Testing strategy

cargo run --example solari --features="bevy_solari https free_camera" to evaluate this without DLSS
cargo run --example solari --features="bevy_solari https free_camera dlss" to evaluate this with DLSS
git checkout main to test on latest main
git checkout 1b0f112d90f1c1031c50aada217423986e674de5 to test main on the PR that broke this
git checkout f1785f65129ec84fbf59afdb3d19eb867a2472f7 to test main just before this broke

My setup

bevy_diagnostic::system_information_diagnostics_plugin::internal: SystemInfo { os: "Windows 11 Home", kernel: "26200", cpu: "Intel(R) Core(TM) Ultra 7 155H", core_count: "16", memory: "15.4 GiB" }
AdapterInfo { name: "NVIDIA GeForce RTX 4060 Laptop GPU", vendor: 4318, device: 10400, device_type: DiscreteGpu, device_pci_bus_id: "0000:01:00.0", driver: "NVIDIA", driver_info: "566.07", backend: Vulkan, subgroup_min_size: 32, subgroup_max_size: 32, transient_saves_memory: false }

Results seen during initial debugging

no flickering on main without DLSS
@JMS55 reports that this only occurs with DLSS enabled (I can reproduce)
@JMS55 reports that this occurs even if the actual DLSS logic is removed, the flickering still occurs
- removing the contents of DlssPlugin disables DLSS (it's all grainy!), but the flickering is gone
- removing the contents of dlss_super_resolution and dlss_ray_reconstruction causes graininess with flickering, reproducing what was reported
on main, I get quite a few Vulkan validation warnings and errors when running without DLSS enabled

