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Class ILLIXR::stereo_renderer

ClassList > ILLIXR > stereo_renderer

Stereo video renderer for Quest 3 — Vulkan backend. More...

  • #include <stereo_renderer.hpp>

Public Functions

Type Name
void cleanup ()
bool has_frame () const
bool initialize (VkInstance instance, VkPhysicalDevice physical_device, VkDevice device, VkQueue queue, uint32_t queue_family, VkFormat swapchain_format)
Initialize Vulkan rendering resources.
bool is_initialized () const
stereo_renderer & operator= (const stereo_renderer &) = delete
void receive_frame (const data_format::dual_frames & frame)
Import AHardwareBuffer handles from a decoded frame into Vulkan.
bool render_eye (int eye, VkImage swapchain_image, uint32_t swapchain_width, uint32_t swapchain_height, VkSemaphore signal_semaphore=VK_NULL_HANDLE)
Record and submit a command buffer that renders one eye's color.
bool render_eye_depth (int eye, VkImage depth_swapchain_image, VkFormat depth_format, uint32_t swapchain_width, uint32_t swapchain_height)
Record and submit a command buffer that renders one eye's depth.
bool render_eye_motion_vec (int eye, VkImage mv_swapchain_image, uint32_t swapchain_width, uint32_t swapchain_height)
Record and submit a command buffer that renders one eye's motion-vector data into an App Spacewarp swapchain image.
void set_crop_region (int original_width, int original_height, int padded_width, int padded_height)
stereo_renderer () = default
stereo_renderer (const stereo_renderer &) = delete
void wait_idle ()
Wait for all in-flight rendering to complete.
~stereo_renderer ()

Detailed Description

Replaces the previous OpenGL ES / SurfaceTexture path entirely. No EGL context is needed; this class operates purely on Vulkan objects.

Typical per-frame usage (called from the render thread in oxr_interface):

renderer_->receive_frame(frame); // import AHardwareBuffers for (int eye = 0; eye < 2; eye++) { renderer_->render_eye(eye, // record + submit command buffer swapchain_image, swapchain_width, swapchain_height, signal_semaphore);

if (frame.has_valid_depth()) { renderer_->render_eye_depth(eye, ...); // depth swapchain image }

if (frame.has_valid_motion_vectors()) { renderer_->render_eye_motion_vec(eye, …); // spacewarp MV swapchain } }

Public Functions Documentation

function cleanup

void ILLIXR::stereo_renderer::cleanup ()

function has_frame

inline bool ILLIXR::stereo_renderer::has_frame () const

function initialize

Initialize Vulkan rendering resources. 

bool ILLIXR::stereo_renderer::initialize (
    VkInstance instance,
    VkPhysicalDevice physical_device,
    VkDevice device,
    VkQueue queue,
    uint32_t queue_family,
    VkFormat swapchain_format
)

Must be called once after the OpenXR Vulkan session has been created.

Parameters:

  • instance Vulkan instance (created via xrCreateVulkanInstanceKHR).
  • physical_device Physical device selected by OpenXR.
  • device Logical device (created via xrCreateVulkanDeviceKHR).
  • queue Graphics queue used for rendering submissions.
  • queue_family Queue family index for the graphics queue.
  • swapchain_format VkFormat of the OpenXR swapchain images.

Returns:

true on success.

function is_initialized

inline bool ILLIXR::stereo_renderer::is_initialized () const

function operator=

stereo_renderer & ILLIXR::stereo_renderer::operator= (
    const  stereo_renderer &
) = delete

function receive_frame

Import AHardwareBuffer handles from a decoded frame into Vulkan. 

void ILLIXR::stereo_renderer::receive_frame (
    const  data_format::dual_frames & frame
)

Call this once per frame before any render_eye* calls. For hardware_buffer format: caches imported images keyed by buffer pointer. For nv12 format: uploads pixel data to internal textures.

function render_eye

Record and submit a command buffer that renders one eye's color. 

bool ILLIXR::stereo_renderer::render_eye (
    int eye,
    VkImage swapchain_image,
    uint32_t swapchain_width,
    uint32_t swapchain_height,
    VkSemaphore signal_semaphore=VK_NULL_HANDLE
)

Parameters:

  • eye 0 = left, 1 = right.
  • swapchain_image The VkImage from xrAcquireSwapchainImage.
  • swapchain_width Swapchain image width.
  • swapchain_height Swapchain image height.
  • signal_semaphore VkSemaphore to signal when GPU work is complete (pass VK_NULL_HANDLE if not needed).

Returns:

true on success.

function render_eye_depth

Record and submit a command buffer that renders one eye's depth. 

bool ILLIXR::stereo_renderer::render_eye_depth (
    int eye,
    VkImage depth_swapchain_image,
    VkFormat depth_format,
    uint32_t swapchain_width,
    uint32_t swapchain_height
)

Samples the decoded depth AHardwareBuffer (RG-packed 16-bit depth) and writes the reconstructed normalised depth values into the OpenXR depth swapchain image. Must only be called when has_frame() is true and the frame has has_valid_depth() == true.

Parameters:

  • eye 0 = left, 1 = right.
  • depth_swapchain_image The VkImage from the depth XrSwapchain.
  • depth_format VkFormat of the depth swapchain (e.g. VK_FORMAT_D32_SFLOAT).
  • swapchain_width Image width.
  • swapchain_height Image height.

Returns:

true on success.

function render_eye_motion_vec

Record and submit a command buffer that renders one eye's motion-vector data into an App Spacewarp swapchain image. 

bool ILLIXR::stereo_renderer::render_eye_motion_vec (
    int eye,
    VkImage mv_swapchain_image,
    uint32_t swapchain_width,
    uint32_t swapchain_height
)

Samples the decoded motion-vector AHardwareBuffer (HEVC 10-bit, two-component screen-space motion packed into Y/Cb planes) and converts it to VK_FORMAT_R16G16B16A16_SFLOAT for submission via XrCompositionLayerSpaceWarpInfoFB::motionVectorSubImage.

Must only be called when has_frame() is true and the frame has has_valid_motion_vectors() == true.

Parameters:

  • eye 0 = left, 1 = right.
  • mv_swapchain_image The VkImage from the motion-vector XrSwapchain.
  • swapchain_width Image width (typically 432).
  • swapchain_height Image height (typically 432).

Returns:

true on success.

function set_crop_region

void ILLIXR::stereo_renderer::set_crop_region (
    int original_width,
    int original_height,
    int padded_width,
    int padded_height
)

function stereo_renderer [1/2]

ILLIXR::stereo_renderer::stereo_renderer () = default

function stereo_renderer [2/2]

ILLIXR::stereo_renderer::stereo_renderer (
    const  stereo_renderer &
) = delete

function wait_idle

Wait for all in-flight rendering to complete. 

void ILLIXR::stereo_renderer::wait_idle ()

Call before releasing AHardwareBuffers from the previous frame.

function ~stereo_renderer

ILLIXR::stereo_renderer::~stereo_renderer ()

The documentation for this class was generated from the following file /home/friedel/devel/ILLIXR/illixr_release/ILLIXR/plugins/openxr_interface/stereo_renderer.hpp