wgpu_texture example would crash for Nvidia GPU (when manually calling app.window().request_redraw())

[wangxiaochuTHU]

My use case needs to render image frames by wgpu for displaying in slint. The wgpu_texture example is a great basis to understand.

I think I absolutely need a signal to trigger slint to redraw as long as the backend frame gets updated. So I add a slint timer as below to check the image update and then request redrawing.

 let timer = Timer::default();
    timer.start(
        slint::TimerMode::Repeated,
        std::time::Duration::from_millis(30),
        {
            let app_weak = app_weak.clone();
            move || {
                /* send images to the set_rendering_notifier callback*/
                send_updated_image_frame_to_render();
                /* request redraw*/
                if let Some(app) = app_weak.upgrade() {
                    app.window().request_redraw();
                }
            }
        },
    );

The modified app would run well, until the Minimize button was clicked which would cause a crash, reporting that

thread 'main' (54480) panicked at C:\Users...\i-slint-renderer-femtovg-1.14.1\wgpu.rs:60:14:
unable to get next texture from swapchain: Outdated
note: run with RUST_BACKTRACE=1 environment variable to display a backtrace

I found that crash only happens for my discrete GPU. By switching to the core graphics card, the app would run well. I found it may be hard to fix after variants of efforts, even if calling request_redraw in condition as follows.

if app.window().is_visible() && !app.window().is_minimized() {
     app.window().request_redraw();
}

So what is correct way for my use case? Thank you.

[wangxiaochuTHU]

