maybe got xr working?

Cargo.toml

@@ -7,6 +7,7 @@ edition = "2021"
 
 [dependencies]
 anyhow = "1.0.75"
+ash = "0.37.3"
 bevy = { git = "https://github.com/awtterpip/bevy", default-features = false, features = ["bevy_render"] }
 openxr = "0.17.1"
 wgpu = "0.16.0"

examples/xr.rs

@@ -1,6 +1,6 @@
 //! A simple 3D scene with light shining over a cube sitting on a plane.
-use bevy_openxr::DefaultXrPlugins;
+use bevy_openxr::{DefaultXrPlugins, LEFT_XR_TEXTURE_HANDLE, RIGHT_XR_TEXTURE_HANDLE};
-use bevy::prelude::*;
+use bevy::{prelude::*, render::camera::RenderTarget};
 
 fn main() {
     App::new()
@@ -43,4 +43,23 @@ fn setup(
         transform: Transform::from_xyz(-2.0, 2.5, 5.0).looking_at(Vec3::ZERO, Vec3::Y),
         ..default()
     });
+
+    commands.spawn(Camera3dBundle {
+        transform: Transform::from_xyz(-2.0, 2.5, 5.0).looking_at(Vec3::ZERO, Vec3::Y),
+        camera: Camera {
+            order: -1,
+            target: RenderTarget::TextureView(LEFT_XR_TEXTURE_HANDLE),
+            ..default()
+        },
+        ..default()
+    });
+    commands.spawn(Camera3dBundle {
+        transform: Transform::from_xyz(-2.0, 2.5, 5.0).looking_at(Vec3::ZERO, Vec3::Y),
+        camera: Camera {
+            order: -1,
+            target: RenderTarget::TextureView(RIGHT_XR_TEXTURE_HANDLE),
+            ..default()
+        },
+        ..default()
+    });
 }

src/graphics/mod.rs

@@ -0,0 +1,12 @@
+mod vulkan;
+
+use bevy::render::renderer::{RenderDevice, RenderQueue, RenderAdapterInfo, RenderAdapter};
+use bevy::window::RawHandleWrapper;
+use wgpu::Instance;
+
+use crate::input::XrInput;
+use crate::resources::{XrInstance, XrSession, XrEnvironmentBlendMode, XrSessionRunning, XrFrameWaiter, XrSwapchain, XrViews};
+
+pub fn initialize_xr_graphics(window: Option<RawHandleWrapper>) -> anyhow::Result<(RenderDevice, RenderQueue, RenderAdapterInfo, RenderAdapter, Instance, XrInstance, XrSession, XrEnvironmentBlendMode, XrSessionRunning, XrFrameWaiter, XrSwapchain, XrInput, XrViews)>{
+    vulkan::initialize_xr_graphics(window)
+}

