mirror of
https://github.com/vulkano-rs/vulkano.git
synced 2024-11-25 16:25:31 +00:00
289ec102e0
* Document shader safety requirements, make draw/dispatch unsafe * Extra docs * Doctests * Max index value * Small change * Update vulkano/src/command_buffer/mod.rs Co-authored-by: marc0246 <40955683+marc0246@users.noreply.github.com> * Update vulkano/src/command_buffer/mod.rs Co-authored-by: marc0246 <40955683+marc0246@users.noreply.github.com> --------- Co-authored-by: marc0246 <40955683+marc0246@users.noreply.github.com>
895 lines
35 KiB
Rust
895 lines
35 KiB
Rust
// This example showcases how you can most effectively update a resource asynchronously, such that
|
|
// your rendering or any other tasks can use the resource without any latency at the same time as
|
|
// it's being updated.
|
|
//
|
|
// There are two kinds of resources that are updated asynchronously here:
|
|
//
|
|
// - A uniform buffer, which needs to be updated every frame.
|
|
// - A large texture, which needs to be updated partially at the request of the user.
|
|
//
|
|
// For the first, since the data needs to be updated every frame, we have to use one buffer per
|
|
// frame in flight. The swapchain most commonly has multiple images that are all processed at the
|
|
// same time, therefore writing the same buffer during each frame in flight would result in one of
|
|
// two things: either you would have to synchronize the writes from the host and reads from the
|
|
// device such that only one of the images in the swapchain is actually processed at any point in
|
|
// time (bad), or a race condition (bad). Therefore we are left with no choice but to use a
|
|
// different buffer for each frame in flight. This is best suited to very small pieces of data that
|
|
// change rapidly, and where the data of one frame doesn't depend on data from a previous one.
|
|
//
|
|
// For the second, since this texture is rather large, we can't afford to overwrite the entire
|
|
// texture every time a part of it needs to be updated. Also, we don't need as many textures as
|
|
// there are frames in flight since the texture doesn't need to be updated every frame, but we
|
|
// still need at least two textures. That way we can write one of the textures at the same time as
|
|
// reading the other, swapping them after the write is done such that the newly updated one is read
|
|
// and the now out-of-date one can be written to next time, known as *eventual consistency*.
|
|
//
|
|
// In an eventually consistent system, a number of *replicas* are used, all of which represent the
|
|
// same data but their consistency is not strict. A replica might be out-of-date for some time
|
|
// before *reaching convergence*, hence becoming consistent, eventually.
|
|
|
|
use cgmath::{Matrix4, Rad};
|
|
use rand::Rng;
|
|
use std::{
|
|
error::Error,
|
|
hint,
|
|
sync::{
|
|
atomic::{AtomicBool, AtomicU64, Ordering},
|
|
mpsc, Arc,
|
|
},
|
|
thread,
|
|
time::{SystemTime, UNIX_EPOCH},
|
|
};
|
|
use vulkano::{
|
|
buffer::{Buffer, BufferContents, BufferCreateInfo, BufferUsage},
|
|
command_buffer::{
|
|
allocator::StandardCommandBufferAllocator, BufferImageCopy, ClearColorImageInfo,
|
|
CommandBufferBeginInfo, CommandBufferLevel, CommandBufferUsage, CopyBufferToImageInfo,
|
|
RecordingCommandBuffer, RenderPassBeginInfo,
|
|
},
|
|
descriptor_set::{
|
|
allocator::StandardDescriptorSetAllocator, DescriptorSet, WriteDescriptorSet,
|
|
},
|
|
device::{
|
|
physical::PhysicalDeviceType, Device, DeviceCreateInfo, DeviceExtensions, Queue,
|
|
QueueCreateInfo, QueueFlags,
|
|
},
|
|
format::Format,
|
|
image::{
|
|
sampler::{Sampler, SamplerCreateInfo},
|
|
view::ImageView,
|
|
Image, ImageCreateInfo, ImageType, ImageUsage,
|
|
},
|
|
instance::{Instance, InstanceCreateFlags, InstanceCreateInfo},
|
|
memory::allocator::{AllocationCreateInfo, MemoryTypeFilter, StandardMemoryAllocator},
|
|
pipeline::{
|
|
graphics::{
|
|
color_blend::{ColorBlendAttachmentState, ColorBlendState},
|
|
input_assembly::{InputAssemblyState, PrimitiveTopology},
|
|
multisample::MultisampleState,
|
|
