Triangle example hangs on then_signal_fence_and_flush()

[Dromader2137]

• Version of vulkano: 0.34.0
• OS: Linux
• GPU (the selected PhysicalDevice): NVIDIA GeForce RTX 3060 Laptop GPU (NVK GA106)
• GPU Driver: Mesa NVK 24.2.7
• Upload of a reasonably minimal complete main.rs file that demonstrates the issue: Triangle example

Issue

When running the triangle example, the program hangs after exactly 4 frames. Same issue for triangle_v1.3 and teapot. Additionally the window is transparent.

[Dromader2137]

I've done some testing and the same thing happens with ash triangle example and with this C example. However, no such issues are present in more complex Vulkan applications like Factorio or any game running dxvk.

[Dromader2137]

The ash example also spams this validation error

VALIDATION [VUID-vkAcquireNextImageKHR-semaphore-01779 (1461184347)] : Validation Error: [ VUID-vkAcquireNextImageKHR-semaphore-01779 ] Object 0: handle = 0x9fde6b0000000014, type = VK_OBJECT_TYPE_SEMAPHORE; | MessageID = 0x5717e75b | vkAcquireNextImageKHR():  Semaphore must not have any pending operations. The Vulkan spec states: If semaphore is not VK_NULL_HANDLE it must not have any uncompleted signal or wait operations pending (https://www.khronos.org/registry/vulkan/specs/1.3-extensions/html/vkspec.html#VUID-vkAcquireNextImageKHR-semaphore-01779)

This doesn't happen however in vulkano's example modified to use the same validation layers. I only mention it, as vulkano is based on ash and maybe this is an issue on their side and not a problem with vulkano itself.

[Dromader2137]

The code that I used to test this issue:

// Welcome to the triangle example!
//
// This is the only example that is entirely detailed. All the other examples avoid code
// duplication by using helper functions.
//
// This example assumes that you are already more or less familiar with graphics programming and
// that you want to learn Vulkan. This means that for example it won't go into details about what a
// vertex or a shader is.

use std::{error::Error, sync::Arc};
use vulkano::{
    buffer::{Buffer, BufferContents, BufferCreateInfo, BufferUsage, Subbuffer},
    command_buffer::{
        allocator::StandardCommandBufferAllocator, AutoCommandBufferBuilder, CommandBufferUsage,
        RenderPassBeginInfo, SubpassBeginInfo, SubpassContents,
    },
    device::{
        physical::PhysicalDeviceType, Device, DeviceCreateInfo, DeviceExtensions, Queue,
        QueueCreateInfo, QueueFlags,
    },
    image::{view::ImageView, Image, ImageUsage},
    instance::{
        debug::{
            DebugUtilsMessageSeverity, DebugUtilsMessageType, DebugUtilsMessenger,
            DebugUtilsMessengerCallback, DebugUtilsMessengerCreateInfo,
        },
        Instance, InstanceCreateFlags, InstanceCreateInfo,
    },
    memory::allocator::{AllocationCreateInfo, MemoryTypeFilter, StandardMemoryAllocator},
    pipeline::{
        graphics::{
            color_blend::{ColorBlendAttachmentState, ColorBlendState},
            input_assembly::InputAssemblyState,
            multisample::MultisampleState,
            rasterization::RasterizationState,
            vertex_input::{Vertex, VertexDefinition},
            viewport::{Viewport, ViewportState},
            GraphicsPipelineCreateInfo,
        },
        layout::PipelineDescriptorSetLayoutCreateInfo,
        DynamicState, GraphicsPipeline, PipelineLayout, PipelineShaderStageCreateInfo,
    },
    render_pass::{Framebuffer, FramebufferCreateInfo, RenderPass, Subpass},
    swapchain::{
        acquire_next_image, Surface, Swapchain, SwapchainCreateInfo, SwapchainPresentInfo,
    },
    sync::{self, GpuFuture},
    Validated, VulkanError, VulkanLibrary,
};
use winit::{
    application::ApplicationHandler,
    event::WindowEvent,
    event_loop::{ActiveEventLoop, EventLoop},
    window::{Window, WindowId},
};

fn main() -> Result<(), impl Error> {
    let event_loop = EventLoop::new().unwrap();
    let mut app = App::new(&event_loop);

