Files
test2/source/blender/gpu/vulkan/vk_context.cc
Jeroen Bakker 3885a37541 Vulkan: Initial OpenXR support
The Blender's VkInstance cannot be shared with OpenXR VkInstance. The
reason is a chicken and egg problem where OpenXR needs to be started
before Vulkan. OpenXR can add special vulkan specific requirements
(instance&device) that are only available when the user starts an OpenXR
session.

The goal implementation is to share memory between both instances using
[VK_KHR_external_memory](https://registry.khronos.org/vulkan/specs/latest/man/html/VK_KHR_external_memory.html) and related extensions. However this seems
to be a bridge to far as a initial step. Reason: There are not that many
samples/ guides and documentation to be found to handle the workflow that
we require. We want to do a smaller step by step approach to gain the needed
knowledge.

For that reason this PR does the most stupidest thing that can be done to
share memory between instances. Download the render result to CPU RAM share
the host pointer with the OpenXR instance which copies it to the swap chain.
Also the synchronization is done using wait idle commands.

<video src="attachments/32a0d69b-c3fa-4272-aea0-d207609afaaf" title="Screencast From 2025-03-18 11-16-17.webm" controls></video>

**Gaining knowledge**

- Experiment with `VK_KHR_external_memory_host` extension for uploading vertex buffers (not related to OpenXR).
- Import host pointer with `VK_KHR_external_memory_host`. This reduces the additional
  memcpy on OpenXR side.
- Export host pointer from Blender side from a mappable buffer.
- Replace host pointers with fd/dmabuf/winhandle
- Remove mappable buffer.

Ref #133718

Pull Request: https://projects.blender.org/blender/blender/pulls/133824
2025-03-27 16:57:51 +01:00

