mirror of
https://github.com/vulkano-rs/vulkano.git
synced 2024-11-22 06:45:23 +00:00
699 lines
25 KiB
Rust
699 lines
25 KiB
Rust
// A minimal particle-sandbox to demonstrate a reasonable use-case for a device-local buffer. We
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// gain significant runtime performance by writing the initial vertex values to the GPU using a
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// staging buffer and then copying the data to a device-local buffer to be accessed solely by the
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// GPU through the compute shader and as a vertex array.
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use std::{error::Error, sync::Arc, time::SystemTime};
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use vulkano::{
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buffer::{Buffer, BufferContents, BufferCreateInfo, BufferUsage, Subbuffer},
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command_buffer::{
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allocator::StandardCommandBufferAllocator, AutoCommandBufferBuilder, CommandBufferUsage,
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CopyBufferInfo, RenderPassBeginInfo,
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},
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descriptor_set::{
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allocator::StandardDescriptorSetAllocator, DescriptorSet, WriteDescriptorSet,
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},
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device::{
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physical::PhysicalDeviceType, Device, DeviceCreateInfo, DeviceExtensions, Queue,
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QueueCreateInfo, QueueFlags,
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},
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image::{view::ImageView, ImageUsage},
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instance::{Instance, InstanceCreateFlags, InstanceCreateInfo},
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memory::allocator::{AllocationCreateInfo, MemoryTypeFilter, StandardMemoryAllocator},
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pipeline::{
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compute::ComputePipelineCreateInfo,
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graphics::{
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color_blend::{ColorBlendAttachmentState, ColorBlendState},
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input_assembly::{InputAssemblyState, PrimitiveTopology},
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multisample::MultisampleState,
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rasterization::RasterizationState,
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vertex_input::{Vertex, VertexDefinition},
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viewport::{Viewport, ViewportState},
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GraphicsPipelineCreateInfo,
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},
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layout::PipelineDescriptorSetLayoutCreateInfo,
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ComputePipeline, GraphicsPipeline, Pipeline, PipelineBindPoint, PipelineLayout,
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PipelineShaderStageCreateInfo,
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},
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render_pass::{Framebuffer, FramebufferCreateInfo, Subpass},
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swapchain::{
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acquire_next_image, PresentMode, Surface, Swapchain, SwapchainCreateInfo,
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SwapchainPresentInfo,
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},
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sync::{self, GpuFuture},
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DeviceSize, Validated, VulkanLibrary,
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};
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use winit::{
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application::ApplicationHandler,
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dpi::PhysicalSize,
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event::WindowEvent,
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event_loop::{ActiveEventLoop, EventLoop},
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window::{Window, WindowId},
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};
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const WINDOW_WIDTH: u32 = 800;
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const WINDOW_HEIGHT: u32 = 600;
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const PARTICLE_COUNT: usize = 100_000;
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fn main() -> Result<(), impl Error> {
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// The usual Vulkan initialization. Largely the same as the triangle example until further
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// commentation is provided.