    let _d_callback = unsafe {
        DebugUtilsMessenger::new(
            app.instance.clone(),
            DebugUtilsMessengerCreateInfo {
                message_severity: DebugUtilsMessageSeverity::ERROR
                    | DebugUtilsMessageSeverity::WARNING
                    | DebugUtilsMessageSeverity::INFO
                    | DebugUtilsMessageSeverity::VERBOSE,
                message_type: DebugUtilsMessageType::GENERAL
                    | DebugUtilsMessageType::VALIDATION
                    | DebugUtilsMessageType::PERFORMANCE,
                ..DebugUtilsMessengerCreateInfo::user_callback(DebugUtilsMessengerCallback::new(
                    |message_severity, message_type, callback_data| {
                        let severity = if message_severity
                            .intersects(DebugUtilsMessageSeverity::ERROR)
                        {
                            "error"
                        } else if message_severity.intersects(DebugUtilsMessageSeverity::WARNING) {
                            "warning"
                        } else if message_severity.intersects(DebugUtilsMessageSeverity::INFO) {
                            "information"
                        } else if message_severity.intersects(DebugUtilsMessageSeverity::VERBOSE) {
                            "verbose"
                        } else {
                            panic!("no-impl");
                        };

                        let ty = if message_type.intersects(DebugUtilsMessageType::GENERAL) {
                            "general"
                        } else if message_type.intersects(DebugUtilsMessageType::VALIDATION) {
                            "validation"
                        } else if message_type.intersects(DebugUtilsMessageType::PERFORMANCE) {
                            "performance"
                        } else {
                            panic!("no-impl");
                        };

                        println!(
                            "{} {} {}: {}",
                            callback_data.message_id_name.unwrap_or("unknown"),
                            ty,
                            severity,
                            callback_data.message
                        );
                    },
                ))
            },
        )
    }
    .ok();

    event_loop.run_app(&mut app)
}

struct App {
    instance: Arc<Instance>,
    device: Arc<Device>,
    queue: Arc<Queue>,
    command_buffer_allocator: Arc<StandardCommandBufferAllocator>,
    vertex_buffer: Subbuffer<[MyVertex]>,
    rcx: Option<RenderContext>,
}

struct RenderContext {
    window: Arc<Window>,
    swapchain: Arc<Swapchain>,
    render_pass: Arc<RenderPass>,
    framebuffers: Vec<Arc<Framebuffer>>,
    pipeline: Arc<GraphicsPipeline>,
    viewport: Viewport,
    recreate_swapchain: bool,
    previous_frame_end: Option<Box<dyn GpuFuture>>,
}

impl App {
    fn new(event_loop: &EventLoop<()>) -> Self {
        let library = VulkanLibrary::new().unwrap();

        // The first step of any Vulkan program is to create an instance.
        //
        // When we create an instance, we have to pass a list of extensions that we want to enable.
        //
        // All the window-drawing functionalities are part of non-core extensions that we need to
        // enable manually. To do so, we ask `Surface` for the list of extensions required to draw
        // to a window.
        let required_extensions = Surface::required_extensions(event_loop).unwrap();

        let layers = vec!["VK_LAYER_KHRONOS_validation".to_owned()];

        // Now creating the instance.
        let instance = Instance::new(
            library,
            InstanceCreateInfo {
                // Enable enumerating devices that use non-conformant Vulkan implementations.
                // (e.g. MoltenVK)
                flags: InstanceCreateFlags::ENUMERATE_PORTABILITY,
                enabled_extensions: required_extensions,
                enabled_layers: layers,
                ..Default::default()
            },
        )
        .unwrap();

        // Choose device extensions that we're going to use. In order to present images to a
        // surface, we need a `Swapchain`, which is provided by the `khr_swapchain` extension.
        let device_extensions = DeviceExtensions {
            khr_swapchain: true,
            ..DeviceExtensions::empty()
        };