rasterization::RasterizationState,
|
|
vertex_input::{Vertex, VertexDefinition},
|
|
viewport::{Viewport, ViewportState},
|
|
GraphicsPipelineCreateInfo,
|
|
},
|
|
layout::PipelineDescriptorSetLayoutCreateInfo,
|
|
DynamicState, GraphicsPipeline, Pipeline, PipelineBindPoint, PipelineLayout,
|
|
PipelineShaderStageCreateInfo,
|
|
},
|
|
render_pass::{Framebuffer, FramebufferCreateInfo, RenderPass, Subpass},
|
|
swapchain::{
|
|
acquire_next_image, Surface, Swapchain, SwapchainCreateInfo, SwapchainPresentInfo,
|
|
},
|
|
sync::{self, GpuFuture},
|
|
Validated, VulkanError, VulkanLibrary,
|
|
};
|
|
use winit::{
|
|
event::{ElementState, Event, KeyEvent, WindowEvent},
|
|
event_loop::{ControlFlow, EventLoop},
|
|
keyboard::{Key, NamedKey},
|
|
window::WindowBuilder,
|
|
};
|
|
|
|
const TRANSFER_GRANULARITY: u32 = 4096;
|
|
|
|
fn main() -> Result<(), impl Error> {
|
|
let event_loop = EventLoop::new().unwrap();
|
|
|
|
let library = VulkanLibrary::new().unwrap();
|
|
let required_extensions = Surface::required_extensions(&event_loop).unwrap();
|
|
let instance = Instance::new(
|
|
library,
|
|
InstanceCreateInfo {
|
|
flags: InstanceCreateFlags::ENUMERATE_PORTABILITY,
|
|
enabled_extensions: required_extensions,
|
|
..Default::default()
|
|
},
|
|
)
|
|
.unwrap();
|
|
|
|
let window = Arc::new(WindowBuilder::new().build(&event_loop).unwrap());
|
|
let surface = Surface::from_window(instance.clone(), window.clone()).unwrap();
|
|
|
|
let device_extensions = DeviceExtensions {
|
|
khr_swapchain: true,
|
|
..DeviceExtensions::empty()
|
|
};
|
|
let (physical_device, graphics_family_index) = instance
|
|
.enumerate_physical_devices()
|
|
.unwrap()
|
|
.filter(|p| p.supported_extensions().contains(&device_extensions))
|
|
.filter_map(|p| {
|
|
p.queue_family_properties()
|
|
.iter()
|
|
.enumerate()
|
|
.position(|(i, q)| {
|
|
q.queue_flags.intersects(QueueFlags::GRAPHICS)
|
|
&& p.surface_support(i as u32, &surface).unwrap_or(false)
|
|
})
|
|
.map(|i| (p, i as u32))
|
|
})
|
|
.min_by_key(|(p, _)| match p.properties().device_type {
|
|
PhysicalDeviceType::DiscreteGpu => 0,
|
|
PhysicalDeviceType::IntegratedGpu => 1,
|
|
PhysicalDeviceType::VirtualGpu => 2,
|
|
PhysicalDeviceType::Cpu => 3,
|
|
PhysicalDeviceType::Other => 4,
|
|
_ => 5,
|
|
})
|
|
.unwrap();
|
|
|
|
println!(
|
|
"Using device: {} (type: {:?})",
|
|
physical_device.properties().device_name,
|
|
physical_device.properties().device_type,
|
|
);
|
|
|
|
// Since we are going to be updating the texture on a separate thread asynchronously from the
|
|
// execution of graphics commands, it would make sense to also do the transfer on a dedicated
|
|
// transfer queue, if such a queue family exists. That way, the graphics queue is not blocked
|
|
// during the transfers either and the two tasks are truly asynchronous.
|
|
//
|
|
// For this, we need to find the queue family with the fewest queue flags set, since if the
|
|
// queue fmaily has more flags than `TRANSFER | SPARSE_BINDING`, that means it is not dedicated
|
|
// to transfer operations.
|
|
let transfer_family_index = physical_device
|
|
.queue_family_properties()
|
|
.iter()
|
|
.enumerate()
|
|
.filter(|(_, q)| {
|
|
q.queue_flags.intersects(QueueFlags::TRANSFER)
|
|
// Queue familes dedicated to transfers are not required to support partial
|
|
// transfers of images, reported by a mininum granularity of [0, 0, 0]. If you need
|
|
// to do partial transfers of images like we do in this example, you therefore have
|
|
// to make sure the queue family supports that.
|
|
&& q.min_image_transfer_granularity != [0; 3]
|
|
// Unlike queue familes for graphics and/or compute, queue familes dedicated to
|
|
// transfers don't have to support image transfers of arbitrary granularity.
|
|
// Therefore, if you are going to use one, you have to either make sure the
|
|
// granularity is granular enough for your needs, or you have to align your
|
|
// transfer offsets and extents to this granularity. Our minimum granularity is
|
|
// 4096 which should be more than coarse enough so we just check that it is.