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let event_loop = EventLoop::new().unwrap();
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let mut app = App::new(&event_loop);
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event_loop.run_app(&mut app)
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}
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struct App {
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instance: Arc<Instance>,
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device: Arc<Device>,
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queue: Arc<Queue>,
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command_buffer_allocator: Arc<StandardCommandBufferAllocator>,
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vertex_buffer: Subbuffer<[MyVertex]>,
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compute_pipeline: Arc<ComputePipeline>,
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descriptor_set: Arc<DescriptorSet>,
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rcx: Option<RenderContext>,
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}
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struct RenderContext {
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window: Arc<Window>,
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swapchain: Arc<Swapchain>,
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framebuffers: Vec<Arc<Framebuffer>>,
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pipeline: Arc<GraphicsPipeline>,
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previous_frame_end: Option<Box<dyn GpuFuture>>,
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start_time: SystemTime,
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last_frame_time: SystemTime,
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}
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impl App {
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fn new(event_loop: &EventLoop<()>) -> Self {
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let library = VulkanLibrary::new().unwrap();
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let required_extensions = Surface::required_extensions(event_loop).unwrap();
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let instance = Instance::new(
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library,
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InstanceCreateInfo {
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enabled_extensions: required_extensions,
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flags: InstanceCreateFlags::ENUMERATE_PORTABILITY,
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..Default::default()
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},
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)
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.unwrap();
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let device_extensions = DeviceExtensions {
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khr_swapchain: true,
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..DeviceExtensions::empty()
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};
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let (physical_device, queue_family_index) = instance
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.enumerate_physical_devices()
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.unwrap()
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.filter(|p| p.supported_extensions().contains(&device_extensions))
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.filter_map(|p| {
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p.queue_family_properties()
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.iter()
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.enumerate()
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.position(|(i, q)| {
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q.queue_flags.intersects(QueueFlags::GRAPHICS)
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&& p.presentation_support(i as u32, event_loop).unwrap()
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})
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.map(|i| (p, i as u32))
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})
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.min_by_key(|(p, _)| match p.properties().device_type {
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PhysicalDeviceType::DiscreteGpu => 0,
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PhysicalDeviceType::IntegratedGpu => 1,
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PhysicalDeviceType::VirtualGpu => 2,
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PhysicalDeviceType::Cpu => 3,
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PhysicalDeviceType::Other => 4,
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_ => 5,
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})
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.unwrap();
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println!(
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"Using device: {} (type: {:?})",
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physical_device.properties().device_name,
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physical_device.properties().device_type,
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);
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let (device, mut queues) = Device::new(
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physical_device,
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DeviceCreateInfo {
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enabled_extensions: device_extensions,
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queue_create_infos: vec![QueueCreateInfo {
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queue_family_index,
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..Default::default()
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}],
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..Default::default()
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},
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)
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.unwrap();
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let queue = queues.next().unwrap();
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let memory_allocator = Arc::new(StandardMemoryAllocator::new_default(device.clone()));
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let descriptor_set_allocator = Arc::new(StandardDescriptorSetAllocator::new(
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device.clone(),
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Default::default(),
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));
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let command_buffer_allocator = Arc::new(StandardCommandBufferAllocator::new(
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device.clone(),
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Default::default(),
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));
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// Apply scoped logic to create `DeviceLocalBuffer` initialized with vertex data.
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let vertex_buffer = {
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// Initialize vertex data as an iterator.
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let vertices = (0..PARTICLE_COUNT).map(|i| {
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let f = i as f32 / (PARTICLE_COUNT / 10) as f32;
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MyVertex {
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pos: [2. * f.fract() - 1., 0.2 * f.floor() - 1.],
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vel: [0.; 2],
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}
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});
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// Create a CPU-accessible buffer initialized with the vertex data.
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let temporary_accessible_buffer = Buffer::from_iter(
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memory_allocator.clone(),
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BufferCreateInfo {
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// Specify this buffer will be used as a transfer source.
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usage: BufferUsage::TRANSFER_SRC,
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..Default::default()
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},
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AllocationCreateInfo {
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// Specify this buffer will be used for uploading to the GPU.
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memory_type_filter: MemoryTypeFilter::PREFER_HOST
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| MemoryTypeFilter::HOST_SEQUENTIAL_WRITE,
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..Default::default()
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},
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vertices,
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)
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.unwrap();
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// Create a buffer in device-local memory with enough space for `PARTICLE_COUNT`
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// number of `Vertex`.
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let device_local_buffer = Buffer::new_slice::<MyVertex>(
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memory_allocator,
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BufferCreateInfo {
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// Specify use as a storage buffer, vertex buffer, and transfer destination.
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usage: BufferUsage::STORAGE_BUFFER
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| BufferUsage::TRANSFER_DST
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| BufferUsage::VERTEX_BUFFER,
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..Default::default()
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},
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AllocationCreateInfo {
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// Specify this buffer will only be used by the device.