440 lines
13 KiB
C++

/* SPDX-FileCopyrightText: 2022 Blender Authors
*
* SPDX-License-Identifier: GPL-2.0-or-later */
/** \file
* \ingroup gpu
*/
#include "GPU_debug.hh"
#include "vk_backend.hh"
#include "vk_context.hh"
#include "vk_debug.hh"
#include "vk_framebuffer.hh"
#include "vk_immediate.hh"
#include "vk_shader.hh"
#include "vk_shader_interface.hh"
#include "vk_state_manager.hh"
#include "vk_texture.hh"
#include "GHOST_C-api.h"
namespace blender::gpu {
VKContext::VKContext(void *ghost_window, void *ghost_context)
{
ghost_window_ = ghost_window;
ghost_context_ = ghost_context;
state_manager = new VKStateManager();
back_left = new VKFrameBuffer("back_left");
front_left = new VKFrameBuffer("front_left");
active_fb = back_left;
compiler = &VKBackend::get().shader_compiler;
}
VKContext::~VKContext()
{
if (surface_texture_) {
back_left->attachment_remove(GPU_FB_COLOR_ATTACHMENT0);
front_left->attachment_remove(GPU_FB_COLOR_ATTACHMENT0);
GPU_texture_free(surface_texture_);
surface_texture_ = nullptr;
}
free_resources();
VKBackend::get().device.context_unregister(*this);
imm = nullptr;
compiler = nullptr;
}
void VKContext::sync_backbuffer(bool cycle_resource_pool)
{
if (ghost_window_) {
GHOST_VulkanSwapChainData swap_chain_data = {};
GHOST_GetVulkanSwapChainFormat((GHOST_WindowHandle)ghost_window_, &swap_chain_data);
VKThreadData &thread_data = thread_data_.value().get();
if (cycle_resource_pool) {
thread_data.resource_pool_next();
VKResourcePool &resource_pool = thread_data.resource_pool_get();
imm = &resource_pool.immediate;
}
const bool reset_framebuffer = swap_chain_format_.format !=
swap_chain_data.surface_format.format ||
swap_chain_format_.colorSpace !=
swap_chain_data.surface_format.colorSpace ||
vk_extent_.width != swap_chain_data.extent.width ||
vk_extent_.height != swap_chain_data.extent.height;
if (reset_framebuffer) {
if (has_active_framebuffer()) {
deactivate_framebuffer();
}
if (surface_texture_) {
GPU_texture_free(surface_texture_);
surface_texture_ = nullptr;
}
surface_texture_ = GPU_texture_create_2d(
"back-left",
swap_chain_data.extent.width,
swap_chain_data.extent.height,
1,
to_gpu_format(swap_chain_data.surface_format.format),
GPU_TEXTURE_USAGE_ATTACHMENT,
nullptr);
back_left->attachment_set(GPU_FB_COLOR_ATTACHMENT0,
GPU_ATTACHMENT_TEXTURE(surface_texture_));
front_left->attachment_set(GPU_FB_COLOR_ATTACHMENT0,
GPU_ATTACHMENT_TEXTURE(surface_texture_));
back_left->bind(false);
swap_chain_format_ = swap_chain_data.surface_format;
vk_extent_ = swap_chain_data.extent;
}
}
}
void VKContext::activate()
{
/* Make sure no other context is already bound to this thread. */
BLI_assert(is_active_ == false);
VKDevice &device = VKBackend::get().device;
VKThreadData &thread_data = device.current_thread_data();
thread_data_ = std::reference_wrapper<VKThreadData>(thread_data);
if (!render_graph_.has_value()) {
render_graph_ = std::reference_wrapper<render_graph::VKRenderGraph>(
*device.render_graph_new());
for (const StringRef &group : debug_stack) {
debug_group_begin(std::string(group).c_str(), 0);
}
}
imm = &thread_data.resource_pool_get().immediate;
is_active_ = true;
sync_backbuffer(false);
immActivate();
}
void VKContext::deactivate()
{
flush_render_graph(RenderGraphFlushFlags(0));
immDeactivate();
imm = nullptr;
thread_data_.reset();
is_active_ = false;
}
void VKContext::begin_frame() {}
void VKContext::end_frame()
{
VKDevice &device = VKBackend::get().device;
device.orphaned_data.destroy_discarded_resources(device);
}
void VKContext::flush() {}
TimelineValue VKContext::flush_render_graph(RenderGraphFlushFlags flags,
VkPipelineStageFlags wait_dst_stage_mask,
VkSemaphore wait_semaphore,
VkSemaphore signal_semaphore)
{
if (has_active_framebuffer()) {
VKFrameBuffer &framebuffer = *active_framebuffer_get();
if (framebuffer.is_rendering()) {
framebuffer.rendering_end(*this);
}
}
descriptor_set_get().upload_descriptor_sets();
VKDevice &device = VKBackend::get().device;
TimelineValue timeline = device.render_graph_submit(
&render_graph_.value().get(),
discard_pool,
bool(flags & RenderGraphFlushFlags::SUBMIT),
