mirror of
https://github.com/vulkano-rs/vulkano.git
synced 2024-11-22 06:45:23 +00:00
582 lines
21 KiB
Rust
582 lines
21 KiB
Rust
// Indirect draw example
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//
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// Indirect draw calls allow us to issue a draw without needing to know the number of vertices
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// until later when the draw is executed by the GPU.
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//
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// This is used in situations where vertices are being generated on the GPU, such as a GPU particle
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// simulation, and the exact number of output vertices cannot be known until the compute shader has
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// run.
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//
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// In this example the compute shader is trivial and the number of vertices does not change.
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// However is does demonstrate that each compute instance atomically updates the vertex counter
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// before filling the vertex buffer.
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//
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// For an explanation of how the rendering of the triangles takes place see the `triangle.rs`
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// example.
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use std::{error::Error, sync::Arc};
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use vulkano::{
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buffer::{
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allocator::{SubbufferAllocator, SubbufferAllocatorCreateInfo},
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BufferContents, BufferUsage,
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},
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command_buffer::{
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allocator::StandardCommandBufferAllocator, CommandBufferBeginInfo, CommandBufferLevel,
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CommandBufferUsage, DrawIndirectCommand, RecordingCommandBuffer, 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, QueueCreateInfo,
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QueueFlags,
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},
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image::{view::ImageView, Image, ImageUsage},
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instance::{Instance, InstanceCreateFlags, InstanceCreateInfo},
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memory::allocator::{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,
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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, DynamicState, GraphicsPipeline, Pipeline, PipelineBindPoint,
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PipelineLayout, PipelineShaderStageCreateInfo,
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},
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render_pass::{Framebuffer, FramebufferCreateInfo, RenderPass, Subpass},
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single_pass_renderpass,
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swapchain::{
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acquire_next_image, Surface, Swapchain, SwapchainCreateInfo, SwapchainPresentInfo,
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},
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sync::{self, GpuFuture},
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Validated, VulkanError, VulkanLibrary,
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};
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use winit::{
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event::{Event, WindowEvent},
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event_loop::{ControlFlow, EventLoop},
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window::WindowBuilder,
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};
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fn main() -> Result<(), impl Error> {
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let event_loop = EventLoop::new().unwrap();
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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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flags: InstanceCreateFlags::ENUMERATE_PORTABILITY,
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enabled_extensions: required_extensions,
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..Default::default()
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},
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)
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.unwrap();
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let window = Arc::new(WindowBuilder::new().build(&event_loop).unwrap());
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let surface = Surface::from_window(instance.clone(), window.clone()).unwrap();
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let device_extensions = DeviceExtensions {
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khr_swapchain: true,
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khr_storage_buffer_storage_class: 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.surface_support(i as u32, &surface).unwrap_or(false)
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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 (mut swapchain, images) = {
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let surface_capabilities = 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 = 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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.0;
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Swapchain::new(
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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.inner_size().into(),
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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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..Default::default()
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},
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)
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.unwrap()
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};
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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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// The triangle vertex positions.
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layout(location = 0) in vec2 position;
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void main() {
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gl_Position = vec4(position, 0.0, 1.0);
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}
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",
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}
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}
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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) out vec4 f_color;
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void main() {
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f_color = vec4(1.0, 0.0, 0.0, 1.0);
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}
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"#,
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}
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}
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// A simple compute shader that generates vertices. It has two buffers bound: the first is
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// where we output the vertices, the second is the `IndirectDrawArgs` struct we passed the
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// `draw_indirect` so we can set the number to vertices to draw.
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mod cs {
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vulkano_shaders::shader! {
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ty: "compute",
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src: r"
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#version 450
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layout(local_size_x = 16, local_size_y = 1, local_size_z = 1) in;
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layout(set = 0, binding = 0) buffer Output {
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vec2 pos[];
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} triangles;
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layout(set = 0, binding = 1) buffer IndirectDrawArgs {
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uint vertices;
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uint unused0;
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uint unused1;
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uint unused2;
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};
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void main() {
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uint idx = gl_GlobalInvocationID.x;
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// Each invocation of the compute shader is going to increment the counter, so
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// we need to use atomic operations for safety. The previous value of the
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// counter is returned so that gives us the offset into the vertex buffer this
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// thread can write it's vertices into.