|
|
&& q.min_image_transfer_granularity[0..2]
|
|
.iter()
|
|
.all(|&g| TRANSFER_GRANULARITY % g == 0)
|
|
})
|
|
.min_by_key(|(_, q)| q.queue_flags.count())
|
|
.unwrap()
|
|
.0 as u32;
|
|
|
|
let (device, mut queues) = {
|
|
let mut queue_create_infos = vec![QueueCreateInfo {
|
|
queue_family_index: graphics_family_index,
|
|
..Default::default()
|
|
}];
|
|
|
|
// It's possible that the physical device doesn't have any queue familes supporting
|
|
// transfers other than the graphics and/or compute queue family. In that case we must make
|
|
// sure we don't request the same queue family twice.
|
|
if transfer_family_index != graphics_family_index {
|
|
queue_create_infos.push(QueueCreateInfo {
|
|
queue_family_index: transfer_family_index,
|
|
..Default::default()
|
|
});
|
|
}
|
|
|
|
Device::new(
|
|
physical_device,
|
|
DeviceCreateInfo {
|
|
enabled_extensions: device_extensions,
|
|
queue_create_infos,
|
|
..Default::default()
|
|
},
|
|
)
|
|
.unwrap()
|
|
};
|
|
|
|
let graphics_queue = queues.next().unwrap();
|
|
|
|
// If we didn't get a dedicated transfer queue, fall back to the graphics queue for transfers.
|
|
let transfer_queue = queues.next().unwrap_or_else(|| graphics_queue.clone());
|
|
|
|
println!(
|
|
"Using queue family {graphics_family_index} for graphics and queue family \
|
|
{transfer_family_index} for transfers",
|
|
);
|
|
|
|
let (mut swapchain, images) = {
|
|
let surface_capabilities = device
|
|
.physical_device()
|
|
.surface_capabilities(&surface, Default::default())
|
|
.unwrap();
|
|
let image_format = device
|
|
.physical_device()
|
|
.surface_formats(&surface, Default::default())
|
|
.unwrap()[0]
|
|
.0;
|
|
|
|
Swapchain::new(
|
|
device.clone(),
|
|
surface,
|
|
SwapchainCreateInfo {
|
|
min_image_count: surface_capabilities.min_image_count.max(2),
|
|
image_format,
|
|
image_extent: window.inner_size().into(),
|
|
image_usage: ImageUsage::COLOR_ATTACHMENT,
|
|
composite_alpha: surface_capabilities
|
|
.supported_composite_alpha
|
|
.into_iter()
|
|
.next()
|
|
.unwrap(),
|
|
..Default::default()
|
|
},
|
|
)
|
|
.unwrap()
|
|
};
|
|
|
|
let memory_allocator = Arc::new(StandardMemoryAllocator::new_default(device.clone()));
|
|
|
|
#[derive(BufferContents, Vertex)]
|
|
#[repr(C)]
|
|
struct MyVertex {
|
|
#[format(R32G32_SFLOAT)]
|
|
position: [f32; 2],
|
|
}
|
|
|
|
let vertices = [
|
|
MyVertex {
|
|
position: [-0.5, -0.5],
|
|
},
|
|
MyVertex {
|
|
position: [-0.5, 0.5],
|
|
},
|
|
MyVertex {
|
|
position: [0.5, -0.5],
|
|
},
|
|
MyVertex {
|
|
position: [0.5, 0.5],
|
|
},
|
|
];
|
|
let vertex_buffer = Buffer::from_iter(
|
|
memory_allocator.clone(),
|
|
BufferCreateInfo {
|
|
usage: BufferUsage::VERTEX_BUFFER,
|
|
..Default::default()
|
|
},
|
|
AllocationCreateInfo {
|
|
memory_type_filter: MemoryTypeFilter::PREFER_DEVICE
|
|
| MemoryTypeFilter::HOST_SEQUENTIAL_WRITE,
|
|
..Default::default()
|
|
},
|
|
vertices,
|
|
)
|
|
.unwrap();
|
|
|
|
// Create a pool of uniform buffers, one per frame in flight. This way we always have an
|
|
// available buffer to write during each frame while reusing them as much as possible.
|
|
let uniform_buffers = (0..swapchain.image_count())
|
|
.map(|_| {
|
|
Buffer::new_sized(
|
|
memory_allocator.clone(),
|
|
BufferCreateInfo {
|
|
usage: BufferUsage::UNIFORM_BUFFER,
|
|
..Default::default()
|
|
},
|
|
AllocationCreateInfo {
|
|
memory_type_filter: MemoryTypeFilter::PREFER_DEVICE
|
|
| MemoryTypeFilter::HOST_SEQUENTIAL_WRITE,
|
|
..Default::default()
|
|
},
|
|
)
|
|
.unwrap()
|
|
})
|
|
.collect::<Vec<_>>();
|
|
|
|
// Create two textures, where at any point in time one is used exclusively for reading and one
|
|
// is used exclusively for writing, swapping the two after each update.
