vulkano/examples/runtime-shader/main.rs

// Copyright (c) 2017 The vulkano developers
// Licensed under the Apache License, Version 2.0
// <LICENSE-APACHE or
// https://www.apache.org/licenses/LICENSE-2.0> or the MIT
// license <LICENSE-MIT or https://opensource.org/licenses/MIT>,
// at your option. All files in the project carrying such
// notice may not be copied, modified, or distributed except
// according to those terms.

// This example demonstrates one way of preparing data structures and loading SPIRV shaders from
// external source (file system).
//
// Note that you will need to do all correctness checking yourself.
//
// `vert.glsl` and `frag.glsl` must be built by you. One way of building them is to use `shaderc`:
//
// ```bash
// glslc -fshader-stage=vert vert.glsl -o vert.spv
// glslc -fshader-stage=frag frag.glsl -o frag.spv
// ```
//
// Vulkano uses shaderc to build your shaders internally.

use std::{fs::File, io::Read, path::Path, sync::Arc};
use vulkano::{
    buffer::{Buffer, BufferContents, BufferCreateInfo, BufferUsage},
    command_buffer::{
        allocator::StandardCommandBufferAllocator, AutoCommandBufferBuilder, CommandBufferUsage,
        RenderPassBeginInfo,
    },
    device::{
        physical::PhysicalDeviceType, Device, DeviceCreateInfo, DeviceExtensions, QueueCreateInfo,
        QueueFlags,
    },
    image::{view::ImageView, Image, ImageUsage},
    instance::{Instance, InstanceCreateFlags, InstanceCreateInfo},
    memory::allocator::{AllocationCreateInfo, MemoryTypeFilter, StandardMemoryAllocator},
    pipeline::{
        graphics::{
            color_blend::{ColorBlendAttachmentState, ColorBlendState},
            input_assembly::InputAssemblyState,
            multisample::MultisampleState,
            rasterization::{CullMode, FrontFace, RasterizationState},
            vertex_input::{Vertex, VertexDefinition},
            viewport::{Viewport, ViewportState},
            GraphicsPipelineCreateInfo,
        },
        layout::PipelineDescriptorSetLayoutCreateInfo,
        DynamicState, GraphicsPipeline, PipelineLayout, PipelineShaderStageCreateInfo,
    },
    render_pass::{Framebuffer, FramebufferCreateInfo, RenderPass, Subpass},
    shader::{ShaderModule, ShaderModuleCreateInfo},
    swapchain::{
        acquire_next_image, Surface, Swapchain, SwapchainCreateInfo, SwapchainPresentInfo,
    },
    sync::{self, GpuFuture},
    Validated, VulkanError, VulkanLibrary,
};
use winit::{
    event::{Event, WindowEvent},
    event_loop::{ControlFlow, EventLoop},
    window::WindowBuilder,
};

fn main() {
    let event_loop = EventLoop::new();

    let library = VulkanLibrary::new().unwrap();
    let required_extensions = Surface::required_extensions(&event_loop);
    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, queue_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,
    );

    let (device, mut queues) = Device::new(
        physical_device,
        DeviceCreateInfo {
            enabled_extensions: device_extensions,
            queue_create_infos: vec![QueueCreateInfo {
                queue_family_index,
                ..Default::default()
            }],
            ..Default::default()
        },
    )
    .unwrap();
    let queue = queues.next().unwrap();

    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 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 graphics_pipeline = {
        let vs = {
            let code = read_spirv_words_from_file("vert.spv");