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uint offset = atomicAdd(vertices, 6);
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vec2 center = vec2(-0.8, -0.8) + idx * vec2(0.1, 0.1);
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triangles.pos[offset + 0] = center + vec2(0.0, 0.0375);
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triangles.pos[offset + 1] = center + vec2(0.025, -0.01725);
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triangles.pos[offset + 2] = center + vec2(-0.025, -0.01725);
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triangles.pos[offset + 3] = center + vec2(0.0, -0.0375);
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triangles.pos[offset + 4] = center + vec2(0.025, 0.01725);
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triangles.pos[offset + 5] = center + vec2(-0.025, 0.01725);
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}
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",
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}
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}
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let memory_allocator = Arc::new(StandardMemoryAllocator::new_default(device.clone()));
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// Each frame we generate a new set of vertices and each frame we need a new
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// DrawIndirectCommand struct to set the number of vertices to draw.
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let indirect_args_pool = SubbufferAllocator::new(
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memory_allocator.clone(),
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SubbufferAllocatorCreateInfo {
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buffer_usage: BufferUsage::INDIRECT_BUFFER | BufferUsage::STORAGE_BUFFER,
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memory_type_filter: MemoryTypeFilter::PREFER_DEVICE
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| MemoryTypeFilter::HOST_SEQUENTIAL_WRITE,
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..Default::default()
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},
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);
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let vertex_pool = SubbufferAllocator::new(
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memory_allocator,
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SubbufferAllocatorCreateInfo {
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buffer_usage: BufferUsage::STORAGE_BUFFER | BufferUsage::VERTEX_BUFFER,
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memory_type_filter: MemoryTypeFilter::PREFER_DEVICE
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| MemoryTypeFilter::HOST_SEQUENTIAL_WRITE,
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..Default::default()
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},
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);
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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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let render_pass = single_pass_renderpass!(
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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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// `Vertex` is the vertex type that will be output from the compute shader and be input to the
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// vertex shader.
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#[derive(BufferContents, Vertex)]
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#[repr(C)]
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struct Vertex {
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#[format(R32G32_SFLOAT)]
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position: [f32; 2],
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}
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let render_pipeline = {
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let vs = vs::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 fs = fs::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 vertex_input_state = Vertex::per_vertex()
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.definition(&vs.info().input_interface)
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.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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device.clone(),
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PipelineDescriptorSetLayoutCreateInfo::from_stages(&stages)
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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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let subpass = Subpass::from(render_pass.clone(), 0).unwrap();
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GraphicsPipeline::new(
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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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input_assembly_state: Some(InputAssemblyState::default()),
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viewport_state: Some(ViewportState::default()),
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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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dynamic_state: [DynamicState::Viewport].into_iter().collect(),
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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 mut viewport = Viewport {
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offset: [0.0, 0.0],
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extent: [0.0, 0.0],
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depth_range: 0.0..=1.0,
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};
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let mut framebuffers = window_size_dependent_setup(&images, render_pass.clone(), &mut viewport);
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let mut recreate_swapchain = false;
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let mut previous_frame_end = Some(sync::now(device.clone()).boxed());
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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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event_loop.run(move |event, elwt| {
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elwt.set_control_flow(ControlFlow::Poll);
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match event {
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Event::WindowEvent {
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event: WindowEvent::CloseRequested,
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..
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} => {
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elwt.exit();
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}
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Event::WindowEvent {
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event: WindowEvent::Resized(_),
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..
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} => {
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recreate_swapchain = true;
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}
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Event::WindowEvent {
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event: WindowEvent::RedrawRequested,
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..
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} => {
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let image_extent: [u32; 2] = window.inner_size().into();
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if image_extent.contains(&0) {
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return;
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}
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previous_frame_end.as_mut().unwrap().cleanup_finished();
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if recreate_swapchain {
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let (new_swapchain, new_images) = swapchain
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.recreate(SwapchainCreateInfo {
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image_extent,
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..swapchain.create_info()
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})
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.expect("failed to recreate swapchain");
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swapchain = new_swapchain;
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framebuffers = window_size_dependent_setup(
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&new_images,
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render_pass.clone(),
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&mut viewport,
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);
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recreate_swapchain = false;
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}
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let (image_index, suboptimal, acquire_future) =
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match acquire_next_image(swapchain.clone(), None).map_err(Validated::unwrap) {
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Ok(r) => r,
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Err(VulkanError::OutOfDate) => {
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recreate_swapchain = true;
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return;
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}
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Err(e) => panic!("failed to acquire next image: {e}"),
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};
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if suboptimal {
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recreate_swapchain = true;
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}
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// Allocate a buffer to hold the arguments for this frame's draw call. The compute
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// shader will only update `vertex_count`, so set the other parameters correctly
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// here.