Details

2026-03-11T01:50:03.285314Z WARN bevy_pbr::render::mesh_view_bindings: Too many textures in mesh pipeline view layout, this might cause us to hit `wgpu::Limits::max_sampled_textures_per_shader_stage` in some environments. 2026-03-11T01:50:03.340031Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkPresentInfoKHR-pImageIndices-01430 (0x48ad24c6)] vkQueuePresentKHR(): pPresentInfo->pSwapchains[0] images passed to present must be in layout VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR but VkImage 0x2230000000223 is in VK_IMAGE_LAYOUT_UNDEFINED. The Vulkan spec states: Each element of pImageIndices must be the index of a presentable image acquired from the swapchain specified by the corresponding element of the pSwapchains array, and the presented image subresource must be in the VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR layout at the time the operation is executed on a VkDevice (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-VkPresentInfoKHR-pImageIndices-01430) 2026-03-11T01:50:03.340978Z ERROR wgpu_hal::vulkan::instance: objects: (type: IMAGE, hndl: 0x2230000000223, name: ?) 2026-03-11T01:50:06.447982Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkPresentInfoKHR-pImageIndices-01430 (0x48ad24c6)] vkQueuePresentKHR(): pPresentInfo->pSwapchains[0] images passed to present must be in layout VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR but VkImage 0x2230000000223 is in VK_IMAGE_LAYOUT_UNDEFINED. The Vulkan spec states: Each element of pImageIndices must be the index of a presentable image acquired from the swapchain specified by the corresponding element of the pSwapchains array, and the presented image subresource must be in the VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR layout at the time the operation is executed on a VkDevice (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-VkPresentInfoKHR-pImageIndices-01430) ShiftLeft - Fly faster while held 2026-03-11T01:50:03.285314Z WARN bevy_pbr::render::mesh_view_bindings: Too many textures in mesh pipeline view layout, this might cause us to hit `wgpu::Limits::max_sampled_textures_per_shader_stage` in some environments. 2026-03-11T01:50:03.340031Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkPresentInfoKHR-pImageIndices-01430 (0x48ad24c6)] vkQueuePresentKHR(): pPresentInfo->pSwapchains[0] images passed to present must be in layout VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR but VkImage 0x2230000000223 is in VK_IMAGE_LAYOUT_UNDEFINED. The Vulkan spec states: Each element of pImageIndices must be the index of a presentable image acquired from the swapchain specified by the corresponding element of the pSwapchains array, and the presented image subresource must be in the VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR layout at the time the operation is executed on a VkDevice (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-VkPresentInfoKHR-pImageIndices-01430) 2026-03-11T01:50:03.340978Z ERROR wgpu_hal::vulkan::instance: objects: (type: IMAGE, hndl: 0x2230000000223, name: ?) 2026-03-11T01:50:06.447982Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkPresentInfoKHR-pImageIndices-01430 (0x48ad24c6)] vkQueuePresentKHR(): pPresentInfo->pSwapchains[0] images passed to present must be in layout VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR but VkImage 0x2230000000223 is in VK_IMAGE_LAYOUT_UNDEFINED. The Vulkan spec states: Each element of pImageIndices must be the index of a presentable image acquired from the swapchain specified by the corresponding element of the pSwapchains array, and the presented image subresource must be in the VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR layout at the time the operation is executed on a VkDevice (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-VkPresentInfoKHR-pImageIndices-01430) 2026-03-11T01:50:03.340031Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkPresentInfoKHR-pImageIndices-01430 (0x48ad24c6)] vkQueuePresentKHR(): pPresentInfo->pSwapchains[0] images passed to present must be in layout VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR but VkImage 0x2230000000223 is in VK_IMAGE_LAYOUT_UNDEFINED. The Vulkan spec states: Each element of pImageIndices must be the index of a presentable image acquired from the swapchain specified by the corresponding element of the pSwapchains array, and the presented image subresource must be in the VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR layout at the time the operation is executed on a VkDevice (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-VkPresentInfoKHR-pImageIndices-01430) 2026-03-11T01:50:03.340978Z ERROR wgpu_hal::vulkan::instance: objects: (type: IMAGE, hndl: 0x2230000000223, name: ?) 2026-03-11T01:50:06.447982Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkPresentInfoKHR-pImageIndices-01430 (0x48ad24c6)] vkQueuePresentKHR(): pPresentInfo->pSwapchains[0] images passed to present must be in layout VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR but VkImage 0x2230000000223 is in VK_IMAGE_LAYOUT_UNDEFINED. The Vulkan spec states: Each element of pImageIndices must be the index of a presentable image acquired from the swapchain specified by the corresponding element of the pSwapchains array, and the presented image subresource must be in the VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR layout at the time the operation is executed on a VkDevice (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-VkPresentInfoKHR-pImageIndices-01430) SHARED_PRESENT_KHR but VkImage 0x2230000000223 is in VK_IMAGE_LAYOUT_UNDEFINED. The Vulkan spec states: Each element of pImageIndices must be the index of a presentable image acquired from the swapchain specified by the corresponding element of the pSwapchains array, and the presented image subresource must be in the VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR layout at the time the operation is executed on a VkDevice (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-VkPresentInfoKHR-pImageIndices-01430) 2026-03-11T01:50:03.340978Z ERROR wgpu_hal::vulkan::instance: objects: (type: IMAGE, hndl: 0x2230000000223, name: ?) 2026-03-11T01:50:06.447982Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkPresentInfoKHR-pImageIndices-01430 (0x48ad24c6)] vkQueuePresentKHR(): pPresentInfo->pSwapchains[0] images passed to present must be in layout VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR but VkImage 0x2230000000223 is in VK_IMAGE_LAYOUT_UNDEFINED. The Vulkan spec states: Each element of pImageIndices must be the index of a presentable image acquired from the swapchain specified by the corresponding element of the pSwapchains array, and the presented image subresource must be in the VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR layout at the time the operation is executed on a VkDevice (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-VkPresentInfoKHR-pImageIndices-01430) _KHR layout at the time the operation is executed on a VkDevice (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-VkPresentInfoKHR-pImageIndices-01430) 2026-03-11T01:50:03.340978Z ERROR wgpu_hal::vulkan::instance: objects: (type: IMAGE, hndl: 0x2230000000223, name: ?) 2026-03-11T01:50:06.447982Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkPresentInfoKHR-pImageIndices-01430 (0x48ad24c6)] vkQueuePresentKHR(): pPresentInfo->pSwapchains[0] images passed to present must be in layout VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR but VkImage 0x2230000000223 is in VK_IMAGE_LAYOUT_UNDEFINED. The Vulkan spec states: Each element of pImageIndices must be the index of a presentable image acquired from the swapchain specified by the corresponding element of the pSwapchains array, and the presented image subresource must be in the VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR layout at the time the operation is executed on a VkDevice (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-VkPresentInfoKHR-pImageIndices-01430) 2026-03-11T01:50:03.340978Z ERROR wgpu_hal::vulkan::instance: objects: (type: IMAGE, hndl: 0x2230000000223, name: ?) 2026-03-11T01:50:06.447982Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkPresentInfoKHR-pImageIndices-01430 (0x48ad24c6)] vkQueuePresentKHR(): pPresentInfo->pSwapchains[0] images passed to present must be in layout VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR but VkImage 0x2230000000223 is in VK_IMAGE_LAYOUT_UNDEFINED. The Vulkan spec states: Each element of pImageIndices must be the index of a presentable image acquired from the swapchain specified by the corresponding element of the pSwapchains array, and the presented image subresource must be in the VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR layout at the time the operation is executed on a VkDevice (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-VkPresentInfoKHR-pImageIndices-01430) SHARED_PRESENT_KHR but VkImage 0x2230000000223 is in VK_IMAGE_LAYOUT_UNDEFINED. The Vulkan spec states: Each element of pImageIndices must be the index of a presentable image acquired from the swapchain specified by the corresponding element of the pSwapchains array, and the presented image subresource must be in the VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR layout at the time the operation is executed on a VkDevice (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-VkPresentInfoKHR-pImageIndices-01430) 2026-03-11T01:50:06.448479Z ERROR wgpu_hal::vulkan::instance: objects: (type: IMAGE, hndl: 0x2230000000223, name: ?) g element of the pSwapchains array, and the presented image subresource must be in the VK_IMAGE_LAYOUT_PRESENT_SRC_KHR or VK_IMAGE_LAYOUT_SHARED_PRESENT_KHR layout at the time the operation is executed on a VkDevice (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-VkPresentInfoKHR-pImageIndices-01430) 2026-03-11T01:50:06.448479Z ERROR wgpu_hal::vulkan::instance: objects: (type: IMAGE, hndl: 0x2230000000223, name: ?) 2026-03-11T01:50:06.448479Z ERROR wgpu_hal::vulkan::instance: objects: (type: IMAGE, hndl: 0x2230000000223, name: ?) 2026-03-11T01:50:06.603467Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-vkAcquireNextImageKHR-semaphore-01286 (0xe9e4b2a9)] vkAcquireNextImageKHR(): Semaphore must not be currently signaled. The Vulkan spec states: If semaphore is not VK_NULL_HANDLE, it must be unsignaled (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-vkAcquireNextImageKHR-semaphore-01286) vkAcquireNextImageKHR(): Semaphore must not be currently signaled. The Vulkan spec states: If semaphore is not VK_NULL_HANDLE, it must be unsignaled (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-vkAcquireNextImageKHR-semaphore-01286) The Vulkan spec states: If semaphore is not VK_NULL_HANDLE, it must be unsignaled (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-vkAcquireNextImageKHR-semaphore-01286) VUID-vkAcquireNextImageKHR-semaphore-01286) 2026-03-11T01:50:06.603926Z ERROR wgpu_hal::vulkan::instance: objects: (type: SEMAPHORE, hndl: 0x2270000000227, name: SwapchainImageSemaphore: Index 0 acquire) 2026-03-11T01:50:06.636500Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-vkAcquireNextImageKHR-semaphore-01286 (0xe9e4b2a9)] acquire) 2026-03-11T01:50:06.636500Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-vkAcquireNextImageKHR-semaphore-01286 (0xe9e4b2a9)] 2026-03-11T01:50:06.636500Z ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-vkAcquireNextImageKHR-semaphore-01286 (0xe9e4b2a9)] vkAcquireNextImageKHR(): Semaphore must not be currently signaled. The Vulkan spec states: If semaphore is not VK_NULL_HANDLE, it must be unsignaled (https://docs.vulkan.org/spec/latest/chapters/VK_KHR_surface/wsi.html#VUID-vkAcquireNextImageKHR-semaphore-01286) 2026-03-11T01:50:06.636904Z ERROR wgpu_hal::vulkan::instance: objects: (type: SEMAPHORE, hndl: 0x2280000000228, name: SwapchainImageSemaphore: Index 1 acquire)