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memory_type_filter: MemoryTypeFilter::PREFER_DEVICE,
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..Default::default()
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},
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PARTICLE_COUNT as DeviceSize,
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)
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.unwrap();
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// Create one-time command to copy between the buffers.
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let mut cbb = AutoCommandBufferBuilder::primary(
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command_buffer_allocator.clone(),
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queue.queue_family_index(),
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CommandBufferUsage::OneTimeSubmit,
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)
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.unwrap();
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cbb.copy_buffer(CopyBufferInfo::buffers(
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temporary_accessible_buffer,
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device_local_buffer.clone(),
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))
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.unwrap();
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let cb = cbb.build().unwrap();
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// Execute copy and wait for copy to complete before proceeding.
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cb.execute(queue.clone())
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.unwrap()
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.then_signal_fence_and_flush()
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.unwrap()
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.wait(None /* timeout */)
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.unwrap();
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device_local_buffer
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};
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// Create a compute-pipeline for applying the compute shader to vertices.
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let compute_pipeline = {
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let cs = cs::load(device.clone())
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.unwrap()
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.entry_point("main")
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.unwrap();
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let stage = PipelineShaderStageCreateInfo::new(cs);
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let layout = PipelineLayout::new(
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device.clone(),
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PipelineDescriptorSetLayoutCreateInfo::from_stages([&stage])
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.into_pipeline_layout_create_info(device.clone())
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.unwrap(),
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)
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.unwrap();
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ComputePipeline::new(
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device.clone(),
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None,
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ComputePipelineCreateInfo::stage_layout(stage, layout),
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)
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.unwrap()
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};
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// Create a new descriptor set for binding vertices as a storage buffer.
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let descriptor_set = DescriptorSet::new(
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descriptor_set_allocator.clone(),
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// 0 is the index of the descriptor set.
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compute_pipeline.layout().set_layouts()[0].clone(),
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[
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// 0 is the binding of the data in this set. We bind the `Buffer` of vertices here.
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WriteDescriptorSet::buffer(0, vertex_buffer.clone()),
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],
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[],
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)
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.unwrap();
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App {
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instance,
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device,
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queue,
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command_buffer_allocator,
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vertex_buffer,
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compute_pipeline,
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descriptor_set,
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rcx: None,
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}
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}
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}
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impl ApplicationHandler for App {
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fn resumed(&mut self, event_loop: &ActiveEventLoop) {
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let window = Arc::new(
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event_loop
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.create_window(
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Window::default_attributes()
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// For simplicity, we are going to assert that the window size is static.
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.with_resizable(false)
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.with_title("simple particles")
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.with_inner_size(PhysicalSize::new(WINDOW_WIDTH, WINDOW_HEIGHT)),
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)
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.unwrap(),
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);
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let surface = Surface::from_window(self.instance.clone(), window.clone()).unwrap();
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let (swapchain, images) = {
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let surface_capabilities = self
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.device
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.physical_device()
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.surface_capabilities(&surface, Default::default())
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.unwrap();
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let (image_format, _) = self
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.device
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.physical_device()
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.surface_formats(&surface, Default::default())
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.unwrap()[0];
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Swapchain::new(
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self.device.clone(),
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surface,
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SwapchainCreateInfo {
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min_image_count: surface_capabilities.min_image_count.max(2),
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image_format,
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image_extent: [WINDOW_WIDTH, WINDOW_HEIGHT],
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image_usage: ImageUsage::COLOR_ATTACHMENT,
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composite_alpha: surface_capabilities
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.supported_composite_alpha
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.into_iter()
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.next()
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.unwrap(),
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present_mode: PresentMode::Fifo,
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..Default::default()
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},
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)
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.unwrap()
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};
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let render_pass = vulkano::single_pass_renderpass!(
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self.device.clone(),
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attachments: {
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color: {
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format: swapchain.image_format(),
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samples: 1,
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load_op: Clear,
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store_op: Store,
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},
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},
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pass: {
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color: [color],
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depth_stencil: {},
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},
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)
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.unwrap();
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let framebuffers = images
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.into_iter()
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.map(|img| {
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let view = ImageView::new_default(img).unwrap();
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Framebuffer::new(
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render_pass.clone(),
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FramebufferCreateInfo {
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attachments: vec![view],
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..Default::default()
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},
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)
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.unwrap()
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})
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.collect();
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// The vertex shader determines color and is run once per particle. The vertices will be
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// updated by the compute shader each frame.