|
|
let textures = [(); 2].map(|_| {
|
|
Image::new(
|
|
memory_allocator.clone(),
|
|
ImageCreateInfo {
|
|
image_type: ImageType::Dim2d,
|
|
format: Format::R8G8B8A8_UNORM,
|
|
extent: [TRANSFER_GRANULARITY * 2, TRANSFER_GRANULARITY * 2, 1],
|
|
usage: ImageUsage::TRANSFER_DST | ImageUsage::SAMPLED,
|
|
..Default::default()
|
|
},
|
|
AllocationCreateInfo::default(),
|
|
)
|
|
.unwrap()
|
|
});
|
|
|
|
// The index of the currently most up-to-date texture. The worker thread swaps the index after
|
|
// every finished write, which is always done to the, at that point in time, unused texture.
|
|
let current_texture_index = Arc::new(AtomicBool::new(false));
|
|
|
|
// Current generation, used to notify the worker thread of when a texture is no longer read.
|
|
let current_generation = Arc::new(AtomicU64::new(0));
|
|
|
|
let command_buffer_allocator = Arc::new(StandardCommandBufferAllocator::new(
|
|
device.clone(),
|
|
Default::default(),
|
|
));
|
|
|
|
// Initialize the textures.
|
|
{
|
|
let mut builder = RecordingCommandBuffer::new(
|
|
command_buffer_allocator.clone(),
|
|
graphics_queue.queue_family_index(),
|
|
CommandBufferLevel::Primary,
|
|
CommandBufferBeginInfo {
|
|
usage: CommandBufferUsage::OneTimeSubmit,
|
|
..Default::default()
|
|
},
|
|
)
|
|
.unwrap();
|
|
for texture in &textures {
|
|
builder
|
|
.clear_color_image(ClearColorImageInfo::image(texture.clone()))
|
|
.unwrap();
|
|
}
|
|
let command_buffer = builder.end().unwrap();
|
|
|
|
// This waits for the queue to become idle, which is fine for startup initializations.
|
|
let _ = command_buffer.execute(graphics_queue.clone()).unwrap();
|
|
}
|
|
|
|
// Start the worker thread.
|
|
let (channel, receiver) = mpsc::channel();
|
|
run_worker(
|
|
receiver,
|
|
transfer_queue,
|
|
textures.clone(),
|
|
current_texture_index.clone(),
|
|
current_generation.clone(),
|
|
swapchain.image_count(),
|
|
memory_allocator,
|
|
command_buffer_allocator.clone(),
|
|
);
|
|
|
|
mod vs {
|
|
vulkano_shaders::shader! {
|
|
ty: "vertex",
|
|
src: r"
|
|
#version 450
|
|
|
|
layout(location = 0) in vec2 position;
|
|
layout(location = 0) out vec2 tex_coords;
|
|
|
|
layout(set = 0, binding = 0) uniform Data {
|
|
mat4 transform;
|
|
};
|
|
|
|
void main() {
|
|
gl_Position = vec4(transform * vec4(position, 0.0, 1.0));
|
|
tex_coords = position + vec2(0.5);
|
|
}
|
|
",
|
|
}
|
|
}
|
|
|
|
mod fs {
|
|
vulkano_shaders::shader! {
|
|
ty: "fragment",
|
|
src: r"
|
|
#version 450
|
|
|
|
layout(location = 0) in vec2 tex_coords;
|
|
layout(location = 0) out vec4 f_color;
|
|
|
|
layout(set = 1, binding = 0) uniform sampler s;
|
|
layout(set = 1, binding = 1) uniform texture2D tex;
|
|
|
|
void main() {
|
|
f_color = texture(sampler2D(tex, s), tex_coords);
|
|
}
|
|
",
|
|
}
|
|
}
|
|
|
|
let render_pass = vulkano::single_pass_renderpass!(
|
|
device.clone(),
|
|
attachments: {
|
|
color: {
|
|
format: swapchain.image_format(),
|
|
samples: 1,
|
|
load_op: Clear,
|
|
store_op: Store,
|
|
},
|
|
},
|
|
pass: {
|
|
color: [color],
|
|
depth_stencil: {},
|
|
},
|
|
)
|
|
.unwrap();
|
|
|
|
let pipeline = {
|
|
let vs = vs::load(device.clone())
|
|
.unwrap()
|
|
.entry_point("main")
|
|
.unwrap();
|
|
let fs = fs::load(device.clone())
|
|
.unwrap()
|
|
.entry_point("main")
|
|
.unwrap();
|
|
let vertex_input_state = MyVertex::per_vertex()
|
|
