Is it currently possible to create a (semi-)transparent window on native platforms?

[oliver-moeller]

I am currently working on a fullscreen overlay on Windows.
There are a few things I am still trying to figure out. That includes:

• most importantly: making a window transparent and / or semi-transparent while keeping it's widgets visible (maybe through iced_native or iced_winit?)
• starting a window in fullscreen mode
• getting the window handle (that is specifically the hwnd in Windows)

If anybody could lend a hand, thank you very much!

[hecrj]

making a window transparent and / or semi-transparent while keeping it's widgets visible

This is not possible yet, but I believe it should be a matter of adding a transparent setting to window::Settings (winit supports this) and then clearing the frame with a transparent background color when the option is enabled.

starting a window in fullscreen mode

Returning Mode::Fullscreen in Application::mode should do the trick. However, we need to rethink this design. The mode can currently fall out of sync with the actual window state.

getting the window handle

What would be the use case for this?

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Until these features are implemented, you can achieve all of this by building your event loop on top of winit directly. The integration example showcases how to do this.

[oliver-moeller]

I am unsure whether Linux and Mac would achieve anything by it, but under Windows it would allow access to a lot of features in the winapi, which are not currently implemented in iced (e.g. transparency). My thought was, that exposing the window handle immutably would be easier / faster than implementing everything directly.

However if I can build the loop on winit that covers my use case for the handle, I did not find a way to do that by myself.

Thank you for taking the time!

[valpackett]

Please reopen the issue, this feature is generally useful and is not implemented.

So actually, wgpu doesn't support window transparency yet: gfx-rs/wgpu#687

But I guess that's not an issue with the GL backend.

should be a matter of adding a transparent setting to window::Settings

I'll try implementing that.

[maroider]

The assumption made about with_transparent being unnecessary in 0fdc4e0 does not hold true for me (on Windows 10). Transparency refuses to work for me until I add .with_transparent(true) here.

[atsuzaki]

The assumption made about with_transparent being unnecessary in 0fdc4e0 does not hold true for me (on Windows 10). Transparency refuses to work for me until I add .with_transparent(true) here.

It seems to not work on MacOS without .with_transparent(true) as well.

should be a matter of adding a transparent setting to window::Settings

I can open a PR to add this, but I'm not too sure since wgpu still doesn't support it. Maybe I could just add a note for people to switch to GL if they need transparency? cc: @hecrj

[hecrj]

@atsuzaki Sounds good. No need to worry about wgpu for now. Once it's supported, it shouldn't affect the public API.