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mod vs {
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vulkano_shaders::shader! {
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ty: "vertex",
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src: r"
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#version 450
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layout(location = 0) in vec2 pos;
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layout(location = 1) in vec2 vel;
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layout(location = 0) out vec4 outColor;
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// Keep this value in sync with the `maxSpeed` const in the compute shader.
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const float maxSpeed = 10.0;
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void main() {
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gl_Position = vec4(pos, 0.0, 1.0);
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gl_PointSize = 1.0;
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// Mix colors based on position and velocity.
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outColor = mix(
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0.2 * vec4(pos, abs(vel.x) + abs(vel.y), 1.0),
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vec4(1.0, 0.5, 0.8, 1.0),
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sqrt(length(vel) / maxSpeed)
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);
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}
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",
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}
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}
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// The fragment shader will only need to apply the color forwarded by the vertex shader,
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// because the color of a particle should be identical over all pixels.
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mod fs {
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vulkano_shaders::shader! {
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ty: "fragment",
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src: r"
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#version 450
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layout(location = 0) in vec4 outColor;
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layout(location = 0) out vec4 fragColor;
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void main() {
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fragColor = outColor;
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}
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",
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}
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}
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// Create a basic graphics pipeline for rendering particles.
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let pipeline = {
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let vs = vs::load(self.device.clone())
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.unwrap()
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.entry_point("main")
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.unwrap();
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let fs = fs::load(self.device.clone())
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.unwrap()
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.entry_point("main")
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.unwrap();
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let vertex_input_state = MyVertex::per_vertex().definition(&vs).unwrap();
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let stages = [
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PipelineShaderStageCreateInfo::new(vs),
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PipelineShaderStageCreateInfo::new(fs),
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];
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let layout = PipelineLayout::new(
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self.device.clone(),
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PipelineDescriptorSetLayoutCreateInfo::from_stages(&stages)
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.into_pipeline_layout_create_info(self.device.clone())
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.unwrap(),
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)
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.unwrap();
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let subpass = Subpass::from(render_pass, 0).unwrap();
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GraphicsPipeline::new(
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self.device.clone(),
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None,
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GraphicsPipelineCreateInfo {
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stages: stages.into_iter().collect(),
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vertex_input_state: Some(vertex_input_state),
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// Vertices will be rendered as a list of points.
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input_assembly_state: Some(InputAssemblyState {
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topology: PrimitiveTopology::PointList,
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..Default::default()
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}),
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viewport_state: Some(ViewportState {
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viewports: [Viewport {
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offset: [0.0, 0.0],
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extent: [WINDOW_WIDTH as f32, WINDOW_HEIGHT as f32],
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depth_range: 0.0..=1.0,
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}]
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.into_iter()
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.collect(),
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..Default::default()
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}),
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rasterization_state: Some(RasterizationState::default()),
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multisample_state: Some(MultisampleState::default()),
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color_blend_state: Some(ColorBlendState::with_attachment_states(
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subpass.num_color_attachments(),
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ColorBlendAttachmentState::default(),
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)),
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subpass: Some(subpass.into()),
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..GraphicsPipelineCreateInfo::layout(layout)
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},
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)
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.unwrap()
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};
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let previous_frame_end = Some(sync::now(self.device.clone()).boxed());
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let start_time = SystemTime::now();
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self.rcx = Some(RenderContext {
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window,
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swapchain,
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framebuffers,
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pipeline,
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previous_frame_end,
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start_time,
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last_frame_time: start_time,
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});
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}
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fn window_event(
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&mut self,
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event_loop: &ActiveEventLoop,
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_window_id: WindowId,
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event: WindowEvent,
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) {
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let rcx = self.rcx.as_mut().unwrap();
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match event {
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WindowEvent::CloseRequested => {
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event_loop.exit();
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}
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WindowEvent::RedrawRequested => {
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let window_size = rcx.window.inner_size();
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if window_size.width == 0 || window_size.height == 0 {
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return;
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}
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rcx.previous_frame_end.as_mut().unwrap().cleanup_finished();
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|
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// Update per-frame variables.