.definition(&vs.info().input_interface)
|
|
.unwrap();
|
|
let stages = [
|
|
PipelineShaderStageCreateInfo::new(vs),
|
|
PipelineShaderStageCreateInfo::new(fs),
|
|
];
|
|
let layout = PipelineLayout::new(
|
|
device.clone(),
|
|
PipelineDescriptorSetLayoutCreateInfo::from_stages(&stages)
|
|
.into_pipeline_layout_create_info(device.clone())
|
|
.unwrap(),
|
|
)
|
|
.unwrap();
|
|
let subpass = Subpass::from(render_pass.clone(), 0).unwrap();
|
|
|
|
GraphicsPipeline::new(
|
|
device.clone(),
|
|
None,
|
|
GraphicsPipelineCreateInfo {
|
|
stages: stages.into_iter().collect(),
|
|
vertex_input_state: Some(vertex_input_state),
|
|
input_assembly_state: Some(InputAssemblyState {
|
|
topology: PrimitiveTopology::TriangleStrip,
|
|
..Default::default()
|
|
}),
|
|
viewport_state: Some(ViewportState::default()),
|
|
rasterization_state: Some(RasterizationState::default()),
|
|
multisample_state: Some(MultisampleState::default()),
|
|
color_blend_state: Some(ColorBlendState::with_attachment_states(
|
|
subpass.num_color_attachments(),
|
|
ColorBlendAttachmentState::default(),
|
|
)),
|
|
dynamic_state: [DynamicState::Viewport].into_iter().collect(),
|
|
subpass: Some(subpass.into()),
|
|
..GraphicsPipelineCreateInfo::layout(layout)
|
|
},
|
|
)
|
|
.unwrap()
|
|
};
|
|
|
|
let mut viewport = Viewport {
|
|
offset: [0.0, 0.0],
|
|
extent: [0.0, 0.0],
|
|
depth_range: 0.0..=1.0,
|
|
};
|
|
let mut framebuffers = window_size_dependent_setup(&images, render_pass.clone(), &mut viewport);
|
|
|
|
let descriptor_set_allocator = Arc::new(StandardDescriptorSetAllocator::new(
|
|
device.clone(),
|
|
Default::default(),
|
|
));
|
|
|
|
// A byproduct of always using the same set of uniform buffers is that we can also create one
|
|
// descriptor set for each, reusing them in the same way as the buffers.
|
|
let uniform_buffer_sets = uniform_buffers
|
|
.iter()
|
|
.map(|buffer| {
|
|
DescriptorSet::new(
|
|
descriptor_set_allocator.clone(),
|
|
pipeline.layout().set_layouts()[0].clone(),
|
|
[WriteDescriptorSet::buffer(0, buffer.clone())],
|
|
[],
|
|
)
|
|
.unwrap()
|
|
})
|
|
.collect::<Vec<_>>();
|
|
|
|
// Create the descriptor sets for sampling the textures.
|
|
let sampler = Sampler::new(device.clone(), SamplerCreateInfo::simple_repeat_linear()).unwrap();
|
|
let sampler_sets = textures.map(|texture| {
|
|
DescriptorSet::new(
|
|
descriptor_set_allocator.clone(),
|
|
pipeline.layout().set_layouts()[1].clone(),
|
|
[
|
|
WriteDescriptorSet::sampler(0, sampler.clone()),
|
|
WriteDescriptorSet::image_view(1, ImageView::new_default(texture).unwrap()),
|
|
],
|
|
[],
|
|
)
|
|
.unwrap()
|
|
});
|
|
|
|
let mut recreate_swapchain = false;
|
|
let mut previous_frame_end = Some(sync::now(device.clone()).boxed());
|
|
|
|
println!("\nPress space to update part of the texture");
|
|
|
|
event_loop.run(move |event, elwt| {
|
|
elwt.set_control_flow(ControlFlow::Poll);
|
|
|
|
match event {
|
|
Event::WindowEvent {
|
|
event: WindowEvent::CloseRequested,
|
|
..
|
|
} => {
|
|
elwt.exit();
|
|
}
|
|
Event::WindowEvent {
|
|
event: WindowEvent::Resized(_),
|
|
..
|
|
} => {
|
|
recreate_swapchain = true;
|
|
}
|
|
Event::WindowEvent {
|
|
event:
|
|
WindowEvent::KeyboardInput {
|
|
event:
|
|
KeyEvent {
|
|
logical_key: Key::Named(NamedKey::Space),
|
|
state: ElementState::Released,
|
|
..
|
|
},
|
|
..
|
|
},
|
|
..