        // We then choose which physical device to use. First, we enumerate all the available
        // physical devices, then apply filters to narrow them down to those that can support our
        // needs.
        let (physical_device, queue_family_index) = instance
            .enumerate_physical_devices()
            .unwrap()
            .filter(|p| {
                // Some devices may not support the extensions or features that your application,
                // or report properties and limits that are not sufficient for your application.
                // These should be filtered out here.
                p.supported_extensions().contains(&device_extensions)
            })
            .filter_map(|p| {
                // For each physical device, we try to find a suitable queue family that will
                // execute our draw commands.
                //
                // Devices can provide multiple queues to run commands in parallel (for example a
                // draw queue and a compute queue), similar to CPU threads. This is
                // something you have to have to manage manually in Vulkan. Queues
                // of the same type belong to the same queue family.
                //
                // Here, we look for a single queue family that is suitable for our purposes. In a
                // real-world application, you may want to use a separate dedicated transfer queue
                // to handle data transfers in parallel with graphics operations.
                // You may also need a separate queue for compute operations, if
                // your application uses those.
                p.queue_family_properties()
                    .iter()
                    .enumerate()
                    .position(|(i, q)| {
                        // We select a queue family that supports graphics operations. When drawing
                        // to a window surface, as we do in this example, we also need to check
                        // that queues in this queue family are capable of presenting images to the
                        // surface.
                        q.queue_flags.intersects(QueueFlags::GRAPHICS)
                            && p.presentation_support(i as u32, event_loop).unwrap()
                    })
                    // The code here searches for the first queue family that is suitable. If none
                    // is found, `None` is returned to `filter_map`, which
                    // disqualifies this physical device.
                    .map(|i| (p, i as u32))
            })
            // All the physical devices that pass the filters above are suitable for the
            // application. However, not every device is equal, some are preferred over others.
            // Now, we assign each physical device a score, and pick the device with the lowest
            // ("best") score.
            //
            // In this example, we simply select the best-scoring device to use in the application.
            // In a real-world setting, you may want to use the best-scoring device only as a
            // "default" or "recommended" device, and let the user choose the device themself.
            .min_by_key(|(p, _)| {
                // We assign a lower score to device types that are likely to be faster/better.
                match p.properties().device_type {
                    PhysicalDeviceType::DiscreteGpu => 0,
                    PhysicalDeviceType::IntegratedGpu => 1,
                    PhysicalDeviceType::VirtualGpu => 2,
                    PhysicalDeviceType::Cpu => 3,
                    PhysicalDeviceType::Other => 4,
                    _ => 5,
                }
            })
            .expect("no suitable physical device found");

        // Some little debug infos.
        println!(
            "Using device: {} (type: {:?})",
            physical_device.properties().device_name,
            physical_device.properties().device_type,
        );

        // Now initializing the device. This is probably the most important object of Vulkan.
        //
        // An iterator of created queues is returned by the function alongside the device.
        let (device, mut queues) = Device::new(
            // Which physical device to connect to.
            physical_device,
            DeviceCreateInfo {
                // A list of optional features and extensions that our program needs to work
                // correctly. Some parts of the Vulkan specs are optional and must be enabled
                // manually at device creation. In this example the only thing we are going to need
                // is the `khr_swapchain` extension that allows us to draw to a window.
                enabled_extensions: device_extensions,

                // The list of queues that we are going to use. Here we only use one queue, from
                // the previously chosen queue family.
                queue_create_infos: vec![QueueCreateInfo {
                    queue_family_index,
                    ..Default::default()
                }],

                ..Default::default()
            },
        )
        .unwrap();

        // Since we can request multiple queues, the `queues` variable is in fact an iterator. We
        // only use one queue in this example, so we just retrieve the first and only element of
        // the iterator.
        let queue = queues.next().unwrap();

        let memory_allocator = Arc::new(StandardMemoryAllocator::new_default(device.clone()));

        // Before we can start creating and recording command buffers, we need a way of allocating
        // them. Vulkano provides a command buffer allocator, which manages raw Vulkan command
        // pools underneath and provides a safe interface for them.
        let command_buffer_allocator = Arc::new(StandardCommandBufferAllocator::new(
            device.clone(),
            Default::default(),
        ));