run with RUST_BACKTRACE=1 environment variable

thread 'main' (12520) panicked at C:\Users...\i-slint-renderer-femtovg-1.14.1\wgpu.rs:60:14:
unable to get next texture from swapchain: Outdated
stack backtrace:
0: std::panicking::panic_handler
at /rustc/f37aa9955f03bb1bc6fe08670cb1ecae534b5815/library\std\src\panicking.rs:698
1: core::panicking::panic_fmt
at /rustc/f37aa9955f03bb1bc6fe08670cb1ecae534b5815/library\core\src\panicking.rs:80
2: core::result::unwrap_failed
at /rustc/f37aa9955f03bb1bc6fe08670cb1ecae534b5815/library\core\src\result.rs:1862
3: enum2$<core::result::Resultwgpu::api::surface_texture::SurfaceTexture,wgpu::api::surface_texture::SurfaceError >::expectwgpu::api::surface_texture::SurfaceTexture,wgpu::api::surface_texture::SurfaceError
at C:\Users....rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\core\src\result.rs:1185
4: i_slint_renderer_femtovg::wgpu::impl$1::begin_surface_rendering
at C:\Users...\i-slint-renderer-femtovg-1.14.1\wgpu.rs:60
5: i_slint_renderer_femtovg::FemtoVGRenderer<i_slint_renderer_femtovg::wgpu::WGPUBackend>::internal_render_with_post_callback<i_slint_renderer_femtovg::wgpu::WGPUBackend>
at C:\Users...\i-slint-renderer-femtovg-1.14.1\lib.rs:111
6: i_slint_renderer_femtovg::FemtoVGRenderer<i_slint_renderer_femtovg::wgpu::WGPUBackend>::render<i_slint_renderer_femtovg::wgpu::WGPUBackend>
at C:\Users...\i-slint-renderer-femtovg-1.14.1\lib.rs:96
7: i_slint_backend_winit::renderer::femtovg::impl$3::render
at C:\Users...\i-slint-backend-winit-1.14.1\renderer\femtovg.rs:116
8: i_slint_backend_winit::winitwindowadapter::WinitWindowAdapter::draw
at C:\Users...\i-slint-backend-winit-1.14.1\winitwindowadapter.rs:624
9: i_slint_backend_winit::event_loop::impl$2::window_event
at C:\Users...\i-slint-backend-winit-1.14.1\event_loop.rs:180
10: winit::event_loop::dispatch_event_for_app
at C:\Users...\winit-0.30.12\src\event_loop.rs:642
11: winit::platform::run_on_demand::EventLoopExtRunOnDemand::run_app_on_demand::closure$0<winit::event_loop::EventLoop<i_slint_backend_winit::SlintEvent>,i_slint_backend_winit::event_loop::EventLoopState>
at C:\Users...\winit-0.30.12\src\platform\run_on_demand.rs:76
12: winit::platform_impl::windows::event_loop::impl$3::run_on_demand::closure$0<i_slint_backend_winit::SlintEvent,winit::platform::run_on_demand::EventLoopExtRunOnDemand::run_app_on_demand::closure_env$0<winit::event_loop::EventLoop<i_slint_backend_winit::Slin
at C:\Users...\winit-0.30.12\src\platform_impl\windows\event_loop.rs:264
13: alloc::boxed::impl$30::call_mut<tuple$<enum2$<winit::event::Eventwinit::platform_impl::windows::event_loop::UserEventPlaceholder > >,dyn$<core::ops::function::FnMut<tuple$<enum2$<winit::event::Event<winit::platform_impl::windows::event_loop::UserEventPla
at C:\Users....rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\alloc\src\boxed.rs:2012
14: winit::platform_impl::windows::event_loop::runner::impl$3::call_event_handler::closure$0winit::platform_impl::windows::event_loop::UserEventPlaceholder
at C:\Users...\winit-0.30.12\src\platform_impl\windows\event_loop\runner.rs:236
15: core::panic::unwind_safe::impl$25::call_once<tuple$<>,winit::platform_impl::windows::event_loop::runner::impl$3::call_event_handler::closure_env$0winit::platform_impl::windows::event_loop::UserEventPlaceholder >
at C:\Users....rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\core\src\panic\unwind_safe.rs:274
16: std::panicking::catch_unwind::do_call<core::panic::unwind_safe::AssertUnwindSafe<winit::platform_impl::windows::event_loop::runner::impl$3::call_event_handler::closure_env$0winit::platform_impl::windows::event_loop::UserEventPlaceholder >,tuple$<> >
at C:\Users....rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\panicking.rs:590
17: alloc::collections::vec_deque::impl$1::drop<enum2$<winit::platform_impl::windows::event_loop::runner::BufferedEventwinit::platform_impl::windows::event_loop::UserEventPlaceholder >,alloc::alloc::Global>
18: std::panicking::catch_unwind
at C:\Users....rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\panicking.rs:553
19: std::panic::catch_unwind<core::panic::unwind_safe::AssertUnwindSafe<winit::platform_impl::windows::event_loop::runner::impl$3::call_event_handler::closure_env$0winit::platform_impl::windows::event_loop::UserEventPlaceholder >,tuple$<> >
