.             }
66.  
67.             return returnList;
68.         }

 

You'll need to create a vector3 for each pixel and then use the pixel's vector3 to calculate the magnitude from the screen center's vector3.

 

I'm really sorry, but how should I implement it?

 

I've not tested it but try something like this:

Code (CSharp):

1.         List<float> GetDepthEveryPoint(NativeArray<byte> nativeArray, int pixelStride, int imageWidth,int imageHeight)
2.         {
3.             List<float> returnList = new List<float>();
4.             float distance=0;
5.             int x=0;
6.             int y=0;
7.             float viewScale=0.2f;
8.             for (int i = 0; i < nativeArray.Length; i += pixelStride)
9.             {
10.                 var data = nativeArray.GetSubArray(i, pixelStride);
11.                 var d = BitConverter.ToUInt16(data.ToArray(), 0) / 1000f;
12.                 Vector3 pixelPosition=new Vector3((float)x-(imageWidth/2)*viewScale,(float)y-(imageHeight/2)*viewScale,(float)d);
13.                 distance=Vector3.Magnitude(pixelPosition);
14.                 returnList.Add(distance);
15.                 x++;
16.                 if (x>=imageWidth)
17.                 {
18.                     x=0;
19.                     y+=1;
20.                 }
21.             }
22.             return returnList;
23.         }
24.