        // We now create a buffer that will store the shape of our triangle.
        let vertices = [
            MyVertex {
                position: [-0.5, -0.25],
            },
            MyVertex {
                position: [0.0, 0.5],
            },
            MyVertex {
                position: [0.25, -0.1],
            },
        ];
        let vertex_buffer = Buffer::from_iter(
            memory_allocator,
            BufferCreateInfo {
                usage: BufferUsage::VERTEX_BUFFER,
                ..Default::default()
            },
            AllocationCreateInfo {
                memory_type_filter: MemoryTypeFilter::PREFER_DEVICE
                    | MemoryTypeFilter::HOST_SEQUENTIAL_WRITE,
                ..Default::default()
            },
            vertices,
        )
        .unwrap();

        let rcx = None;

        App {
            instance,
            device,
            queue,
            command_buffer_allocator,
            vertex_buffer,
            rcx,
        }
    }
}

impl ApplicationHandler for App {
    fn resumed(&mut self, event_loop: &ActiveEventLoop) {
        // The objective of this example is to draw a triangle on a window. To do so, we first need
        // to create the window. We use the `WindowBuilder` from the `winit` crate to do that here.
        //
        // Before we can render to a window, we must first create a `vulkano::swapchain::Surface`
        // object from it, which represents the drawable surface of a window. For that we must wrap
        // the `winit::window::Window` in an `Arc`.
        let window = Arc::new(
            event_loop
                .create_window(Window::default_attributes())
                .unwrap(),
        );
        let surface = Surface::from_window(self.instance.clone(), window.clone()).unwrap();
        let window_size = window.inner_size();

        // Before we can draw on the surface, we have to create what is called a swapchain.
        // Creating a swapchain allocates the color buffers that will contain the image that will
        // ultimately be visible on the screen. These images are returned alongside the swapchain.
        let (swapchain, images) = {
            // Querying the capabilities of the surface. When we create the swapchain we can only
            // pass values that are allowed by the capabilities.
            let surface_capabilities = self
                .device
                .physical_device()
                .surface_capabilities(&surface, Default::default())
                .unwrap();

            // Choosing the internal format that the images will have.
            let (image_format, _) = self
                .device
                .physical_device()
                .surface_formats(&surface, Default::default())
                .unwrap()[0];

            // Please take a look at the docs for the meaning of the parameters we didn't mention.
            Swapchain::new(
                self.device.clone(),
                surface,
                SwapchainCreateInfo {
                    // Some drivers report an `min_image_count` of 1, but fullscreen mode requires
                    // at least 2. Therefore we must ensure the count is at least 2, otherwise the
                    // program would crash when entering fullscreen mode on those drivers.
                    min_image_count: surface_capabilities.min_image_count.max(2),

                    image_format,

                    // The size of the window, only used to initially setup the swapchain.
                    //
                    // NOTE:
                    // On some drivers the swapchain extent is specified by
                    // `surface_capabilities.current_extent` and the swapchain size must use this
                    // extent. This extent is always the same as the window size.
                    //
                    // However, other drivers don't specify a value, i.e.
                    // `surface_capabilities.current_extent` is `None`. These drivers will allow
                    // anything, but the only sensible value is the window size.
                    //
                    // Both of these cases need the swapchain to use the window size, so we just
                    // use that.
                    image_extent: window_size.into(),

                    image_usage: ImageUsage::COLOR_ATTACHMENT,

                    // The alpha mode indicates how the alpha value of the final image will behave.
                    // For example, you can choose whether the window will be
                    // opaque or transparent.
                    composite_alpha: surface_capabilities
                        .supported_composite_alpha
                        .into_iter()
                        .next()
                        .unwrap(),

                    ..Default::default()
                },
            )
            .unwrap()
        };

        // The next step is to create the shaders.
        //
        // The raw shader creation API provided by the vulkano library is unsafe for various
        // reasons, so The `shader!` macro provides a way to generate a Rust module from GLSL
        // source - in the example below, the source is provided as a string input directly to the
        // shader, but a path to a source file can be provided as well. Note that the user must
        // specify the type of shader (e.g. "vertex", "fragment", etc.) using the `ty` option of
        // the macro.
        //
        // The items generated by the `shader!` macro include a `load` function which loads the
        // shader using an input logical device. The module also includes type definitions for
        // layout structures defined in the shader source, for example uniforms and push constants.
        //
        // A more detailed overview of what the `shader!` macro generates can be found in the
        // vulkano-shaders crate docs. You can view them at https://docs.rs/vulkano-shaders/
        mod vs {
            vulkano_shaders::shader! {
                ty: "vertex",
                src: r"
                    #version 450

                    layout(location = 0) in vec2 position;

                    void main() {
                        gl_Position = vec4(position, 0.0, 1.0);
                    }
                ",
            }
        }

        mod fs {
            vulkano_shaders::shader! {
                ty: "fragment",
                src: r"
                    #version 450

                    layout(location = 0) out vec4 f_color;

                    void main() {
                        f_color = vec4(1.0, 0.0, 0.0, 1.0);
                    }
                ",
            }
        }