|
|
} => {
|
|
channel.send(()).unwrap();
|
|
}
|
|
Event::WindowEvent {
|
|
event: WindowEvent::RedrawRequested,
|
|
..
|
|
} => {
|
|
let image_extent: [u32; 2] = window.inner_size().into();
|
|
|
|
if image_extent.contains(&0) {
|
|
return;
|
|
}
|
|
|
|
if recreate_swapchain {
|
|
let (new_swapchain, new_images) = swapchain
|
|
.recreate(SwapchainCreateInfo {
|
|
image_extent,
|
|
..swapchain.create_info()
|
|
})
|
|
.expect("failed to recreate swapchain");
|
|
|
|
swapchain = new_swapchain;
|
|
framebuffers = window_size_dependent_setup(
|
|
&new_images,
|
|
render_pass.clone(),
|
|
&mut viewport,
|
|
);
|
|
recreate_swapchain = false;
|
|
}
|
|
|
|
let (image_index, suboptimal, acquire_future) =
|
|
match acquire_next_image(swapchain.clone(), None).map_err(Validated::unwrap) {
|
|
Ok(r) => r,
|
|
Err(VulkanError::OutOfDate) => {
|
|
recreate_swapchain = true;
|
|
return;
|
|
}
|
|
Err(e) => panic!("failed to acquire next image: {e}"),
|
|
};
|
|
|
|
if suboptimal {
|
|
recreate_swapchain = true;
|
|
}
|
|
|
|
let mut builder = RecordingCommandBuffer::new(
|
|
command_buffer_allocator.clone(),
|
|
graphics_queue.queue_family_index(),
|
|
CommandBufferLevel::Primary,
|
|
CommandBufferBeginInfo {
|
|
usage: CommandBufferUsage::OneTimeSubmit,
|
|
..Default::default()
|
|
},
|
|
)
|
|
.unwrap();
|
|
|
|
builder
|
|
.begin_render_pass(
|
|
RenderPassBeginInfo {
|
|
clear_values: vec![Some([0.0, 0.0, 0.0, 1.0].into())],
|
|
..RenderPassBeginInfo::framebuffer(
|
|
framebuffers[image_index as usize].clone(),
|
|
)
|
|
},
|
|
Default::default(),
|
|
)
|
|
.unwrap()
|
|
.set_viewport(0, [viewport.clone()].into_iter().collect())
|
|
.unwrap()
|
|
.bind_pipeline_graphics(pipeline.clone())
|
|
.unwrap()
|
|
.bind_descriptor_sets(
|
|
PipelineBindPoint::Graphics,
|
|
pipeline.layout().clone(),
|
|
0,
|
|
(
|
|
// Bind the uniform buffer designated for this frame.
|
|
uniform_buffer_sets[image_index as usize].clone(),
|
|
// Bind the currenly most up-to-date texture.
|
|
sampler_sets[current_texture_index.load(Ordering::Acquire) as usize]
|
|
.clone(),
|
|
),
|
|
)
|
|
.unwrap()
|
|
.bind_vertex_buffers(0, vertex_buffer.clone())
|
|
.unwrap();
|
|
|
|
unsafe {
|
|
builder.draw(vertex_buffer.len() as u32, 1, 0, 0).unwrap();
|
|
}
|
|
|
|
builder.end_render_pass(Default::default()).unwrap();
|
|
|
|
let command_buffer = builder.end().unwrap();
|
|
acquire_future.wait(None).unwrap();
|
|
previous_frame_end.as_mut().unwrap().cleanup_finished();
|
|
|
|
// Write to the uniform buffer designated for this frame. This must happen after
|
|
// waiting for the acquire future and cleaning up, otherwise the buffer is still
|
|
// going to be marked as in use by the device.
|
|
*uniform_buffers[image_index as usize].write().unwrap() = vs::Data {
|
|
transform: {
|
|
const DURATION: f64 = 5.0;
|
|
|
|
let elapsed = SystemTime::now()
|
|
.duration_since(UNIX_EPOCH)
|
|
.unwrap()
|
|
.as_secs_f64();
|
|
let remainder = elapsed.rem_euclid(DURATION);
|
|
let delta = (remainder / DURATION) as f32;
|
|
let angle = delta * std::f32::consts::PI * 2.0;
|
|
|
|
Matrix4::from_angle_z(Rad(angle)).into()
|
|
},
|
|
};
|
|
|
|
// Increment the generation, signalling that the previous frame has finished. This
|
|
// must be done after waiting on the acquire future, otherwise the oldest frame
|
|
// would still be in flight.
|
|
//
|
|
// NOTE: We are relying on the fact that this thread is the only one doing stores.