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let indirect_commands = [DrawIndirectCommand {
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vertex_count: 0,
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instance_count: 1,
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first_vertex: 0,
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first_instance: 0,
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}];
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let indirect_buffer = indirect_args_pool
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.allocate_slice(indirect_commands.len() as _)
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.unwrap();
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indirect_buffer
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.write()
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.unwrap()
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.copy_from_slice(&indirect_commands);
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|
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// Allocate a buffer to hold this frame's vertices. This needs to be large enough
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// to hold the worst case number of vertices generated by the compute shader.
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let iter = (0..(6 * 16)).map(|_| Vertex { position: [0.0; 2] });
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let vertices = vertex_pool.allocate_slice(iter.len() as _).unwrap();
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for (o, i) in vertices.write().unwrap().iter_mut().zip(iter) {
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*o = i;
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}
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|
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// Pass the two buffers to the compute shader.
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let layout = &compute_pipeline.layout().set_layouts()[0];
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let cs_desciptor_set = DescriptorSet::new(
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descriptor_set_allocator.clone(),
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layout.clone(),
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[
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WriteDescriptorSet::buffer(0, vertices.clone()),
|
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WriteDescriptorSet::buffer(1, indirect_buffer.clone()),
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],
|
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[],
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)
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.unwrap();
|
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|
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let mut builder = RecordingCommandBuffer::new(
|
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command_buffer_allocator.clone(),
|
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queue.queue_family_index(),
|
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CommandBufferLevel::Primary,
|
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CommandBufferBeginInfo {
|
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usage: CommandBufferUsage::OneTimeSubmit,
|
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..Default::default()
|
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},
|
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)
|
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.unwrap();
|
|
|
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// First in the command buffer we dispatch the compute shader to generate the
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// vertices and fill out the draw call arguments.
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builder
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.bind_pipeline_compute(compute_pipeline.clone())
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.unwrap()
|
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.bind_descriptor_sets(
|
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PipelineBindPoint::Compute,
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compute_pipeline.layout().clone(),
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0,
|
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cs_desciptor_set,
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)
|
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.unwrap();
|
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|
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unsafe {
|
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builder.dispatch([1, 1, 1]).unwrap();
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}
|
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|
|
builder
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.begin_render_pass(
|
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RenderPassBeginInfo {
|
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clear_values: vec![Some([0.0, 0.0, 1.0, 1.0].into())],
|
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..RenderPassBeginInfo::framebuffer(
|
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framebuffers[image_index as usize].clone(),
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)
|
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},
|
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Default::default(),
|
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)
|
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.unwrap()
|
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.set_viewport(0, [viewport.clone()].into_iter().collect())
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.unwrap()
|
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.bind_pipeline_graphics(render_pipeline.clone())
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.unwrap()
|
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.bind_vertex_buffers(0, vertices)
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.unwrap();
|
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|
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unsafe {
|
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// The indirect draw call is placed in the command buffer with a reference to
|
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// the buffer that will contain the arguments for the draw.
|
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builder.draw_indirect(indirect_buffer).unwrap();
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}
|
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|
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builder.end_render_pass(Default::default()).unwrap();
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|
|
let command_buffer = builder.end().unwrap();
|
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|
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let future = previous_frame_end
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.take()
|
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.unwrap()
|
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.join(acquire_future)
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.then_execute(queue.clone(), command_buffer)
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.unwrap()
|
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.then_swapchain_present(
|
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queue.clone(),
|
|
SwapchainPresentInfo::swapchain_image_index(swapchain.clone(), image_index),
|
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)
|
|
.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(),
|
|
_ => (),
|
|
}
|
|
})
|
|
}
|
|
|
|
/// 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<_>>()
|
|
}
|