        // The next step is to create a *render pass*, which is an object that describes where the
        // output of the graphics pipeline will go. It describes the layout of the images where the
        // colors, depth and/or stencil information will be written.
        let render_pass = vulkano::single_pass_renderpass!(
            self.device.clone(),
            attachments: {
                // `color` is a custom name we give to the first and only attachment.
                color: {
                    // `format: <ty>` indicates the type of the format of the image. This has to be
                    // one of the types of the `vulkano::format` module (or alternatively one of
                    // your structs that implements the `FormatDesc` trait). Here we use the same
                    // format as the swapchain.
                    format: swapchain.image_format(),
                    // `samples: 1` means that we ask the GPU to use one sample to determine the
                    // value of each pixel in the color attachment. We could use a larger value
                    // (multisampling) for antialiasing. An example of this can be found in
                    // msaa-renderpass.rs.
                    samples: 1,
                    // `load_op: Clear` means that we ask the GPU to clear the content of this
                    // attachment at the start of the drawing.
                    load_op: Clear,
                    // `store_op: Store` means that we ask the GPU to store the output of the draw
                    // in the actual image. We could also ask it to discard the result.
                    store_op: Store,
                },
            },
            pass: {
                // We use the attachment named `color` as the one and only color attachment.
                color: [color],
                // No depth-stencil attachment is indicated with empty brackets.
                depth_stencil: {},
            },
        )
        .unwrap();

        // The render pass we created above only describes the layout of our framebuffers. Before
        // we can draw we also need to create the actual framebuffers.
        //
        // Since we need to draw to multiple images, we are going to create a different framebuffer
        // for each image.
        let framebuffers = window_size_dependent_setup(&images, &render_pass);

        // Before we draw, we have to create what is called a **pipeline**. A pipeline describes
        // how a GPU operation is to be performed. It is similar to an OpenGL program, but it also
        // contains many settings for customization, all baked into a single object. For drawing,
        // we create a **graphics** pipeline, but there are also other types of pipeline.
        let pipeline = {
            // First, we load the shaders that the pipeline will use: the vertex shader and the
            // fragment shader.
            //
            // A Vulkan shader can in theory contain multiple entry points, so we have to specify
            // which one.
            let vs = vs::load(self.device.clone())
                .unwrap()
                .entry_point("main")
                .unwrap();
            let fs = fs::load(self.device.clone())
                .unwrap()
                .entry_point("main")
                .unwrap();

            // Automatically generate a vertex input state from the vertex shader's input
            // interface, that takes a single vertex buffer containing `Vertex` structs.
            let vertex_input_state = MyVertex::per_vertex().definition(&vs).unwrap();

            // Make a list of the shader stages that the pipeline will have.
            let stages = [
                PipelineShaderStageCreateInfo::new(vs),
                PipelineShaderStageCreateInfo::new(fs),
            ];

            // We must now create a **pipeline layout** object, which describes the locations and
            // types of descriptor sets and push constants used by the shaders in the pipeline.
            //
            // Multiple pipelines can share a common layout object, which is more efficient. The
            // shaders in a pipeline must use a subset of the resources described in its pipeline
            // layout, but the pipeline layout is allowed to contain resources that are not present
            // in the shaders; they can be used by shaders in other pipelines that share the same
            // layout. Thus, it is a good idea to design shaders so that many pipelines have common
            // resource locations, which allows them to share pipeline layouts.
            let layout = PipelineLayout::new(
                self.device.clone(),
                // Since we only have one pipeline in this example, and thus one pipeline layout,
                // we automatically generate the creation info for it from the resources used in
                // the shaders. In a real application, you would specify this information manually
                // so that you can re-use one layout in multiple pipelines.
                PipelineDescriptorSetLayoutCreateInfo::from_stages(&stages)
                    .into_pipeline_layout_create_info(self.device.clone())
                    .unwrap(),
            )
            .unwrap();