|
|
current_generation.fetch_add(1, Ordering::Release);
|
|
|
|
let future = previous_frame_end
|
|
.take()
|
|
.unwrap()
|
|
.join(acquire_future)
|
|
.then_execute(graphics_queue.clone(), command_buffer)
|
|
.unwrap()
|
|
.then_swapchain_present(
|
|
graphics_queue.clone(),
|
|
SwapchainPresentInfo::swapchain_image_index(swapchain.clone(), image_index),
|
|
)
|
|
.then_signal_fence_and_flush();
|
|
|
|
match future.map_err(Validated::unwrap) {
|
|
Ok(future) => {
|
|
previous_frame_end = Some(future.boxed());
|
|
}
|
|
Err(VulkanError::OutOfDate) => {
|
|
recreate_swapchain = true;
|
|
previous_frame_end = Some(sync::now(device.clone()).boxed());
|
|
}
|
|
Err(e) => {
|
|
println!("failed to flush future: {e}");
|
|
// previous_frame_end = Some(sync::now(device.clone()).boxed());
|
|
}
|
|
}
|
|
}
|
|
Event::AboutToWait => window.request_redraw(),
|
|
_ => (),
|
|
}
|
|
})
|
|
}
|
|
|
|
#[allow(clippy::too_many_arguments)]
|
|
fn run_worker(
|
|
channel: mpsc::Receiver<()>,
|
|
transfer_queue: Arc<Queue>,
|
|
textures: [Arc<Image>; 2],
|
|
current_texture_index: Arc<AtomicBool>,
|
|
current_generation: Arc<AtomicU64>,
|
|
swapchain_image_count: u32,
|
|
memory_allocator: Arc<StandardMemoryAllocator>,
|
|
command_buffer_allocator: Arc<StandardCommandBufferAllocator>,
|
|
) {
|
|
thread::spawn(move || {
|
|
const CORNER_OFFSETS: [[u32; 3]; 4] = [
|
|
[0, 0, 0],
|
|
[TRANSFER_GRANULARITY, 0, 0],
|
|
[TRANSFER_GRANULARITY, TRANSFER_GRANULARITY, 0],
|
|
[0, TRANSFER_GRANULARITY, 0],
|
|
];
|
|
|
|
// We are going to be updating one of 4 corners of the texture at any point in time. For
|
|
// that, we will use a staging buffer and initiate a copy. However, since our texture is
|
|
// eventually consistent and there are 2 replicas, that means that every time we update one
|
|
// of the replicas the other replica is going to be behind by one update. Therefore we
|
|
// actually need 2 staging buffers as well: one for the update that happened to the
|
|
// currently up-to-date texture (at `current_index`) and one for the update that is about
|
|
// to happen to the currently out-of-date texture (at `!current_index`), so that we can
|
|
// apply both the current and the upcoming update to the out-of-date texture. Then the
|
|
// out-of-date texture is the current up-to-date texture and vice-versa, cycle repeating.
|
|
let staging_buffers = [(); 2].map(|_| {
|
|
Buffer::from_iter(
|
|
memory_allocator.clone(),
|
|
BufferCreateInfo {
|
|
usage: BufferUsage::TRANSFER_SRC,
|
|
..Default::default()
|
|
},
|
|
AllocationCreateInfo {
|
|
memory_type_filter: MemoryTypeFilter::PREFER_HOST
|
|
| MemoryTypeFilter::HOST_SEQUENTIAL_WRITE,
|
|
..Default::default()
|
|
},
|
|
(0..TRANSFER_GRANULARITY * TRANSFER_GRANULARITY).map(|_| [0u8; 4]),
|
|
)
|
|
.unwrap()
|
|
});
|
|
|
|
let mut current_corner = 0;
|
|
let mut rng = rand::thread_rng();
|
|
let mut last_generation = 0;
|
|
|
|
// The worker thread is awakened by sending a signal through the channel. In a real program
|
|
// you would likely send some actual data over the channel, instructing the worker what to
|
|
// do, but our work is hard-coded.
|
|
while let Ok(()) = channel.recv() {
|
|
let current_index = current_texture_index.load(Ordering::Acquire);
|
|
|
|
// We simulate some work for the worker to indulge in. In a real program this would
|
|
// likely be some kind of I/O, for example reading from disk (think loading the next
|
|
// level in a level-based game, loading the next chunk of terrain in an open-world
|
|
// game, etc.) or downloading images or other data from the internet.
|
|
//
|
|
// NOTE: The size of these textures is exceedingly large on purpose, so that you can
|
|
// feel that the update is in fact asynchronous due to the latency of the updates while
|
|
// the rendering continues without any.