src/graphics/vulkan.rs

@@ -0,0 +1,441 @@
+use std::ffi::{c_void, CString};
+use std::sync::{Arc, Mutex};
+use std::sync::atomic::AtomicBool;
+
+use anyhow::Context;
+use ash::vk::{self, Handle};
+use bevy::math::uvec2;
+use bevy::prelude::*;
+use bevy::render::renderer::{RenderAdapter, RenderAdapterInfo, RenderDevice, RenderQueue};
+use bevy::window::RawHandleWrapper;
+use openxr as xr;
+use wgpu::Instance;
+
+use crate::input::XrInput;
+use crate::resources::{
+    XrEnvironmentBlendMode, XrFrameWaiter, XrInstance, XrSession, XrSessionRunning, XrSwapchain, Swapchain, SwapchainInner, XrViews,
+};
+use crate::VIEW_TYPE;
+
+pub fn initialize_xr_graphics(window: Option<RawHandleWrapper>) -> anyhow::Result<(
+    RenderDevice,
+    RenderQueue,
+    RenderAdapterInfo,
+    RenderAdapter,
+    Instance,
+    XrInstance,
+    XrSession,
+    XrEnvironmentBlendMode,
+    XrSessionRunning,
+    XrFrameWaiter,
+    XrSwapchain,
+    XrInput,
+    XrViews,
+)> {
+    use wgpu_hal::{api::Vulkan as V, Api};
+
+    let xr_entry = unsafe { xr::Entry::load() }?;
+
+    let available_extensions = xr_entry.enumerate_extensions()?;
+    assert!(available_extensions.khr_vulkan_enable2);
+    info!("available xr exts: {:#?}", available_extensions);
+
+    let mut enabled_extensions = xr::ExtensionSet::default();
+    enabled_extensions.khr_vulkan_enable2 = true;
+    #[cfg(target_os = "android")]
+    {
+        enabled_extensions.khr_android_create_instance = true;
+    }
+
+    let available_layers = xr_entry.enumerate_layers()?;
+    info!("available xr layers: {:#?}", available_layers);
+
+    let xr_instance = xr_entry.create_instance(
+        &xr::ApplicationInfo {
+            application_name: "Ambient",
+            ..Default::default()
+        },
+        &enabled_extensions,
+        &[],
+    )?;
+    info!("created instance");
+    let instance_props = xr_instance.properties()?;
+    let xr_system_id = xr_instance.system(xr::FormFactor::HEAD_MOUNTED_DISPLAY)?;
+    info!("created system");
+    let system_props = xr_instance.system_properties(xr_system_id).unwrap();
+    info!(
+        "loaded OpenXR runtime: {} {} {}",
+        instance_props.runtime_name,
+        instance_props.runtime_version,
+        if system_props.system_name.is_empty() {
+            "<unnamed>"
+        } else {
+            &system_props.system_name
+        }
+    );
+
+    let blend_mode = xr_instance.enumerate_environment_blend_modes(xr_system_id, VIEW_TYPE)?[0];
+
+    let vk_target_version = vk::make_api_version(0, 1, 1, 0);
+    let vk_target_version_xr = xr::Version::new(1, 1, 0);
+    let reqs = xr_instance.graphics_requirements::<xr::Vulkan>(xr_system_id)?;
+    if vk_target_version_xr < reqs.min_api_version_supported
+        || vk_target_version_xr.major() > reqs.max_api_version_supported.major()
+    {
+        panic!(
+            "OpenXR runtime requires Vulkan version > {}, < {}.0.0",
+            reqs.min_api_version_supported,
+            reqs.max_api_version_supported.major() + 1
+        );
+    }
+
+    let vk_entry = unsafe { ash::Entry::load() }?;
+    let flags = wgpu_hal::InstanceFlags::empty();
+    let extensions =
+        <V as Api>::Instance::required_extensions(&vk_entry, vk_target_version, flags)?;
+    let device_extensions = vec![
+        ash::extensions::khr::Swapchain::name(),
+        ash::extensions::khr::DrawIndirectCount::name(),
+    ];
+    info!(
+        "creating vulkan instance with these extensions: {:#?}",
+        extensions
+    );
+
+    let vk_instance = unsafe {
+        let extensions_cchar: Vec<_> = extensions.iter().map(|s| s.as_ptr()).collect();
+
+        let app_name = CString::new("Ambient")?;
+        let vk_app_info = vk::ApplicationInfo::builder()
+            .application_name(&app_name)
+            .application_version(1)
+            .engine_name(&app_name)
+            .engine_version(1)
+            .api_version(vk_target_version);
+
+        let vk_instance = xr_instance
+            .create_vulkan_instance(
+                xr_system_id,
+                std::mem::transmute(vk_entry.static_fn().get_instance_proc_addr),
+                &vk::InstanceCreateInfo::builder()
+                    .application_info(&vk_app_info)
+                    .enabled_extension_names(&extensions_cchar) as *const _
+                    as *const _,
+            )
+            .context("XR error creating Vulkan instance")
+            .unwrap()
+            .map_err(vk::Result::from_raw)
+            .context("Vulkan error creating Vulkan instance")
+            .unwrap();
+
+        ash::Instance::load(
+            vk_entry.static_fn(),