at C:\Users....rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\panic.rs:359
20: winit::platform_impl::windows::event_loop::runner::EventLoopRunnerwinit::platform_impl::windows::event_loop::UserEventPlaceholder::catch_unwind<winit::platform_impl::windows::event_loop::UserEventPlaceholder,tuple$<>,winit::platform_impl::windows::event_
at C:\Users...\winit-0.30.12\src\platform_impl\windows\event_loop\runner.rs:173
21: winit::platform_impl::windows::event_loop::runner::EventLoopRunnerwinit::platform_impl::windows::event_loop::UserEventPlaceholder::call_event_handlerwinit::platform_impl::windows::event_loop::UserEventPlaceholder
at C:\Users...\winit-0.30.12\src\platform_impl\windows\event_loop\runner.rs:230
22: winit::platform_impl::windows::event_loop::runner::EventLoopRunnerwinit::platform_impl::windows::event_loop::UserEventPlaceholder::send_eventwinit::platform_impl::windows::event_loop::UserEventPlaceholder
at C:\Users...\winit-0.30.12\src\platform_impl\windows\event_loop\runner.rs:210
23: winit::platform_impl::windows::event_loop::WindowData::send_event
at C:\Users...\winit-0.30.12\src\platform_impl\windows\event_loop.rs:129
24: winit::platform_impl::windows::event_loop::public_window_callback_inner::closure$4
at C:\Users...\winit-0.30.12\src\platform_impl\windows\event_loop.rs:1282
25: core::ops::function::FnOnce::call_once<winit::platform_impl::windows::event_loop::public_window_callback_inner::closure_env$4,tuple$<> >
at C:\Users....rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\core\src\ops\function.rs:250
26: core::panic::unwind_safe::impl$25::call_once<tuple$<>,winit::platform_impl::windows::event_loop::public_window_callback_inner::closure_env$4>
at C:\Users....rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\core\src\panic\unwind_safe.rs:274
27: std::panicking::catch_unwind::do_call<core::panic::unwind_safe::AssertUnwindSafewinit::platform_impl::windows::event_loop::public_window_callback_inner::closure_env$4,tuple$<> >
at C:\Users....rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\panicking.rs:590
28: alloc::collections::vec_deque::impl$1::drop<enum2$<winit::platform_impl::windows::event_loop::runner::BufferedEventwinit::platform_impl::windows::event_loop::UserEventPlaceholder >,alloc::alloc::Global>
29: std::panicking::catch_unwind
at C:\Users....rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\panicking.rs:553
30: std::panic::catch_unwind<core::panic::unwind_safe::AssertUnwindSafewinit::platform_impl::windows::event_loop::public_window_callback_inner::closure_env$4,tuple$<> >
at C:\Users....rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\panic.rs:359
31: winit::platform_impl::windows::event_loop::runner::EventLoopRunnerwinit::platform_impl::windows::event_loop::UserEventPlaceholder::catch_unwind<winit::platform_impl::windows::event_loop::UserEventPlaceholder,tuple$<>,winit::platform_impl::windows::event_
at C:\Users...\winit-0.30.12\src\platform_impl\windows\event_loop\runner.rs:173
32: winit::platform_impl::windows::event_loop::public_window_callback_inner
at C:\Users...\winit-0.30.12\src\platform_impl\windows\event_loop.rs:2464
33: winit::platform_impl::windows::event_loop::public_window_callback
at C:\Users...\winit-0.30.12\src\platform_impl\windows\event_loop.rs:1098
34: CallWindowProcW
35: CallWindowProcW
36: windows::Win32::UI::WindowsAndMessaging::CallWindowProcW
at C:\Users...\windows-0.61.3\src\Windows\Win32\UI\WindowsAndMessaging\mod.rs:86
37: accesskit_windows::subclass::wnd_proc
at C:\Users...\accesskit_windows-0.29.2\src\subclass.rs:73
38: CallWindowProcW
39: SendMessageW
40: GetWindowDpiAwarenessContext
41: KiUserCallbackDispatcher
42: NtUserDispatchMessage
43: IsWindowUnicode
44: winit::platform_impl::windows::event_loop::EventLoop<i_slint_backend_winit::SlintEvent>::dispatch_peeked_messages<i_slint_backend_winit::SlintEvent>
at C:\Users...\winit-0.30.12\src\platform_impl\windows\event_loop.rs:419
45: winit::platform_impl::windows::event_loop::EventLoop<i_slint_backend_winit::SlintEvent>::run_on_demand<i_slint_backend_winit::SlintEvent,winit::platform::run_on_demand::EventLoopExtRunOnDemand::run_app_on_demand::closure_env$0<winit::event_loop::EventLoop<