            // We have to indicate which subpass of which render pass this pipeline is going to be
            // used in. The pipeline will only be usable from this particular subpass.
            let subpass = Subpass::from(render_pass.clone(), 0).unwrap();

            // Finally, create the pipeline.
            GraphicsPipeline::new(
                self.device.clone(),
                None,
                GraphicsPipelineCreateInfo {
                    stages: stages.into_iter().collect(),
                    // How vertex data is read from the vertex buffers into the vertex shader.
                    vertex_input_state: Some(vertex_input_state),
                    // How vertices are arranged into primitive shapes. The default primitive shape
                    // is a triangle.
                    input_assembly_state: Some(InputAssemblyState::default()),
                    // How primitives are transformed and clipped to fit the framebuffer. We use a
                    // resizable viewport, set to draw over the entire window.
                    viewport_state: Some(ViewportState::default()),
                    // How polygons are culled and converted into a raster of pixels. The default
                    // value does not perform any culling.
                    rasterization_state: Some(RasterizationState::default()),
                    // How multiple fragment shader samples are converted to a single pixel value.
                    // The default value does not perform any multisampling.
                    multisample_state: Some(MultisampleState::default()),
                    // How pixel values are combined with the values already present in the
                    // framebuffer. The default value overwrites the old value with the new one,
                    // without any blending.
                    color_blend_state: Some(ColorBlendState::with_attachment_states(
                        subpass.num_color_attachments(),
                        ColorBlendAttachmentState::default(),
                    )),
                    // Dynamic states allows us to specify parts of the pipeline settings when
                    // recording the command buffer, before we perform drawing. Here, we specify
                    // that the viewport should be dynamic.
                    dynamic_state: [DynamicState::Viewport].into_iter().collect(),
                    subpass: Some(subpass.into()),
                    ..GraphicsPipelineCreateInfo::layout(layout)
                },
            )
            .unwrap()
        };

        // Dynamic viewports allow us to recreate just the viewport when the window is resized.
        // Otherwise we would have to recreate the whole pipeline.
        let viewport = Viewport {
            offset: [0.0, 0.0],
            extent: window_size.into(),
            depth_range: 0.0..=1.0,
        };

        // In some situations, the swapchain will become invalid by itself. This includes for
        // example when the window is resized (as the images of the swapchain will no longer match
        // the window's) or, on Android, when the application went to the background and goes back
        // to the foreground.
        //
        // In this situation, acquiring a swapchain image or presenting it will return an error.
        // Rendering to an image of that swapchain will not produce any error, but may or may not
        // work. To continue rendering, we need to recreate the swapchain by creating a new
        // swapchain. Here, we remember that we need to do this for the next loop iteration.
        let recreate_swapchain = false;

        // In the `window_event` handler below we are going to submit commands to the GPU.
        // Submitting a command produces an object that implements the `GpuFuture` trait, which
        // holds the resources for as long as they are in use by the GPU.
        //
        // Destroying the `GpuFuture` blocks until the GPU is finished executing it. In order to
        // avoid that, we store the submission of the previous frame here.
        let previous_frame_end = Some(sync::now(self.device.clone()).boxed());

        self.rcx = Some(RenderContext {
            window,
            swapchain,
            render_pass,
            framebuffers,
            pipeline,
            viewport,
            recreate_swapchain,
            previous_frame_end,
        });
    }

    fn window_event(
        &mut self,
        event_loop: &ActiveEventLoop,
        _window_id: WindowId,
        event: WindowEvent,
    ) {
        let rcx = self.rcx.as_mut().unwrap();

        match event {
            WindowEvent::CloseRequested => {
                event_loop.exit();
            }
            WindowEvent::Resized(_) => {
                rcx.recreate_swapchain = true;
            }
            WindowEvent::RedrawRequested => {
                let window_size = rcx.window.inner_size();

                // Do not draw the frame when the screen size is zero. On Windows, this can occur
                // when minimizing the application.
                if window_size.width == 0 || window_size.height == 0 {
                    return;
                }