+            vk::Instance::from_raw(vk_instance as _),
+        )
+    };
+    info!("created vulkan instance");
+
+    let vk_instance_ptr = vk_instance.handle().as_raw() as *const c_void;
+
+    let vk_physical_device = vk::PhysicalDevice::from_raw(unsafe {
+        xr_instance.vulkan_graphics_device(xr_system_id, vk_instance.handle().as_raw() as _)? as _
+    });
+    let vk_physical_device_ptr = vk_physical_device.as_raw() as *const c_void;
+
+    let vk_device_properties =
+        unsafe { vk_instance.get_physical_device_properties(vk_physical_device) };
+    if vk_device_properties.api_version < vk_target_version {
+        unsafe { vk_instance.destroy_instance(None) }
+        panic!("Vulkan physical device doesn't support version 1.1");
+    }
+
+    let wgpu_vk_instance = unsafe {
+        <V as Api>::Instance::from_raw(
+            vk_entry.clone(),
+            vk_instance.clone(),
+            vk_target_version,
+            0,
+            extensions,
+            flags,
+            false,
+            Some(Box::new(())),
+        )?
+    };
+
+    let wgpu_features = wgpu::Features::TEXTURE_ADAPTER_SPECIFIC_FORMAT_FEATURES
+        | wgpu::Features::MULTIVIEW
+        | wgpu::Features::MULTI_DRAW_INDIRECT_COUNT
+        | wgpu::Features::MULTI_DRAW_INDIRECT;
+
+    let wgpu_exposed_adapter = wgpu_vk_instance
+        .expose_adapter(vk_physical_device)
+        .context("failed to expose adapter")?;
+
+    let enabled_extensions = wgpu_exposed_adapter
+        .adapter
+        .required_device_extensions(wgpu_features);
+
+    let (wgpu_open_device, vk_device_ptr, queue_family_index) = {
+        let extensions_cchar: Vec<_> = device_extensions.iter().map(|s| s.as_ptr()).collect();
+        let mut enabled_phd_features = wgpu_exposed_adapter
+            .adapter
+            .physical_device_features(&enabled_extensions, wgpu_features);
+        let family_index = 0;
+        let family_info = vk::DeviceQueueCreateInfo::builder()
+            .queue_family_index(family_index)
+            .queue_priorities(&[1.0])
+            .build();
+        let family_infos = [family_info];
+        let info = enabled_phd_features
+            .add_to_device_create_builder(
+                vk::DeviceCreateInfo::builder()
+                    .queue_create_infos(&family_infos)
+                    .push_next(&mut vk::PhysicalDeviceMultiviewFeatures {
+                        multiview: vk::TRUE,
+                        ..Default::default()
+                    }),
+            )
+            .enabled_extension_names(&extensions_cchar)
+            .build();
+        let vk_device = unsafe {
+            let vk_device = xr_instance
+                .create_vulkan_device(
+                    xr_system_id,
+                    std::mem::transmute(vk_entry.static_fn().get_instance_proc_addr),
+                    vk_physical_device.as_raw() as _,
+                    &info as *const _ as *const _,
+                )
+                .context("XR error creating Vulkan device")?
+                .map_err(vk::Result::from_raw)
+                .context("Vulkan error creating Vulkan device")?;
+
+            ash::Device::load(vk_instance.fp_v1_0(), vk::Device::from_raw(vk_device as _))
+        };
+        let vk_device_ptr = vk_device.handle().as_raw() as *const c_void;
+
+        let wgpu_open_device = unsafe {
+            wgpu_exposed_adapter.adapter.device_from_raw(
+                vk_device,
+                true,
+                &enabled_extensions,
+                wgpu_features,
+                family_info.queue_family_index,
+                0,
+            )
+        }?;
+
+        (
+            wgpu_open_device,
+            vk_device_ptr,
+            family_info.queue_family_index,
+        )
+    };
+
+    let wgpu_instance =
+        unsafe { wgpu::Instance::from_hal::<wgpu_hal::api::Vulkan>(wgpu_vk_instance) };
+    let wgpu_adapter = unsafe { wgpu_instance.create_adapter_from_hal(wgpu_exposed_adapter) };
+    let (wgpu_device, wgpu_queue) = unsafe {
+        wgpu_adapter.create_device_from_hal(
+            wgpu_open_device,
+            &wgpu::DeviceDescriptor {
+                label: None,
+                features: wgpu_features,
+                limits: wgpu::Limits {
+                    max_bind_groups: 8,
+                    max_storage_buffer_binding_size: wgpu_adapter
+                        .limits()
+                        .max_storage_buffer_binding_size,
+                    max_push_constant_size: 4,
+                    ..Default::default()
+                },
+            },
+            None,
+        )
+    }?;
+
