Hi all, I'm looking to do some C# development with OpenXR and found the Silk.NET library as a conven

Hi all, I'm looking to do some C# development with OpenXR and found the Silk.NET library as a convenient way to get started with this. However, I'm having some trouble finding good documentation for getting started with it. The pages at https://dotnet.github.io/Silk.NET/docs/ are basically just placeholders at this point in time. Can anyone point me in the right direction maybe with some examples as well? My eventual goal is just to use this app to drive various OpenXR haptic devices, so I don't really need a renderer or window

Silk.NET - High-Speed & Advanced .NET Graphics & Compute

Documentation

OOpcode_Hi all, I'm looking to do some C# development with OpenXR and found the Silk.NET...

Lyris the Kitori•5/22/22, 11:52 PM

it should work about the same as using OpenXR in C, so look for C docs

Lyris the Kitori•5/22/22, 11:52 PM

you can get the OpenXR API using XR.GetApiXR.GetApi i believe

Opcode_OP•5/23/22, 12:05 AM

okay, so basically it should be pretty 1 to 1 with the OpenXR api spec, just in C#

Lyris the Kitori•5/23/22, 12:06 AM

mostly yes

Opcode_OP•5/23/22, 12:10 AM

https://github.com/dotnet/Silk.NET/blob/7fba589843e118a388bdd261e1b8221e5a7c76b0/src/OpenXR/Silk.NET.OpenXR/Structs/ActionSetCreateInfo.gen.cs#L55
Any particular reason why these are fixed bytes instead of strings?

GitHub

Silk.NET/ActionSetCreateInfo.gen.cs at 7fba589843e118a388bdd261e1b8...

The high-speed OpenGL, OpenCL, OpenAL, OpenXR, GLFW, SDL, Vulkan, Assimp, and DirectX bindings library your mother warned you about. - Silk.NET/ActionSetCreateInfo.gen.cs at 7fba589843e118a388bdd26...

Lyris the Kitori•5/23/22, 12:13 AM

¯\_(ツ)_/¯

Lyris the Kitori•5/23/22, 12:13 AM

maybe the spec specified it returns an array of max 64 bytes as a string

Lyris the Kitori•5/23/22, 12:13 AM

then the generator ignored the "as a string" part

Opcode_OP•5/23/22, 12:15 AM

Lyris the Kitori•5/23/22, 12:16 AM

ah ye it interpreted a C char* as C# byte array

Lyris the Kitori•5/23/22, 12:16 AM

you can get a string out of it if you get a pointer to the byte array, then use SilkMarshal.PtrToString or smthn

Opcode_OP•5/23/22, 12:17 AM

Well...I need to get a string into it

Lyris the Kitori•5/23/22, 12:17 AM

SilkMarshal.StringToPtr or smthn then

Opcode_OP•5/23/22, 12:18 AM

okay I'll look for that - I really do hate C code with all its char* byte stuff

Lyris the Kitori•5/23/22, 12:18 AM

you can also do Encoding.UTF8.GetBytes(string)Encoding.UTF8.GetBytes(string)

Lyris the Kitori•5/23/22, 12:18 AM

assuming it wants UTF8

Opcode_OP•5/23/22, 12:19 AM

https://www.khronos.org/registry/OpenXR/specs/1.0/html/xrspec.html#string-encoding

Opcode_OP•5/23/22, 12:19 AM

yep - the spec defines UTF-8

Lyris the Kitori•5/23/22, 12:19 AM

yup then you should be able to clear the array to all null bytes, then fill it with the bytes you get from Encoding.UTF8.GetBytesEncoding.UTF8.GetBytes

Opcode_OP•5/23/22, 12:37 AM

Yeah it would be really helpful if this was just a string like it’s supposed to be.

Lyris the Kitori•5/23/22, 12:38 AM

2.x wont have breaking changes
https://github.com/dotnet/Silk.NET/issues/887
so pop a report here and we'll fix it in 3.0

GitHub

Tracking Issue for Bindings Generation & Improvements · Issue #887 ...