                // It is important to call this function from time to time, otherwise resources
                // will keep accumulating and you will eventually reach an out of memory error.
                // Calling this function polls various fences in order to determine what the GPU
                // has already processed, and frees the resources that are no longer needed.
                rcx.previous_frame_end.as_mut().unwrap().cleanup_finished();

                // Whenever the window resizes we need to recreate everything dependent on the
                // window size. In this example that includes the swapchain, the framebuffers and
                // the dynamic state viewport.
                if rcx.recreate_swapchain {
                    // Use the new dimensions of the window.

                    let (new_swapchain, new_images) = rcx
                        .swapchain
                        .recreate(SwapchainCreateInfo {
                            image_extent: window_size.into(),
                            ..rcx.swapchain.create_info()
                        })
                        .expect("failed to recreate swapchain");

                    rcx.swapchain = new_swapchain;

                    // Because framebuffers contains a reference to the old swapchain, we need to
                    // recreate framebuffers as well.
                    rcx.framebuffers = window_size_dependent_setup(&new_images, &rcx.render_pass);

                    rcx.viewport.extent = window_size.into();

                    rcx.recreate_swapchain = false;
                }

                // Before we can draw on the output, we have to *acquire* an image from the
                // swapchain. If no image is available (which happens if you submit draw commands
                // too quickly), then the function will block. This operation returns the index of
                // the image that we are allowed to draw upon.
                //
                // This function can block if no image is available. The parameter is an optional
                // timeout after which the function call will return an error.
                let (image_index, suboptimal, acquire_future) = match acquire_next_image(
                    rcx.swapchain.clone(),
                    None,
                )
                .map_err(Validated::unwrap)
                {
                    Ok(r) => r,
                    Err(VulkanError::OutOfDate) => {
                        rcx.recreate_swapchain = true;
                        return;
                    }
                    Err(e) => panic!("failed to acquire next image: {e}"),
                };

                // `acquire_next_image` can be successful, but suboptimal. This means that the
                // swapchain image will still work, but it may not display correctly. With some
                // drivers this can be when the window resizes, but it may not cause the swapchain
                // to become out of date.
                if suboptimal {
                    rcx.recreate_swapchain = true;
                }

                // In order to draw, we have to record a *command buffer*. The command buffer
                // object holds the list of commands that are going to be executed.
                //
                // Recording a command buffer is an expensive operation (usually a few hundred
                // microseconds), but it is known to be a hot path in the driver and is expected to
                // be optimized.
                //
                // Note that we have to pass a queue family when we create the command buffer. The
                // command buffer will only be executable on that given queue family.
                let mut builder = AutoCommandBufferBuilder::primary(
                    self.command_buffer_allocator.clone(),
                    self.queue.queue_family_index(),
                    CommandBufferUsage::OneTimeSubmit,
                )
                .unwrap();

                builder
                    // Before we can draw, we have to *enter a render pass*.
                    .begin_render_pass(
                        RenderPassBeginInfo {
                            // A list of values to clear the attachments with. This list contains
                            // one item for each attachment in the render pass. In this case, there
                            // is only one attachment, and we clear it with a blue color.
                            //
                            // Only attachments that have `AttachmentLoadOp::Clear` are provided
                            // with clear values, any others should use `None` as the clear value.
                            clear_values: vec![Some([0.0, 0.0, 1.0, 1.0].into())],

                            ..RenderPassBeginInfo::framebuffer(
                                rcx.framebuffers[image_index as usize].clone(),
                            )
                        },
                        SubpassBeginInfo {
                            // The contents of the first (and only) subpass. This can be either
                            // `Inline` or `SecondaryCommandBuffers`. The latter is a bit more
                            // advanced and is not covered here.
                            contents: SubpassContents::Inline,
                            ..Default::default()
                        },
                    )
                    .unwrap()
                    // We are now inside the first subpass of the render pass.
                    //
                    // TODO: Document state setting and how it affects subsequent draw commands.
                    .set_viewport(0, [rcx.viewport.clone()].into_iter().collect())
                    .unwrap()
                    .bind_pipeline_graphics(rcx.pipeline.clone())
                    .unwrap()
                    .bind_vertex_buffers(0, self.vertex_buffer.clone())
                    .unwrap();