+    let (session, frame_wait, frame_stream) = unsafe {
+        xr_instance.create_session::<xr::Vulkan>(
+            xr_system_id,
+            &xr::vulkan::SessionCreateInfo {
+                instance: vk_instance_ptr,
+                physical_device: vk_physical_device_ptr,
+                device: vk_device_ptr,
+                queue_family_index,
+                queue_index: 0,
+            },
+        )
+    }?;
+
+    let views = xr_instance.enumerate_view_configuration_views(xr_system_id, VIEW_TYPE)?;
+
+    let surface = window.map(|wrapper| unsafe {
+        // SAFETY: Plugins should be set up on the main thread.
+        let handle = wrapper.get_handle();
+        wgpu_instance
+            .create_surface(&handle)
+            .expect("Failed to create wgpu surface")
+    });
+    let swapchain_format = surface
+            .as_ref()
+            .map(|surface| surface.get_capabilities(&wgpu_adapter).formats[0])
+            .unwrap_or(wgpu::TextureFormat::Rgba8UnormSrgb);
+
+    let resolution = uvec2(views[0].recommended_image_rect_width, views[0].recommended_image_rect_height);
+
+    let handle = session
+        .create_swapchain(&xr::SwapchainCreateInfo {
+            create_flags: xr::SwapchainCreateFlags::EMPTY,
+            usage_flags: xr::SwapchainUsageFlags::COLOR_ATTACHMENT
+                | xr::SwapchainUsageFlags::SAMPLED,
+            format: wgpu_to_vulkan(swapchain_format).as_raw() as _,
+            // The Vulkan graphics pipeline we create is not set up for multisampling,
+            // so we hardcode this to 1. If we used a proper multisampling setup, we
+            // could set this to `views[0].recommended_swapchain_sample_count`.
+            sample_count: 1,
+            width: resolution.x,
+            height: resolution.y,
+            face_count: 1,
+            array_size: 2,
+            mip_count: 1,
+        })
+        .unwrap();
+    let images = handle.enumerate_images().unwrap();
+
+    let buffers = images
+            .into_iter()
+            .map(|color_image| {
+                let color_image = vk::Image::from_raw(color_image);
+                let wgpu_hal_texture = unsafe {
+                    <V as Api>::Device::texture_from_raw(
+                        color_image,
+                        &wgpu_hal::TextureDescriptor {
+                            label: Some("VR Swapchain"),
+                            size: wgpu::Extent3d {
+                                width: resolution.x,
+                                height: resolution.y,
+                                depth_or_array_layers: 2,
+                            },
+                            mip_level_count: 1,
+                            sample_count: 1,
+                            dimension: wgpu::TextureDimension::D2,
+                            format: swapchain_format,
+                            usage: wgpu_hal::TextureUses::COLOR_TARGET
+                                | wgpu_hal::TextureUses::COPY_DST,
+                            memory_flags: wgpu_hal::MemoryFlags::empty(),
+                            view_formats: vec![],
+                        },
+                        None,
+                    )
+                };
+                let texture = unsafe {
+                    wgpu_device.create_texture_from_hal::<V>(
+                        wgpu_hal_texture,
+                        &wgpu::TextureDescriptor {
+                            label: Some("VR Swapchain"),
+                            size: wgpu::Extent3d {
+                                width: resolution.x,
+                                height: resolution.y,
+                                depth_or_array_layers: 2,
+                            },
+                            mip_level_count: 1,
+                            sample_count: 1,
+                            dimension: wgpu::TextureDimension::D2,
+                            format: swapchain_format,
+                            usage: wgpu::TextureUsages::RENDER_ATTACHMENT
+                                | wgpu::TextureUsages::COPY_DST,
+                            view_formats: &[],
+                        },
+                    )
+                };
+                texture
+            })
+            .collect();
+    
+
+    Ok((
+        wgpu_device.into(),
+        RenderQueue(Arc::new(wgpu_queue)),
+        RenderAdapterInfo(wgpu_adapter.get_info()),
+        RenderAdapter(Arc::new(wgpu_adapter)),
+        wgpu_instance,
+        xr_instance.clone().into(),
+        session.clone().into_any_graphics().into(),
+        blend_mode.into(),
+        AtomicBool::new(false).into(),
+        Mutex::new(frame_wait).into(),
