Would it make sense to have some kind of "view" or "renderable" handle?

[madsmtm]

I'm only really familiar with macOS and iOS, but on those platforms it would make sense to split the window and the view handles in two.

That way, users could make some sort of interface in the native toolkit, and just provide the NSView handle to wgpu to render into. With the current design, we're assuming that the whole window's content is what should be rendered into.

I think this is roughly how it already works on web, e.g. you can lay out the page in a certain way, and then just create a canvas that you pass on to the renderer to do its thing. (Though arguably winit shouldn't be creating a canvas, perhaps instead it should provide a div that the graphics library itself can insert the canvas into?)

Would this sort of thing work on other platforms?

[MarijnS95]

I think this is roughly how it already works on web

And on android, where NativeWindow is just a silly name for the native wrapper around a Surface and could be any part of the view layout, not necessarily the whole "window surface".

https://github.com/MarijnS95/AndroidNativeSurface

[madsmtm]

Basically, I want better cooperation with the existing layout systems (if they exist).

I'm especially unsure what the best approach is for building a "native" user interface on Linux? GTK? Or would it be best to do it "raw", and provide something like struct XcbViewHandle { visual_id: u32, position: (u32, u32), size: (u32, u32) }?

[kchibisov]

Wayland's wl_surface can be used for anything as well, but that's how the handle is done.

I wonder whether on macOS you don't need to have a reference to a window to perform some requests on it? Also, the user could simply omit the window, fields are not required to be set, so setting just NSView is absolutely fine.

and provide something like struct XcbViewHandle { visual_id: u32, position: (u32, u32), size: (u32, u32) }?

visual has nothing to do with windows on X11, it's a pixel format. Everything is a XID, which is window as it's said in the structs.

[madsmtm]

The window field is entirely redundant on macOS, it can always be gotten from the view.

So maybe it would actually make sense to rename the [Raw]WindowHandle to [Raw]ViewHandle (or similar)?

[MarijnS95]

to [Raw]ViewHandle (or similar)?

The common name for this thing on e.g. Android and in graphics APIs like (E)GL and Vulkan is a "surface", I'd name it that.

OTOH it's not that in Vulkan/GL yet, you still have to create a Surface from a Surface which may sound weird?