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let now = SystemTime::now();
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let time = now.duration_since(rcx.start_time).unwrap().as_secs_f32();
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let delta_time = now
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.duration_since(rcx.last_frame_time)
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.unwrap()
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.as_secs_f32();
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rcx.last_frame_time = now;
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// Create push constants to be passed to compute shader.
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let push_constants = cs::PushConstants {
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attractor: [0.75 * (3. * time).cos(), 0.6 * (0.75 * time).sin()],
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attractor_strength: 1.2 * (2. * time).cos(),
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delta_time,
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};
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|
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// Acquire information on the next swapchain target.
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let (image_index, suboptimal, acquire_future) = match acquire_next_image(
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rcx.swapchain.clone(),
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None, // timeout
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) {
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Ok(tuple) => tuple,
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Err(e) => panic!("failed to acquire next image: {e}"),
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};
|
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|
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// Since we disallow resizing, assert that the swapchain and surface are
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// optimally configured.
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assert!(
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!suboptimal,
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|
"not handling sub-optimal swapchains in this sample code",
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);
|
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|
|
let mut builder = AutoCommandBufferBuilder::primary(
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|
self.command_buffer_allocator.clone(),
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|
self.queue.queue_family_index(),
|
|
CommandBufferUsage::OneTimeSubmit,
|
|
)
|
|
.unwrap();
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|
|
builder
|
|
// Push constants for compute shader.
|
|
.push_constants(self.compute_pipeline.layout().clone(), 0, push_constants)
|
|
.unwrap()
|
|
// Perform compute operation to update particle positions.
|
|
.bind_pipeline_compute(self.compute_pipeline.clone())
|
|
.unwrap()
|
|
.bind_descriptor_sets(
|
|
PipelineBindPoint::Compute,
|
|
self.compute_pipeline.layout().clone(),
|
|
0, // Bind this descriptor set to index 0.
|
|
self.descriptor_set.clone(),
|
|
)
|
|
.unwrap();
|
|
unsafe { builder.dispatch([PARTICLE_COUNT as u32 / 128, 1, 1]) }.unwrap();
|
|
|
|
// Use render-pass to draw particles to swapchain.
|
|
builder
|
|
.begin_render_pass(
|
|
RenderPassBeginInfo {
|
|
clear_values: vec![Some([0., 0., 0., 1.].into())],
|
|
..RenderPassBeginInfo::framebuffer(
|
|
rcx.framebuffers[image_index as usize].clone(),
|
|
)
|
|
},
|
|
Default::default(),
|
|
)
|
|
.unwrap()
|
|
.bind_pipeline_graphics(rcx.pipeline.clone())
|
|
.unwrap()
|
|
.bind_vertex_buffers(0, self.vertex_buffer.clone())
|
|
.unwrap();
|
|
unsafe { builder.draw(PARTICLE_COUNT as u32, 1, 0, 0) }.unwrap();
|
|
|
|
builder.end_render_pass(Default::default()).unwrap();
|
|
|
|
let command_buffer = builder.build().unwrap();
|
|
let future = rcx
|
|
.previous_frame_end
|
|
.take()
|
|
.unwrap()
|
|
.join(acquire_future)
|
|
.then_execute(self.queue.clone(), command_buffer)
|
|
.unwrap()
|
|
.then_swapchain_present(
|
|
self.queue.clone(),
|
|
SwapchainPresentInfo::swapchain_image_index(
|
|
rcx.swapchain.clone(),
|
|
image_index,
|
|
),
|
|
)
|
|
.then_signal_fence_and_flush();
|
|
|
|
rcx.previous_frame_end = match future.map_err(Validated::unwrap) {
|
|
// Success, store result into vector.