|
|
let color = [rng.gen(), rng.gen(), rng.gen(), u8::MAX];
|
|
for texel in &mut *staging_buffers[!current_index as usize].write().unwrap() {
|
|
*texel = color;
|
|
}
|
|
|
|
// Write to the texture that's currently not in use for rendering.
|
|
let texture = textures[!current_index as usize].clone();
|
|
|
|
let mut builder = RecordingCommandBuffer::new(
|
|
command_buffer_allocator.clone(),
|
|
transfer_queue.queue_family_index(),
|
|
CommandBufferLevel::Primary,
|
|
CommandBufferBeginInfo {
|
|
usage: CommandBufferUsage::OneTimeSubmit,
|
|
..Default::default()
|
|
},
|
|
)
|
|
.unwrap();
|
|
builder
|
|
.copy_buffer_to_image(CopyBufferToImageInfo {
|
|
regions: [BufferImageCopy {
|
|
image_subresource: texture.subresource_layers(),
|
|
image_offset: CORNER_OFFSETS[current_corner % 4],
|
|
image_extent: [TRANSFER_GRANULARITY, TRANSFER_GRANULARITY, 1],
|
|
..Default::default()
|
|
}]
|
|
.into(),
|
|
..CopyBufferToImageInfo::buffer_image(
|
|
staging_buffers[current_index as usize].clone(),
|
|
texture.clone(),
|
|
)
|
|
})
|
|
.unwrap()
|
|
.copy_buffer_to_image(CopyBufferToImageInfo {
|
|
regions: [BufferImageCopy {
|
|
image_subresource: texture.subresource_layers(),
|
|
image_offset: CORNER_OFFSETS[(current_corner + 1) % 4],
|
|
image_extent: [TRANSFER_GRANULARITY, TRANSFER_GRANULARITY, 1],
|
|
..Default::default()
|
|
}]
|
|
.into(),
|
|
..CopyBufferToImageInfo::buffer_image(
|
|
staging_buffers[!current_index as usize].clone(),
|
|
texture,
|
|
)
|
|
})
|
|
.unwrap();
|
|
let command_buffer = builder.end().unwrap();
|
|
|
|
// We swap the texture index to use after a write, but there is no guarantee that other
|
|
// tasks have actually moved on to using the new texture. What could happen then, if
|
|
// the writes being done are quicker than rendering a frame (or any other task reading
|
|
// the same resource), is the following:
|
|
//
|
|
// 1. Task A starts reading texture 0
|
|
// 2. Task B writes texture 1, swapping the index
|
|
// 3. Task B writes texture 0, swapping the index
|
|
// 4. Task A stops reading texture 0
|
|
//
|
|
// This is known as the A/B/A problem. In this case it results in a race condition,
|
|
// since task A (rendering, in our case) is still reading texture 0 while task B (our
|
|
// worker) has already started writing the very same texture.
|
|
//
|
|
// The most common way to solve this issue is using *generations*, also known as
|
|
// *epochs*. A generation is simply a monotonically increasing integer. What exactly
|
|
// one generation represents depends on the application. In our case, one generation
|
|
// passed represents one frame that finished rendering. Knowing this, we can keep track
|
|
// of the generation at the time of swapping the texture index, and ensure that any
|
|
// further write only happens after a generation was reached which makes it impossible
|
|
// for any readers to be stuck on the old index. Here we are simply spinning.
|
|
//
|
|
// NOTE: You could also use the thread for other things in the meantime. Since frames
|
|
// are typically very short though, it would make no sense to do that in this case.
|
|
while current_generation.load(Ordering::Acquire) - last_generation
|
|
< swapchain_image_count as u64
|
|
{
|
|
hint::spin_loop();
|
|
}
|
|
|
|
// Execute the transfer, blocking the thread until it finishes.
|
|
//
|
|
// NOTE: You could also use the thread for other things in the meantime.
|
|
command_buffer
|
|
.execute(transfer_queue.clone())
|
|
.unwrap()
|
|
.then_signal_fence_and_flush()
|
|
.unwrap()
|
|
.wait(None)
|
|
.unwrap();
|
|
|
|
// Remember the latest generation.
|
|
last_generation = current_generation.load(Ordering::Acquire);
|
|
|
|
// Swap the texture used for rendering to the newly updated one.
|
|
//
|
|
// NOTE: We are relying on the fact that this thread is the only one doing stores.
|
|
current_texture_index.store(!current_index, Ordering::Release);
|
|
|
|
current_corner += 1;
|
|
}
|
|
});
|
|
}
|
|
|
|
/// 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>,
|
|
viewport: &mut Viewport,
|
|
) -> Vec<Arc<Framebuffer>> {
|
|
let extent = images[0].extent();
|
|
viewport.extent = [extent[0] as f32, extent[1] as f32];
|
|
|
|
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<_>>()
|
|
}
|