A very lightweight wrapper around Vulkan
No.
ResultFunctions return a type VkResult<T> = Result<T, vk::Result> instead of an error code. No mutable references for the output are required.
Rust
pub fn create_swapchain_khr(&self,
create_info: &vk::SwapchainCreateInfoKHR)
-> VkResult<vk::SwapchainKHR>;
let swapchain = device.create_swapchain_khr(&swapchain_create_info).unwrap();
Always returns a Vec<T> for functions that output multiple values.
Rust
pub fn get_swapchain_images_khr(&self,
swapchain: vk::SwapchainKHR)
-> VkResult<Vec<vk::Image>>;
let present_images = device.get_swapchain_images_khr(swapchain).unwrap();
Ash always uses slices in functions. ```Rust // C void vkCmdPipelineBarrier( VkCommandBuffer commandBuffer, VkPipelineStageFlags srcStageMask, VkPipelineStageFlags dstStageMask, VkDependencyFlags dependencyFlags, uint32t memoryBarrierCount, const VkMemoryBarrier* pMemoryBarriers, uint32t bufferMemoryBarrierCount, const VkBufferMemoryBarrier* pBufferMemoryBarriers, uint32_t imageMemoryBarrierCount, const VkImageMemoryBarrier* pImageMemoryBarriers);
// Rust pub fn cmdpipelinebarrier(&self, commandbuffer: vk::CommandBuffer, srcstagemask: vk::PipelineStageFlags, dststagemask: vk::PipelineStageFlags, dependencyflags: vk::DependencyFlags, memorybarriers: &[vk::MemoryBarrier], buffermemorybarriers: &[vk::BufferMemoryBarrier], imagememory_barriers: &[vk::ImageMemoryBarrier]);
device.cmdpipelinebarrier(setupcommandbuffer, vk::PIPELINESTAGETOPOFPIPEBIT, vk::PIPELINESTAGETOPOFPIPEBIT, vk::DependencyFlags::empty(), &[], &[], &[layouttransitionbarrier]);
// or
let slice = device.mapmemory::
Ash still uses raw Vulkan structs. The only difference is type safety. Everything that can be an enum is an enum like vk::StructureType, flags are implemented similar to the Bitflags crate. Ash also follows the Rust style guide. The reason that Ash uses raw Vulkan structs is to be extensible, just like the Vulkan spec.
Rust
let pool_create_info = vk::CommandPoolCreateInfo {
s_type: vk::StructureType::CommandPoolCreateInfo,
p_next: ptr::null(),
flags: vk::COMMAND_POOL_CREATE_RESET_COMMAND_BUFFER_BIT,
queue_family_index: queue_family_index,
};
let pool = device.create_command_pool(&pool_create_info).unwrap();
Additionally pointers like Instance, Device, Queue etc are hidden behind a type. Those pointers can only be constructed from within Ash which elimites invalid API usage and has the benefit of making some functions in Vulkan safe.
Ash also takes care of loading the function pointers. Function pointers are split into 3 categories. Entry, Instance and Device. The reason for not loading it into a global is that in Vulkan you can have multiple devices and each device must load its own function pointers.
Rust
// Looks for the vulkan lib in your path, alternatively you can supply the path explicitly.
let entry = Entry::load_vulkan().unwrap();
let instance: Instance = entry.create_instance(&create_info).expect("Instance creation error");
let device: Device = instance.create_device(pdevice, &device_create_info)
.unwrap();
Additionally, every Vulkan extension has to be loaded explicity. You can find all extensions under ash::extensions. You still have to tell Vulkan which instance or device extensions you want to load.
Rust
use ash::extensions::Swapchain;
let swapchain_loader = Swapchain::new(&instance, &device).expect("Unable to load swapchain");
let swapchain = swapchain_loader.create_swapchain_khr(&swapchain_create_info).unwrap();
You don't have to pass an Instance or Device handle anymore, this is done implicitly for you. ```Rust // C VkResult vkCreateCommandPool( VkDevice device, const VkCommandPoolCreateInfo* pCreateInfo, const VkAllocationCallbacks* pAllocator, VkCommandPool* pCommandPool);
// Rust
pub fn createcommandpool(&self,
create_info: &vk::CommandPoolCreateInfo)
-> VkResult
let pool = device.createcommandpool(&poolcreateinfo).unwrap(); ```
```Rust use ash::extensions::{Swapchain, XlibSurface, Surface, DebugReport};
fn extensionnames() -> Vec<*const i8> { vec![ Surface::name().asptr(), XlibSurface::name().asptr(), DebugReport::name().asptr() ] } ```
You can find the examples here.
All examples currently require: the LunarG Validation layers and a Vulkan library that is visible in your PATH.
Displays a triangle with vertex colors.
cd examples
cargo run --bin triangle
Displays a texture on a quad.
cd examples
cargo run --bin texture