                // We add a draw command.
                unsafe { builder.draw(self.vertex_buffer.len() as u32, 1, 0, 0) }.unwrap();

                builder
                    // We leave the render pass. Note that if we had multiple subpasses we could
                    // have called `next_subpass` to jump to the next subpass.
                    .end_render_pass(Default::default())
                    .unwrap();

                // Finish recording the command buffer by calling `end`.
                let command_buffer = builder.build().unwrap();

                println!("1");

                let future = rcx
                    .previous_frame_end
                    .take()
                    .unwrap()
                    .join(acquire_future)
                    .then_execute(self.queue.clone(), command_buffer)
                    .unwrap()
                    // The color output is now expected to contain our triangle. But in order to
                    // show it on the screen, we have to *present* the image by calling
                    // `then_swapchain_present`.
                    //
                    // This function does not actually present the image immediately. Instead it
                    // submits a present command at the end of the queue. This means that it will
                    // only be presented once the GPU has finished executing the command buffer
                    // that draws the triangle.
                    .then_swapchain_present(
                        self.queue.clone(),
                        SwapchainPresentInfo::swapchain_image_index(
                            rcx.swapchain.clone(),
                            image_index,
                        ),
                    );

                println!("2");
                let future = future.then_signal_fence_and_flush();

                println!("3");

                match future.map_err(Validated::unwrap) {
                    Ok(future) => {
                        rcx.previous_frame_end = Some(future.boxed());
                    }
                    Err(VulkanError::OutOfDate) => {
                        rcx.recreate_swapchain = true;
                        rcx.previous_frame_end = Some(sync::now(self.device.clone()).boxed());
                    }
                    Err(e) => {
                        panic!("failed to flush future: {e}");
                        // previous_frame_end = Some(sync::now(device.clone()).boxed());
                    }
                }
            }
            _ => {}
        }
    }

    fn about_to_wait(&mut self, _event_loop: &ActiveEventLoop) {
        let rcx = self.rcx.as_mut().unwrap();
        rcx.window.request_redraw();
    }
}

// We use `#[repr(C)]` here to force rustc to use a defined layout for our data, as the default
// representation has *no guarantees*.
#[derive(BufferContents, Vertex)]
#[repr(C)]
struct MyVertex {
    #[format(R32G32_SFLOAT)]
    position: [f32; 2],
}

/// This function is called once during initialization, then again whenever the window is resized.
fn window_size_dependent_setup(
    images: &[Arc<Image>],
    render_pass: &Arc<RenderPass>,
) -> Vec<Arc<Framebuffer>> {
    images
        .iter()
        .map(|image| {
            let view = ImageView::new_default(image.clone()).unwrap();

            Framebuffer::new(
                render_pass.clone(),
                FramebufferCreateInfo {
                    attachments: vec![view],
                    ..Default::default()
                },
            )
            .unwrap()
        })
        .collect::<Vec<_>>()
}

[marc0246]

Is NVK production-ready? I can't fathom how it could be since it only spawned 2 years ago.

P.S.: There's no need to modify any example; use vkconfig instead. It can inject validation layers into any Vulkan application. It's also not advisable to create the debug messenger that late, as it's not going to be printing anything while initializing the whole app.

[marc0246]

Regarding ash, that's an issue with their example: ash-rs/ash#917. See if ash-rs/ash#941 fixes the validation error. If you get issues with spec-conforming raw Vulkan with something as simple as a triangle, then I'd write this off as a driver bug.

[Dromader2137]

Regarding ash, that's an issue with their example: ash-rs/ash#917. See if ash-rs/ash#941 fixes the validation error. If you get issues with spec-conforming raw Vulkan with something as simple as a triangle, then I'd write this off as a driver bug.

Yeah, the patch fixes validation issues but the window is still transparent. I'll try to check with one more C++ example and if it doesn't work, I'll probably have to attribute this behavior to NVK not being ready even though it is Vulkan 1.3 compliant.

[Dromader2137]

So I have tried the triangle example again, but this time under X11, and it works flawlessly. I'll close this issue as I'm quite sure that the problem lies somewhere in NVK or Hyprland.