bool(flags & RenderGraphFlushFlags::WAIT_FOR_COMPLETION),
wait_dst_stage_mask,
wait_semaphore,
signal_semaphore);
render_graph_.reset();
if (bool(flags & RenderGraphFlushFlags::RENEW_RENDER_GRAPH)) {
render_graph_ = std::reference_wrapper<render_graph::VKRenderGraph>(
*device.render_graph_new());
for (const StringRef &group : debug_stack) {
debug_group_begin(std::string(group).c_str(), 0);
}
}
return timeline;
}
void VKContext::finish() {}
void VKContext::memory_statistics_get(int *r_total_mem_kb, int *r_free_mem_kb)
{
const VKDevice &device = VKBackend::get().device;
device.memory_statistics_get(r_total_mem_kb, r_free_mem_kb);
}
/* -------------------------------------------------------------------- */
/** \name State manager
* \{ */
VKDescriptorPools &VKContext::descriptor_pools_get()
{
return thread_data_.value().get().resource_pool_get().descriptor_pools;
}
VKDescriptorSetTracker &VKContext::descriptor_set_get()
{
return thread_data_.value().get().resource_pool_get().descriptor_set;
}
VKStateManager &VKContext::state_manager_get() const
{
return *static_cast<VKStateManager *>(state_manager);
}
void VKContext::debug_unbind_all_ubo()
{
state_manager_get().uniform_buffer_unbind_all();
};
void VKContext::debug_unbind_all_ssbo()
{
state_manager_get().storage_buffer_unbind_all();
};
/** \} */
/* -------------------------------------------------------------------- */
/** \name Frame-buffer
* \{ */
void VKContext::activate_framebuffer(VKFrameBuffer &framebuffer)
{
if (has_active_framebuffer()) {
deactivate_framebuffer();
}
BLI_assert(active_fb == nullptr);
active_fb = &framebuffer;
framebuffer.update_size();
framebuffer.update_srgb();
framebuffer.rendering_reset();
}
VKFrameBuffer *VKContext::active_framebuffer_get() const
{
return unwrap(active_fb);
}
bool VKContext::has_active_framebuffer() const
{
return active_framebuffer_get() != nullptr;
}
void VKContext::deactivate_framebuffer()
{
VKFrameBuffer *framebuffer = active_framebuffer_get();
BLI_assert(framebuffer != nullptr);
if (framebuffer->is_rendering()) {
framebuffer->rendering_end(*this);
}
active_fb = nullptr;
}
void VKContext::rendering_end()
{
VKFrameBuffer *framebuffer = active_framebuffer_get();
if (framebuffer) {
framebuffer->rendering_end(*this);
}
}
/** \} */
/* -------------------------------------------------------------------- */
/** \name Pipeline
* \{ */
void VKContext::update_pipeline_data(GPUPrimType primitive,
VKVertexAttributeObject &vao,
render_graph::VKPipelineData &r_pipeline_data)
{
VKShader &vk_shader = unwrap(*shader);
VKFrameBuffer &framebuffer = *active_framebuffer_get();
update_pipeline_data(
vk_shader,
vk_shader.ensure_and_get_graphics_pipeline(primitive, vao, state_manager_get(), framebuffer),
r_pipeline_data);
}
void VKContext::update_pipeline_data(render_graph::VKPipelineData &r_pipeline_data)
{
VKShader &vk_shader = unwrap(*shader);
update_pipeline_data(vk_shader, vk_shader.ensure_and_get_compute_pipeline(), r_pipeline_data);
}
void VKContext::update_pipeline_data(VKShader &vk_shader,
VkPipeline vk_pipeline,
render_graph::VKPipelineData &r_pipeline_data)
{
r_pipeline_data.vk_pipeline_layout = vk_shader.vk_pipeline_layout;
r_pipeline_data.vk_pipeline = vk_pipeline;
/* Update push constants. */
r_pipeline_data.push_constants_data = nullptr;
r_pipeline_data.push_constants_size = 0;
const VKPushConstants::Layout &push_constants_layout =
vk_shader.interface_get().push_constants_layout_get();
if (push_constants_layout.storage_type_get() == VKPushConstants::StorageType::PUSH_CONSTANTS) {
r_pipeline_data.push_constants_size = push_constants_layout.size_in_bytes();
r_pipeline_data.push_constants_data = vk_shader.push_constants.data();
}
/* Update descriptor set. */
r_pipeline_data.vk_descriptor_set = VK_NULL_HANDLE;
if (vk_shader.has_descriptor_set()) {
VKDescriptorSetTracker &descriptor_set = descriptor_set_get();
descriptor_set.update_descriptor_set(*this, access_info_);
r_pipeline_data.vk_descriptor_set = descriptor_set.vk_descriptor_set;
}
}
render_graph::VKResourceAccessInfo &VKContext::reset_and_get_access_info()
{
access_info_.reset();
return access_info_;
}
/** \} */