            // Create a ShaderModule on a device the same Shader::load does it.
            // NOTE: You will have to verify correctness of the data by yourself!
            let module = unsafe {
                ShaderModule::new(device.clone(), ShaderModuleCreateInfo::new(&code)).unwrap()
            };
            module.entry_point("main").unwrap()
        };

        let fs = {
            let code = read_spirv_words_from_file("frag.spv");

            let module = unsafe {
                ShaderModule::new(device.clone(), ShaderModuleCreateInfo::new(&code)).unwrap()
            };
            module.entry_point("main").unwrap()
        };

        let vertex_input_state = Vertex::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::default()),
                viewport_state: Some(ViewportState::default()),
                rasterization_state: Some(RasterizationState {
                    cull_mode: CullMode::Front,
                    front_face: FrontFace::CounterClockwise,
                    ..Default::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 recreate_swapchain = false;

    let memory_allocator = Arc::new(StandardMemoryAllocator::new_default(device.clone()));

    #[derive(BufferContents, Vertex)]
    #[repr(C)]
    pub struct Vertex {
        #[format(R32G32_SFLOAT)]
        pub position: [f32; 2],
        #[format(R32G32B32_SFLOAT)]
        pub color: [f32; 3],
    }

    let vertices = [
        Vertex {
            position: [-1.0, 1.0],
            color: [1.0, 0.0, 0.0],
        },
        Vertex {
            position: [0.0, -1.0],
            color: [0.0, 1.0, 0.0],
        },
        Vertex {
            position: [1.0, 1.0],
            color: [0.0, 0.0, 1.0],
        },
    ];
    let vertex_buffer = Buffer::from_iter(
        memory_allocator,
        BufferCreateInfo {
            usage: BufferUsage::VERTEX_BUFFER,
            ..Default::default()
        },
        AllocationCreateInfo {
            memory_type_filter: MemoryTypeFilter::PREFER_DEVICE
                | MemoryTypeFilter::HOST_SEQUENTIAL_WRITE,
            ..Default::default()
        },
        vertices,
    )
    .unwrap();

    // NOTE: We don't create any descriptor sets in this example, but you should
    // note that passing wrong types, providing sets at wrong indexes will cause
    // descriptor set builder to return Err!
    // TODO: Outdated ^

    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 mut previous_frame_end = Some(sync::now(device.clone()).boxed());

    let command_buffer_allocator =
        StandardCommandBufferAllocator::new(device.clone(), Default::default());

    event_loop.run(move |event, _, control_flow| match event {
        Event::WindowEvent {
            event: WindowEvent::CloseRequested,
            ..
        } => {
            *control_flow = ControlFlow::Exit;
        }
        Event::WindowEvent {
            event: WindowEvent::Resized(_),
            ..
        } => {
            recreate_swapchain = true;
        }
        Event::RedrawEventsCleared => {
            let image_extent: [u32; 2] = window.inner_size().into();

            if image_extent.contains(&0) {
                return;
            }

            previous_frame_end.as_mut().unwrap().cleanup_finished();

            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 = AutoCommandBufferBuilder::primary(
                &command_buffer_allocator,
                queue.queue_family_index(),
                CommandBufferUsage::MultipleSubmit,
            )
            .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(graphics_pipeline.clone())
                .unwrap()
                .bind_vertex_buffers(0, vertex_buffer.clone())
                .unwrap()
                .draw(vertex_buffer.len() as u32, 1, 0, 0)
                .unwrap()
                .end_render_pass(Default::default())
                .unwrap();
            let command_buffer = builder.build().unwrap();

            let future = previous_frame_end
                .take()
                .unwrap()
                .join(acquire_future)
                .then_execute(queue.clone(), command_buffer)
                .unwrap()
                .then_swapchain_present(
                    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());
                }
            }
        }
        _ => (),
    });
}

/// 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<_>>()
}

fn read_spirv_words_from_file(path: impl AsRef<Path>) -> Vec<u32> {
    // Read the file.
    let path = path.as_ref();
    let mut bytes = vec![];
    let path = Path::new(env!("CARGO_MANIFEST_DIR")).join(path);
    let mut file = File::open(&path).unwrap();
    file.read_to_end(&mut bytes).unwrap();

    vulkano::shader::spirv::bytes_to_words(&bytes)
        .unwrap_or_else(|err| panic!("file `{}`: {}", path.display(), err))
        .into_owned()
}