TODO We truly invite everyone to send us reports of any place where our bindings are not ideal. This issue will serve as a list of things we should fix in 3.0.

Eagle•5/23/22, 12:53 AM

Not sure if this is fixable by conventional means (if anything). A char pointer in itself can represent many things because it can be combined with an indexer ([<index>][<index>]) or even C strings on top of being a reference to a single 8 bits value (there's no byte type in C). Even an array of char, which narrows it down some, can be used to represent either strings or binary data in C. Semantic intent is probably gonna be difficult to guess from just the type/signature. C strings also don't hold anything special in memory to tell that we're dealing with a string aside from the null-terminating character (\0\0 or 0 as an integer value).

Lyris the Kitori•5/23/22, 12:54 AM

most of our other bindings have extra data we use to determine type but i guess we didnt have that here, so its not really fixable unless we make that data ourself, find some copy of it, or manually fix all the broken parts

Eagle•5/23/22, 12:54 AM

If you assume all of them are strings, it might be weird to see a binding method need a string when a stream of bytes is needed.

Eagle•5/23/22, 12:54 AM

Yeah, it has to be marked manually somehow.

Lyris the Kitori•5/23/22, 12:55 AM

and either way, 2.x isnt getting breaking changes, so it likely wont be fixed in any way till 3.0

Eagle•5/23/22, 12:55 AM

Right. Was just saying in general. I wasn't sure if marking/manual fixes were options for Silk as a whole, and from what I know of C, there's not enough clues to tell what this type of data can hold just from parsing code.

LLyris the Kitori 2.x wont have breaking changes https://github.com/dotnet/Silk.NET/issues/887 so ...

Lyris the Kitori•5/23/22, 12:55 AM

best way to make sure it gets fixed in 3.0 is making a response here

EEagle Not sure if this is fixable by conventional means (if anything). A char pointer ...

Opcode_OP•5/23/22, 2:37 AM

I'm a little surprised at the prevalence of char* or even char[] in any modern code. Since its basically just "a place in memory" it seems inherently unsafe

Lyris the Kitori•5/23/22, 2:37 AM

welcome to C

Lyris the Kitori•5/23/22, 2:37 AM

its the

Lyris the Kitori•5/23/22, 2:37 AM

only

Lyris the Kitori•5/23/22, 2:37 AM

option

Lyris the Kitori•5/23/22, 2:37 AM

that is portable

Opcode_OP•5/23/22, 2:38 AM

must OpenXR be implemented in strictly C? Not C++?

Lyris the Kitori•5/23/22, 2:38 AM

we cant bind to C++

Lyris the Kitori•5/23/22, 2:38 AM

we can only bind to C

Opcode_OP•5/23/22, 2:38 AM

Oh?

Lyris the Kitori•5/23/22, 2:38 AM

we cant call C++ functions from C#

Lyris the Kitori•5/23/22, 2:39 AM

theres no standardized convention for doing so

LLyris the Kitori theres no standardized convention for doing so

Opcode_OP•5/23/22, 2:41 AM

Really? So a .dll written in C++ that you might want to somewhere outside of C++ is just a no-go? It becomes a C library?

Lyris the Kitori•5/23/22, 2:41 AM

you have to bind to it from C, then bind to the C

Lyris the Kitori•5/23/22, 2:42 AM

its how ImGui.NET works at all

Lyris the Kitori•5/23/22, 2:42 AM

given ImGui is C++

Redhacker2•5/23/22, 3:47 AM

Yeah

Redhacker2•5/23/22, 3:47 AM

There is no standard C++ ABI, Each compiler does it differently

Redhacker2•5/23/22, 3:47 AM

C is much easier in that regard

Lyris the Kitori•5/23/22, 3:48 AM

you can pretty much assume a standard ABI with C

Redhacker2•5/23/22, 3:48 AM

Silk.net 3.0 is poised to hopefully change this though

Redhacker2•5/23/22, 3:48 AM

With clangsharp being the basis of silktouch

Hi all, I'm looking to do some C# development with OpenXR and found the Silk.NET library as a conven

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