/* -------------------------------------------------------------------- */
/** \name Graphics pipeline
* \{ */
void VKContext::swap_buffers_pre_callback(const GHOST_VulkanSwapChainData *swap_chain_data)
{
VKContext *context = VKContext::get();
BLI_assert(context);
context->swap_buffers_pre_handler(*swap_chain_data);
}
void VKContext::swap_buffers_post_callback()
{
VKContext *context = VKContext::get();
BLI_assert(context);
context->swap_buffers_post_handler();
}
void VKContext::swap_buffers_pre_handler(const GHOST_VulkanSwapChainData &swap_chain_data)
{
GPU_debug_group_begin("BackBuffer.Blit");
VKFrameBuffer &framebuffer = *unwrap(active_fb);
VKTexture *color_attachment = unwrap(unwrap(framebuffer.color_tex(0)));
render_graph::VKBlitImageNode::CreateInfo blit_image = {};
blit_image.src_image = color_attachment->vk_image_handle();
blit_image.dst_image = swap_chain_data.image;
blit_image.filter = VK_FILTER_NEAREST;
VkImageBlit &region = blit_image.region;
region.srcOffsets[0] = {0, color_attachment->height_get(), 0};
region.srcOffsets[1] = {color_attachment->width_get(), 0, 1};
region.srcSubresource.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
region.srcSubresource.mipLevel = 0;
region.srcSubresource.baseArrayLayer = 0;
region.srcSubresource.layerCount = 1;
region.dstOffsets[0] = {0, 0, 0};
region.dstOffsets[1] = {
int32_t(swap_chain_data.extent.width), int32_t(swap_chain_data.extent.height), 1};
region.dstSubresource.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
region.dstSubresource.mipLevel = 0;
region.dstSubresource.baseArrayLayer = 0;
region.dstSubresource.layerCount = 1;
/* Swap chain commands are CPU synchronized at this moment, allowing to temporary add the swap
* chain image as device resources. When we move towards GPU swap chain synchronization we need
* to keep track of the swap chain image between frames. */
VKDevice &device = VKBackend::get().device;
device.resources.add_image(swap_chain_data.image, 1, "SwapchainImage");
framebuffer.rendering_end(*this);
flush_render_graph(RenderGraphFlushFlags::RENEW_RENDER_GRAPH);
render_graph::VKRenderGraph &render_graph = this->render_graph();
render_graph.add_node(blit_image);
GPU_debug_group_end();
descriptor_set_get().upload_descriptor_sets();
render_graph::VKSynchronizationNode::CreateInfo synchronization = {};
synchronization.vk_image = swap_chain_data.image;
synchronization.vk_image_layout = VK_IMAGE_LAYOUT_PRESENT_SRC_KHR;
synchronization.vk_image_aspect = VK_IMAGE_ASPECT_COLOR_BIT;
render_graph.add_node(synchronization);
flush_render_graph(RenderGraphFlushFlags::SUBMIT | RenderGraphFlushFlags::RENEW_RENDER_GRAPH,
VK_PIPELINE_STAGE_COMPUTE_SHADER_BIT | VK_PIPELINE_STAGE_TRANSFER_BIT,
swap_chain_data.acquire_semaphore,
swap_chain_data.present_semaphore);
device.resources.remove_image(swap_chain_data.image);
#if 0
device.debug_print();
#endif
}
void VKContext::swap_buffers_post_handler()
{
sync_backbuffer(true);
}
/** \} */
/* -------------------------------------------------------------------- */
/** \name OpenXR
* \{ */
void VKContext::openxr_acquire_framebuffer_image_callback(GHOST_VulkanOpenXRData *openxr_data)
{
VKContext *context = VKContext::get();
BLI_assert(context);
context->openxr_acquire_framebuffer_image_handler(*openxr_data);
}
void VKContext::openxr_release_framebuffer_image_callback(GHOST_VulkanOpenXRData *openxr_data)
{
VKContext *context = VKContext::get();
BLI_assert(context);
context->openxr_release_framebuffer_image_handler(*openxr_data);
}
void VKContext::openxr_acquire_framebuffer_image_handler(GHOST_VulkanOpenXRData &openxr_data)
{
VKFrameBuffer &framebuffer = *unwrap(active_fb);
VKTexture *color_attachment = unwrap(unwrap(framebuffer.color_tex(0)));
openxr_data.image_data = color_attachment->read(0, GPU_DATA_HALF_FLOAT);
openxr_data.extent.width = color_attachment->width_get();
openxr_data.extent.height = color_attachment->height_get();
}
void VKContext::openxr_release_framebuffer_image_handler(GHOST_VulkanOpenXRData &openxr_data)
{
MEM_freeN(openxr_data.image_data);
openxr_data.image_data = nullptr;
}
/** \} */
} // namespace blender::gpu