at C:\Users...\winit-0.30.12\src\platform_impl\windows\event_loop.rs:277
46: winit::platform::run_on_demand::impl$0::run_on_demand<i_slint_backend_winit::SlintEvent,winit::platform::run_on_demand::EventLoopExtRunOnDemand::run_app_on_demand::closure_env$0<winit::event_loop::EventLoop<i_slint_backend_winit::SlintEvent>,i_slint_backen
at C:\Users...\winit-0.30.12\src\platform\run_on_demand.rs:89
47: winit::platform::run_on_demand::EventLoopExtRunOnDemand::run_app_on_demand<winit::event_loop::EventLoop<i_slint_backend_winit::SlintEvent>,i_slint_backend_winit::event_loop::EventLoopState>
at C:\Users...\winit-0.30.12\src\platform\run_on_demand.rs:75
48: i_slint_backend_winit::event_loop::EventLoopState::run
at C:\Users...\i-slint-backend-winit-1.14.1\event_loop.rs:564
49: i_slint_backend_winit::impl$3::run_event_loop
at C:\Users...\i-slint-backend-winit-1.14.1\lib.rs:780
50: slint::run_event_loop::closure$0
at C:\Users...\slint-1.14.1\lib.rs:247
51: i_slint_backend_selector::with_platform::closure$0<tuple$<>,slint::run_event_loop::closure_env$0>
at C:\Users...\i-slint-backend-selector-1.14.1\lib.rs:150
52: i_slint_core::context::with_global_context::closure$0<enum2$<core::result::Result<tuple$<>,enum2$<i_slint_core::api::PlatformError> > >,i_slint_backend_selector::with_global_context::closure_env$0<enum2$<core::result::Result<tuple$<>,enum2$<i_slint_core::a
at C:\Users...\i-slint-core-1.14.1\context.rs:117
53: std::thread::local::LocalKey<once_cell::unsync::OnceCell<i_slint_core::context::SlintContext> >::try_with<once_cell::unsync::OnceCell<i_slint_core::context::SlintContext>,i_slint_core::context::with_global_context::closure_env$0<enum2$<core::result::Result
at C:\Users....rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\thread\local.rs:508
54: std::thread::local::LocalKey<once_cell::unsync::OnceCell<i_slint_core::context::SlintContext> >::with<once_cell::unsync::OnceCell<i_slint_core::context::SlintContext>,i_slint_core::context::with_global_context::closure_env$0<enum2$<core::result::Result<tup
at C:\Users....rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\std\src\thread\local.rs:472
55: i_slint_core::context::with_global_context<enum2$<core::result::Result<tuple$<>,enum2$<i_slint_core::api::PlatformError> > >,i_slint_backend_selector::with_global_context::closure_env$0<enum2$<core::result::Result<tuple$<>,enum2$<i_slint_core::api::Platfor
at C:\Users...\i-slint-core-1.14.1\context.rs:116
56: i_slint_backend_selector::with_global_context<enum2$<core::result::Result<tuple$<>,enum2$<i_slint_core::api::PlatformError> > >,i_slint_backend_selector::with_platform::closure_env$0<tuple$<>,slint::run_event_loop::closure_env$0> >
at C:\Users...\i-slint-backend-selector-1.14.1\lib.rs:157
57: i_slint_backend_selector::with_platform<tuple$<>,slint::run_event_loop::closure_env$0>
at C:\Users...\i-slint-backend-selector-1.14.1\lib.rs:150
58: slint::run_event_loop
at C:\Users...\slint-1.14.1\lib.rs:247
59: wgpu_texture::app2::slint_generatedApp::impl$14::run
at .\target\debug\build\wgpu_texture-e45c6b98141c9c9b\out\scene.rs:5443
60: wgpu_texture::app2::main
at .\src\app2.rs:462
61: wgpu_texture::main
at .\src\main.rs:6
62: core::ops::function::FnOnce::call_once<void (*)(),tuple$<> >
at C:\Users....rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\core\src\ops\function.rs:250
63: core::hint::black_box
at C:\Users....rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\src\rust\library\core\src\hint.rs:472
note: Some details are omitted, run with RUST_BACKTRACE=full for a verbose backtrace.
error: process didn't exit successfully: target\debug\wgpu_texture.exe (exit code: 101)

[tronical]

Thanks for reporting this. I think that this is a bug, we should reconfigure the surface and try again, instead of raising a panic. Unfortunately, I don’t have an NVIDIA card or a way to reproduce it.

[wangxiaochuTHU]

Thanks for reporting this. I think that this is a bug, we should reconfigure the surface and try again, instead of raising a panic. Unfortunately, I don’t have an NVIDIA card or a way to reproduce it.

Thanks for your reply and the exact catch of issue, from which I feel strongly that you can fix it without a physical environment.
I will be looking forward to the patch and try it out then.