+        Mutex::new(Swapchain::Vulkan(SwapchainInner {
+            stream: frame_stream,
+            handle,
+            resolution,
+            buffers,
+        })).into(),
+        XrInput::new(xr_instance, session.into_any_graphics())?,
+        Mutex::default().into(),
+    ))
+}
+
+fn wgpu_to_vulkan(format: wgpu::TextureFormat) -> vk::Format {
+    use vk::Format;
+    match format {
+        wgpu::TextureFormat::R8Unorm => Format::R8_UNORM,
+        wgpu::TextureFormat::R8Snorm => Format::R8_SNORM,
+        wgpu::TextureFormat::R8Uint => Format::R8_UINT,
+        wgpu::TextureFormat::R8Sint => Format::R8_SINT,
+        wgpu::TextureFormat::R16Uint => Format::R16_UINT,
+        wgpu::TextureFormat::R16Sint => Format::R16_SINT,
+        wgpu::TextureFormat::R16Unorm => Format::R16_UNORM,
+        wgpu::TextureFormat::R16Snorm => Format::R16_SNORM,
+        wgpu::TextureFormat::R16Float => Format::R16_SFLOAT,
+        wgpu::TextureFormat::Rg8Unorm => Format::R8G8_UNORM,
+        wgpu::TextureFormat::Rg8Snorm => Format::R8G8_SNORM,
+        wgpu::TextureFormat::Rg8Uint => Format::R8G8_UINT,
+        wgpu::TextureFormat::Rg8Sint => Format::R8G8_SINT,
+        wgpu::TextureFormat::R32Uint => Format::R32_UINT,
+        wgpu::TextureFormat::R32Sint => Format::R32_SINT,
+        wgpu::TextureFormat::R32Float => Format::R32_SFLOAT,
+        wgpu::TextureFormat::Rg16Uint => Format::R16G16_UINT,
+        wgpu::TextureFormat::Rg16Sint => Format::R16G16_SINT,
+        wgpu::TextureFormat::Rg16Unorm => Format::R16G16_UNORM,
+        wgpu::TextureFormat::Rg16Snorm => Format::R16G16_SNORM,
+        wgpu::TextureFormat::Rg16Float => Format::R16G16_SFLOAT,
+        wgpu::TextureFormat::Rgba8Unorm => Format::R8G8B8A8_UNORM,
+        wgpu::TextureFormat::Rgba8UnormSrgb => Format::R8G8B8A8_SRGB,
+        wgpu::TextureFormat::Rgba8Snorm => Format::R8G8B8A8_SNORM,
+        wgpu::TextureFormat::Rgba8Uint => Format::R8G8B8A8_UINT,
+        wgpu::TextureFormat::Rgba8Sint => Format::R8G8B8A8_SINT,
+        wgpu::TextureFormat::Bgra8Unorm => Format::B8G8R8A8_UNORM,
+        wgpu::TextureFormat::Bgra8UnormSrgb => Format::B8G8R8A8_SRGB,
+        wgpu::TextureFormat::Rgb9e5Ufloat => Format::E5B9G9R9_UFLOAT_PACK32, // this might be the wrong type??? i can't tell
+        wgpu::TextureFormat::Rgb10a2Unorm => Format::A2R10G10B10_UNORM_PACK32,
+        wgpu::TextureFormat::Rg11b10Float => panic!("this texture type invokes nothing but fear within my soul and i don't think vulkan has a proper type for this"),
+        wgpu::TextureFormat::Rg32Uint => Format::R32G32_UINT,
+        wgpu::TextureFormat::Rg32Sint => Format::R32G32_SINT,
+        wgpu::TextureFormat::Rg32Float => Format::R32G32_SFLOAT,
+        wgpu::TextureFormat::Rgba16Uint => Format::R16G16B16A16_UINT,
+        wgpu::TextureFormat::Rgba16Sint => Format::R16G16B16A16_SINT,
+        wgpu::TextureFormat::Rgba16Unorm => Format::R16G16B16A16_UNORM,
+        wgpu::TextureFormat::Rgba16Snorm => Format::R16G16B16A16_SNORM,
+        wgpu::TextureFormat::Rgba16Float => Format::R16G16B16A16_SFLOAT,
+        wgpu::TextureFormat::Rgba32Uint => Format::R32G32B32A32_UINT,
+        wgpu::TextureFormat::Rgba32Sint => Format::R32G32B32A32_SINT,
+        wgpu::TextureFormat::Rgba32Float => Format::R32G32B32A32_SFLOAT,
+        wgpu::TextureFormat::Stencil8 => Format::S8_UINT,
+        wgpu::TextureFormat::Depth16Unorm => Format::D16_UNORM,
+        wgpu::TextureFormat::Depth24Plus => Format::X8_D24_UNORM_PACK32,
+        wgpu::TextureFormat::Depth24PlusStencil8 => Format::D24_UNORM_S8_UINT,
+        wgpu::TextureFormat::Depth32Float => Format::D32_SFLOAT,
+        wgpu::TextureFormat::Depth32FloatStencil8 => Format::D32_SFLOAT_S8_UINT,
+        wgpu::TextureFormat::Etc2Rgb8Unorm => Format::ETC2_R8G8B8_UNORM_BLOCK,
+        wgpu::TextureFormat::Etc2Rgb8UnormSrgb => Format::ETC2_R8G8B8_SRGB_BLOCK,
+        wgpu::TextureFormat::Etc2Rgb8A1Unorm => Format::ETC2_R8G8B8A1_UNORM_BLOCK,
+        wgpu::TextureFormat::Etc2Rgb8A1UnormSrgb => Format::ETC2_R8G8B8A1_SRGB_BLOCK,
+        wgpu::TextureFormat::Etc2Rgba8Unorm => Format::ETC2_R8G8B8A8_UNORM_BLOCK,
+        wgpu::TextureFormat::Etc2Rgba8UnormSrgb => Format::ETC2_R8G8B8A8_SRGB_BLOCK,
+        wgpu::TextureFormat::EacR11Unorm => Format::EAC_R11_UNORM_BLOCK,
+        wgpu::TextureFormat::EacR11Snorm => Format::EAC_R11_SNORM_BLOCK,
+        wgpu::TextureFormat::EacRg11Unorm => Format::EAC_R11G11_UNORM_BLOCK,
+        wgpu::TextureFormat::EacRg11Snorm => Format::EAC_R11G11_SNORM_BLOCK,
+        wgpu::TextureFormat::Astc { .. } => panic!("please god kill me now"),
+        _ => panic!("fuck no")
+    }
+}