- more validation errors are present when running with DLSS on

Details

Tracking down what enabling `dlss` does

there are two plugins here: DlssInitPlugin and DlssPlugin
there are three groups of systems added

         .add_systems(
             ExtractSchedule,
             (
                 extract::extract_dlss::<DlssSuperResolutionFeature>,
                 extract::extract_dlss::<DlssRayReconstructionFeature>,
             ),
         )


2. ```rust
            .add_systems(
                Render,
                (
                    prepare::prepare_dlss::<DlssSuperResolutionFeature>,
                    prepare::prepare_dlss::<DlssRayReconstructionFeature>,
                )
                    .in_set(RenderSystems::PrepareViews)
                    .before(prepare_view_targets),
            );

     app.sub_app_mut(RenderApp).add_systems(
         Core3d,
         (node::dlss_super_resolution, node::dlss_ray_reconstruction)
             .chain()
             .before(bloom)
             .in_set(Core3dSystems::PostProcess),
     );


## Hypothesis: system ordering

A system ordering bug is consistent with all of our key observations:

- flickering is the primary problem: an unstable system ordering between frames could result in rendering only working properly some of the time
- this broke after seemingly unrelated code was changed
- removing the actual contents of the DLSS code doesn't fix things

## Preparing a reduction

Deleting:

```rust
        app.sub_app_mut(RenderApp).add_systems(
            Core3d,
            (node::dlss_super_resolution, node::dlss_ray_reconstruction)
                .chain()
                .before(bloom)
                .in_set(Core3dSystems::PostProcess),

fixes the flickering.

Deleting the contents of dlss_super_resolution and dlss_ray_reconstruction does not fix the flickering.

Failing to add the dlss_super_resolution system (and only adding dlss_ray_reconstruction) fixes the flickering.

Leaving the system in place with an empty function signature and body results in flickering, as reported by @JMS55.

I attempted to create a minimal reproduction of the flickering with DLSS disabled using the following code added to AntiAliasPlugin:

        use bevy_core_pipeline::{Core3d, Core3dSystems};
        use bevy_ecs::prelude::*;
        use bevy_post_process::bloom::bloom;
        use bevy_render::RenderApp;

        fn dummy_system() {}

        app.sub_app_mut(RenderApp).add_systems(
            Core3d,
            (dummy_system, dummy_system)
                .chain()
                .before(bloom)
                .in_set(Core3dSystems::PostProcess),
        );

However, no flickering was observed. Something weirder is going on.

Testing strategy

My setup

Results seen during initial debugging

Tracking down what enabling dlss does

Tracking down what enabling `dlss` does

Uh oh!

Uh oh!

Solari with DLSS flickers #23257

Description

Metadata

Metadata

Assignees

Labels

Type

Fields

Projects

Milestone

Relationships

Development

Issue actions