|
|
Ok(future) => Some(future.boxed()),
|
|
// Unknown failure.
|
|
Err(e) => panic!("failed to flush future: {e}"),
|
|
};
|
|
}
|
|
_ => {}
|
|
}
|
|
}
|
|
|
|
fn about_to_wait(&mut self, _event_loop: &ActiveEventLoop) {
|
|
let rcx = self.rcx.as_mut().unwrap();
|
|
rcx.window.request_redraw();
|
|
}
|
|
}
|
|
|
|
#[derive(BufferContents, Vertex)]
|
|
#[repr(C)]
|
|
struct MyVertex {
|
|
#[format(R32G32_SFLOAT)]
|
|
pos: [f32; 2],
|
|
#[format(R32G32_SFLOAT)]
|
|
vel: [f32; 2],
|
|
}
|
|
|
|
// Compute shader for updating the position and velocity of each particle every frame.
|
|
mod cs {
|
|
vulkano_shaders::shader! {
|
|
ty: "compute",
|
|
src: r"
|
|
#version 450
|
|
|
|
layout(local_size_x = 128, local_size_y = 1, local_size_z = 1) in;
|
|
|
|
struct VertexData {
|
|
vec2 pos;
|
|
vec2 vel;
|
|
};
|
|
|
|
// Storage buffer binding, which we optimize by using a DeviceLocalBuffer.
|
|
layout (binding = 0) buffer VertexBuffer {
|
|
VertexData vertices[];
|
|
};
|
|
|
|
// Allow push constants to define a parameters of compute.
|
|
layout (push_constant) uniform PushConstants {
|
|
vec2 attractor;
|
|
float attractor_strength;
|
|
float delta_time;
|
|
} push;
|
|
|
|
// Keep this value in sync with the `maxSpeed` const in the vertex shader.
|
|
const float maxSpeed = 10.0;
|
|
|
|
const float minLength = 0.02;
|
|
const float friction = -2.0;
|
|
|
|
void main() {
|
|
const uint index = gl_GlobalInvocationID.x;
|
|
|
|
vec2 vel = vertices[index].vel;
|
|
|
|
// Update particle position according to velocity.
|
|
vec2 pos = vertices[index].pos + push.delta_time * vel;
|
|
|
|
// Bounce particle off screen-border.
|
|
if (abs(pos.x) > 1.0) {
|
|
vel.x = sign(pos.x) * (-0.95 * abs(vel.x) - 0.0001);
|
|
if (abs(pos.x) >= 1.05) {
|
|
pos.x = sign(pos.x);
|
|
}
|
|
}
|
|
if (abs(pos.y) > 1.0) {
|
|
vel.y = sign(pos.y) * (-0.95 * abs(vel.y) - 0.0001);
|
|
if (abs(pos.y) >= 1.05) {
|
|
pos.y = sign(pos.y);
|
|
}
|
|
}
|
|
|
|
// Simple inverse-square force.
|
|
vec2 t = push.attractor - pos;
|
|
float r = max(length(t), minLength);
|
|
vec2 force = push.attractor_strength * (t / r) / (r * r);
|
|
|
|
// Update velocity, enforcing a maximum speed.
|
|
vel += push.delta_time * force;
|
|
if (length(vel) > maxSpeed) {
|
|
vel = maxSpeed*normalize(vel);
|
|
}
|
|
|
|
// Set new values back into buffer.
|
|
vertices[index].pos = pos;
|
|
vertices[index].vel = vel * exp(friction * push.delta_time);
|
|
}
|
|
",
|
|
}
|
|
}
|