src/input.rs

@@ -1,16 +1,18 @@
+use std::sync::Arc;
+
 use bevy::prelude::*;
 use openxr as xr;
 
 type XrPose = (Vec3, Quat);
 
-#[derive(Resource)]
+#[derive(Clone, Resource)]
 pub struct XrInput {
     action_set: xr::ActionSet,
     right_action: xr::Action<xr::Posef>,
     left_action: xr::Action<xr::Posef>,
-    right_space: xr::Space,
+    right_space: Arc<xr::Space>,
-    left_space: xr::Space,
+    left_space: Arc<xr::Space>,
-    stage: xr::Space,
+    pub stage: Arc<xr::Space>,
 }
 
 impl XrInput {
@@ -47,9 +49,9 @@ impl XrInput {
             action_set,
             right_action,
             left_action,
-            right_space,
+            right_space: Arc::new(right_space),
-            left_space,
+            left_space: Arc::new(left_space),
-            stage,
+            stage: Arc::new(stage),
         })
     }
 }

src/lib.rs

@@ -1,16 +1,23 @@
 pub mod input;
 pub mod resource_macros;
 pub mod resources;
+mod graphics;
 
 use std::sync::{Arc, Mutex};
 
 use bevy::ecs::system::SystemState;
 use bevy::prelude::*;
-use bevy::render::settings::WgpuSettings;
+use bevy::render::camera::{ManualTextureViews, ManualTextureView, ManualTextureViewHandle};
-use bevy::render::{FutureRendererResources, RenderPlugin, renderer};
+use bevy::render::{FutureRendererResources, RenderPlugin, RenderApp, Render, RenderSet};
 use bevy::window::{PrimaryWindow, RawHandleWrapper};
 use input::XrInput;
 use resources::*;
+use openxr as xr;
+
+const VIEW_TYPE: xr::ViewConfigurationType = xr::ViewConfigurationType::PRIMARY_STEREO;
+
+pub const LEFT_XR_TEXTURE_HANDLE: ManualTextureViewHandle = ManualTextureViewHandle(1208214591);
+pub const RIGHT_XR_TEXTURE_HANDLE: ManualTextureViewHandle = ManualTextureViewHandle(3383858418);
 
 /// Adds OpenXR support to an App
 #[derive(Default)]
@@ -28,6 +35,7 @@ pub struct FutureXrResources(
                 XrFrameWaiter,
                 XrSwapchain,
                 XrInput,
+                XrViews,
             )>,
         >,
     >,
@@ -49,38 +57,25 @@ impl Plugin for OpenXrPlugin {
             SystemState::new(&mut app.world);
         let primary_window = system_state.get(&app.world).get_single().ok().cloned();
 
-        let settings = WgpuSettings::default();
         bevy::tasks::IoTaskPool::get()
             .spawn_local(async move {
-                let instance = wgpu::Instance::new(wgpu::InstanceDescriptor {
+                let (device, queue, adapter_info, render_adapter, instance, xr_instance, session, blend_mode, session_running, frame_waiter, swapchain, input, views) = graphics::initialize_xr_graphics(primary_window).unwrap();
-                    backends: settings.backends.unwrap(),
-                    dx12_shader_compiler: settings.dx12_shader_compiler.clone(),
-                });
-                let surface = primary_window.map(|wrapper| unsafe {
-                    // SAFETY: Plugins should be set up on the main thread.
-                    let handle = wrapper.get_handle();
-                    instance
-                        .create_surface(&handle)
-                        .expect("Failed to create wgpu surface")
-                });
-
-                let request_adapter_options = wgpu::RequestAdapterOptions {
-                    power_preference: settings.power_preference,
-                    compatible_surface: surface.as_ref(),
-                    ..Default::default()
-                };
-
-                let (device, queue, adapter_info, render_adapter) =
-                    renderer::initialize_renderer(&instance, &settings, &request_adapter_options)
-                        .await;
                 debug!("Configured wgpu adapter Limits: {:#?}", device.limits());
                 debug!("Configured wgpu adapter Features: {:#?}", device.features());
                 let mut future_renderer_resources_inner =
                     future_renderer_resources_wrapper.lock().unwrap();
                 *future_renderer_resources_inner =
                     Some((device, queue, adapter_info, render_adapter, instance));
+                let mut future_xr_resources_inner = future_xr_resources_wrapper.lock().unwrap();
+                *future_xr_resources_inner =
+                    Some((xr_instance, session, blend_mode, session_running, frame_waiter, swapchain, input, views));
             })
             .detach();
+
+        app.add_systems(Last, pre_frame);
+
+        let render_app = app.sub_app_mut(RenderApp);
+        render_app.add_systems(Render, (post_frame.in_set(RenderSet::Prepare), post_queue_submit.in_set(RenderSet::Cleanup)));
     }
 
     fn ready(&self, app: &App) -> bool {
@@ -94,7 +89,7 @@ impl Plugin for OpenXrPlugin {
         if let Some(future_renderer_resources) =
             app.world.remove_resource::<FutureXrResources>()
         {
-            let (instance, session, blend_mode, session_running, frame_waiter, swapchain, input) =
+            let (instance, session, blend_mode, session_running, frame_waiter, swapchain, input, views) =
                 future_renderer_resources.0.lock().unwrap().take().unwrap();
 
