Resolved XR SDK Question - Aquired Meshes have no indices on OSX in Unity Editor ? MeshDataAllocator_SetMesh

Hello, I'm currently working on a XR Meshing Plugin for simulating ARMeshManager in the Unity Editor. I got a working version running on windows and marshalling data to my native plugin works as intended.

Now I tried building on OSX, but the Aquired meshes has no index array (thus no triangles).

I tried marshalling the data back to managed land and the data seems to be there and alright.

Here is an example.




The following mesh was aquired and created by ARMeshManager on osx



But the data is fine (this is what I get when I marshal the indices data back to c# and log them)



The same code on windows

 

Here is another screenshot on windows - this is working:




Again: on ios I'm only getting vertices but no indices?
I'm marshalling indices as UInt16[]

 

If you are trying to implement a custom meshing implementation, you need to do so using the XR SDK and build a native plugin. You can get started here: https://create.unity3d.com/vsp-signup-form

 

Hi I have the XR SDK and a native plugin. This is my AquireMesh implementation. "Existing" is the mesh data I set from C#. Works fine on windows, on OSX I only get vertices and no indices in Unity (so meshes without triangles)

 

I just tried again using hardcoded vertices and indices before calling MeshDataAllocator_SetMesh and I get the same result.

 

I just created a simple plugin for osx that reports a hard-coded quad and then prints out the vertex count in C#, and it worked as expected. What are the fields of your

UnityXRMeshDescriptor

? Mine looks like this:

Code (CSharp):

1.     UnityXRMeshDescriptor descriptor = {};
2.     descriptor.positions = s_Positions.data();
3.     descriptor.vertexCount = 4;
4.     descriptor.indices16 = s_Indices.data();
5.     descriptor.indexFormat = kUnityXRIndexFormat16Bit;
6.     descriptor.indexCount = 6;
7.     descriptor.topology = kUnityXRMeshTopologyTriangles;
8.     s_Interface->MeshDataAllocator_SetMesh(allocator, &descriptor);
9.  

Where positions and indices are defined like this:

Code (CSharp):

1. std::vector<UnityXRVector3> s_Positions = {
2.     {-1, -1, 1},
3.     {+1, -1, 1},
4.     {+1, +1, 1},
5.     {-1, +1, 1}
6. };
7.  
8. std::vector<uint16_t> s_Indices = {
9.     0, 3, 1,
10.     3, 2, 1
11. };

 

Thanks for looking into it!

I assume youre also getting the indices/triangles? Vertices did work for me as well.

Ill try your code tomorrow, i didnt hardcode the descriptor completely (just the position and index array so maybe there is actually something missing).

 

Sorry, I meant to say: yes, vertices & indices and they match what I provided from the C++ code. I can also see the mesh in the scene view.

 

Alright your code is working with static vertex and index data. I'll try to figure out when it stops working for me

 

Ok I actually forgot to set the topology and index format when registering my descriptors. Weird that it still worked as expected on windows? But glad it works now on osx too. Thanks again for your help! Greatly appreciated!

 

You need to set those fields, so that is strange that it worked on windows. Maybe Windows has slightly different defaults, or if it was uninitialized memory maybe you "got lucky" with the right value. Glad it works for you now!

 

I guess the defaults just work(?) because I tried the windows plugin on different machines and they all worked.