             app.insert_resource(instance.clone())
@@ -102,7 +97,20 @@ impl Plugin for OpenXrPlugin {
                 .insert_resource(blend_mode.clone())
                 .insert_resource(session_running.clone())
                 .insert_resource(frame_waiter.clone())
-                .insert_resource(swapchain.clone());
+                .insert_resource(swapchain.clone())
+                .insert_resource(input.clone())
+                .insert_resource(views.clone());
+
+            let render_app = app.sub_app_mut(RenderApp);
+
+            render_app.insert_resource(instance)
+                .insert_resource(session)
+                .insert_resource(blend_mode)
+                .insert_resource(session_running)
+                .insert_resource(frame_waiter)
+                .insert_resource(swapchain)
+                .insert_resource(input)
+                .insert_resource(views);
         }
     }
 }
@@ -116,3 +124,87 @@ impl PluginGroup for DefaultXrPlugins {
             .add_before::<RenderPlugin, _>(OpenXrPlugin)
     }
 }
+
+pub fn pre_frame(
+    instance: Res<XrInstance>,
+    session: Res<XrSession>,
+    session_running: Res<XrSessionRunning>,
+    frame_state: Res<XrFrameState>,
+    frame_waiter: Res<XrFrameWaiter>,
+    swapchain: Res<XrSwapchain>,
+    mut manual_texture_views: ResMut<ManualTextureViews>,
+){
+    while let Some(event) = instance.poll_event(&mut Default::default()).unwrap() {
+        use xr::Event::*;
+        match event {
+            SessionStateChanged(e) => {
+                // Session state change is where we can begin and end sessions, as well as
+                // find quit messages!
+                info!("entered XR state {:?}", e.state());
+                match e.state() {
+                    xr::SessionState::READY => {
+                        session.begin(VIEW_TYPE).unwrap();
+                        session_running.store(true, std::sync::atomic::Ordering::Relaxed);
+                    }
+                    xr::SessionState::STOPPING => {
+                        session.end().unwrap();
+                        session_running.store(false, std::sync::atomic::Ordering::Relaxed);
+                    }
+                    xr::SessionState::EXITING | xr::SessionState::LOSS_PENDING => {
+                        return
+                    }
+                    _ => {}
+                }
+            }
+            InstanceLossPending(_) => {
+                return
+            }
+            EventsLost(e) => {
+                warn!("lost {} XR events", e.lost_event_count());
+            }
+            _ => {}
+        }
+    }
+    if !session_running.load(std::sync::atomic::Ordering::Relaxed) {
+        // Don't grind up the CPU
+        std::thread::sleep(std::time::Duration::from_millis(10));
+        return
+    }
+
+    *frame_state.lock().unwrap() = Some(frame_waiter.lock().unwrap().wait().unwrap());
+
+    let mut swapchain = swapchain.lock().unwrap();
+
+    swapchain.begin().unwrap();
+    let (left, right) = swapchain.get_render_views();
+    let left = ManualTextureView::with_default_format(left.into(), swapchain.resolution());
+    let right = ManualTextureView::with_default_format(right.into(), swapchain.resolution());
+    manual_texture_views.insert(LEFT_XR_TEXTURE_HANDLE, left);
+    manual_texture_views.insert(RIGHT_XR_TEXTURE_HANDLE, right);
+}
+
+pub fn post_frame(
+    views: Res<XrViews>,
+    input: Res<XrInput>,
+    session: Res<XrSession>,
+    xr_frame_state: Res<XrFrameState>,
+) {
+    *views.lock().unwrap() = session.locate_views(
+        VIEW_TYPE,
+        xr_frame_state.lock().unwrap().unwrap().predicted_display_time,
+        &input.stage,
+    ).unwrap().1;
+}
+
+pub fn post_queue_submit(
+    xr_frame_state: Res<XrFrameState>,
+    views: Res<XrViews>,
+    input: Res<XrInput>,
+    swapchain: Res<XrSwapchain>,
+    environment_blend_mode: Res<XrEnvironmentBlendMode>,
+) {
+    let xr_frame_state = xr_frame_state.lock().unwrap().unwrap();
+    let views = &*views.lock().unwrap();
+    let stage = &input.stage;
+    swapchain.lock().unwrap().post_queue_submit(xr_frame_state, views, stage, **environment_blend_mode).unwrap();
+}

src/resources.rs

@@ -1,23 +1,127 @@
-use std::sync::Mutex;
 use std::sync::atomic::AtomicBool;
+use std::sync::Mutex;
 
 use crate::resource_macros::*;
+use bevy::prelude::*;
 use openxr as xr;
 
 xr_resource_wrapper!(XrInstance, xr::Instance);
 xr_resource_wrapper!(XrSession, xr::Session<xr::AnyGraphics>);
 xr_resource_wrapper!(XrEnvironmentBlendMode, xr::EnvironmentBlendMode);
+xr_resource_wrapper!(XrViewConfigurationViews, Vec<xr::ViewConfigurationView>);
 xr_arc_resource_wrapper!(XrSessionRunning, AtomicBool);
-xr_arc_resource_wrapper!(XrFrameWaiter, Mutex<XrFrameWaiter>);
+xr_arc_resource_wrapper!(XrFrameWaiter, Mutex<xr::FrameWaiter>);
 xr_arc_resource_wrapper!(XrSwapchain, Mutex<Swapchain>);
+xr_arc_resource_wrapper!(XrFrameState, Mutex<Option<xr::FrameState>>);
+xr_arc_resource_wrapper!(XrViews, Mutex<Vec<xr::View>>);
 
 pub enum Swapchain {
-    Vulkan(SwapchainInner<xr::Vulkan>)
+    Vulkan(SwapchainInner<xr::Vulkan>),
+}
+
+impl Swapchain {
+    pub(crate) fn begin(&mut self) -> xr::Result<()> {
+        match self {
+            Swapchain::Vulkan(swap) => swap.begin(),
+        }
+    }
+
+    pub(crate) fn get_render_views(&mut self) -> (wgpu::TextureView, wgpu::TextureView) {
+        match self {
+            Swapchain::Vulkan(swap) => swap.get_render_views(),
+        }
+    }
+
+    pub(crate) fn resolution(&self) -> UVec2 {
+        match self {
+            Swapchain::Vulkan(swap) => swap.resolution,
+        }
+    }
+
+    pub(crate) fn post_queue_submit(
+        &mut self,
+        xr_frame_state: xr::FrameState,
+        views: &[openxr::View],
+        stage: &xr::Space,
+        environment_blend_mode: xr::EnvironmentBlendMode,
+    ) -> xr::Result<()> {
+        match self {
+            Swapchain::Vulkan(swap) => swap.post_queue_submit(xr_frame_state, views, stage, environment_blend_mode),
+        }
+    }
 }
 
 pub struct SwapchainInner<G: xr::Graphics> {
-    stream: xr::FrameStream<G>,
+    pub(crate) stream: xr::FrameStream<G>,
-    handle: xr::Swapchain<G>,
+    pub(crate) handle: xr::Swapchain<G>,
-    resolution: (u32, u32),
+    pub(crate) resolution: UVec2,
-    buffers: Vec<wgpu::Texture>,
+    pub(crate) buffers: Vec<wgpu::Texture>,
+}
+
+impl<G: xr::Graphics> SwapchainInner<G> {
+    fn begin(&mut self) -> xr::Result<()> {
+        self.stream.begin()
+    }
+
+    fn get_render_views(&mut self) -> (wgpu::TextureView, wgpu::TextureView) {
+        let image_index = self.handle.acquire_image().unwrap();
+        self.handle.wait_image(xr::Duration::INFINITE).unwrap();
+
+        let texture = &self.buffers[image_index as usize];
+
+        (
+            texture.create_view(&wgpu::TextureViewDescriptor {
+                dimension: Some(wgpu::TextureViewDimension::D2),
+                array_layer_count: Some(1),
+                ..Default::default()
+            }),
+            texture.create_view(&wgpu::TextureViewDescriptor {
+                dimension: Some(wgpu::TextureViewDimension::D2),
+                array_layer_count: Some(1),
+                base_array_layer: 1,
+                ..Default::default()
+            }),
+        )
+    }
+
+    fn post_queue_submit(
+        &mut self,
+        xr_frame_state: xr::FrameState,
+        views: &[openxr::View],
+        stage: &xr::Space,
+        environment_blend_mode: xr::EnvironmentBlendMode,
+    ) -> xr::Result<()> {
+        self.handle.release_image().unwrap();
+            let rect = xr::Rect2Di {
+                offset: xr::Offset2Di { x: 0, y: 0 },
+                extent: xr::Extent2Di {
+                    width: self.resolution.x as _,
+                    height: self.resolution.y as _,
+                },
+            };
+            self.stream.end(
+                xr_frame_state.predicted_display_time,
+                environment_blend_mode,
+                &[&xr::CompositionLayerProjection::new().space(stage).views(&[
+                    xr::CompositionLayerProjectionView::new()
+                        .pose(views[0].pose)
+                        .fov(views[0].fov)
+                        .sub_image(
+                            xr::SwapchainSubImage::new()
+                                .swapchain(&self.handle)
+                                .image_array_index(0)
+                                .image_rect(rect),
+                        ),
+                    xr::CompositionLayerProjectionView::new()
+                        .pose(views[1].pose)
+                        .fov(views[1].fov)
+                        .sub_image(
+                            xr::SwapchainSubImage::new()
+                                .swapchain(&self.handle)
+                                .image_array_index(1)
+                                .image_rect(rect),
+                        ),
+                ])],
+            )
+    }
 }