extensions

README

vkngwrapper/extensions/v2

go get github.com/vkngwrapper/core/v2

Vkngwrapper (proununced "Viking Wrapper") is a handwritten cgo wrapper for the Vulkan graphics and compute API. The goal is to produce fast, easy-to-use, low-go-allocation, and idiomatic Go code to communicate with your graphics card and enable games and other graphical applications.

To learn more about how to use vkngwrapper, check out the core library. For the future roadmap, see the org page.

Using Extensions

Once you've gotten the hang of the core library, you may wish to make use of one of Vullkan's many extensions. This library provides first-class support for a small-but-growing list of Vulkan extensions. It's easy enough to use an extension: just like core 1.1 and core 1.2 in the core library, most of the contents of an extension are constants an structures, which can be accessed via the package name, such as khr_imageless_framebuffer.FramebufferAttachmentImageInfo or khr_sampler_mirror_clamp_to_edge.SamplerAddressModeMirrorClampToEdge.

For extensions that add new commands, you can create an extension object using CreateExtensionFromInstance for instance extensions, or CreateExtensionFromDevice for device extensions. Commands can be called on the new Extension object. These methods will return nil if the Instance or Device was not created with the extension in question active. For your convenience, ExtensionName constants, such as khr_external_memory.ExtensionName are provided for all extensions, which you can pass to Instance/Device creation.

Example:

	debugLoader := ext_debug_utils.CreateExtensionFromInstance(instance)
	debugMessenger, _, err := debugLoader.CreateDebugUtilsMessenger(instance, nil, ext_debug_utils.DebugUtilsMessengerCreateInfo{
      MessageSeverity: ext_debug_utils.SeverityError | ext_debug_utils.SeverityWarning,
      MessageType:     ext_debug_utils.TypeGeneral | ext_debug_utils.TypeValidation | ext_debug_utils.TypePerformance,
      UserCallback:    logValidationFunc,
    })
	if err != nil {
		return err
	}

Supporting Promoted Extensions

From time to time you may wish to use a particular piece of functionality added by a since-promoted extension if either the promoted core API version or the extension are present. But given that the two APIs are often different, how can that be easily done?

• For data structures such as Options or OutData, simply use the types from the core package.
• For extension functions, there should be a shim package included with the extension if the extension has callable Vulkan functions. This shim package includes a Shim interface that can be received and called from your code, as well as a NewShim function that allows you to pass in an extension and receive a Shim. The relevant core Vulkan object already satisfies the Shim interface.

For instance, khr_get_memory_requirements2_shim.Shim adds an interface met by core1_1.Device, and also adds a NewShim() method that accepts a khr_get_memory_requirements2.Extension and core1_0.Device and provides an object that satisfies Shim. By using a Shim object to interact with these methods, it is easy to interact with them in a flexible way.

Supported Extensions

• Three major extensions used by most applications developers: vk_ext_debug_utils, vk_khr_surface, and vk_khr_swapchain
• vk_khr_portability_subset and vk_khr_portability_enumeration, which can be used to add Mac/iOS support to your Vulkan applications
• 23 extensions which were promoted to core 1.1
• 24 extensions which were promoted to core 1.2

It's also easy to add support for new extensions! Feel free to contribute your favorite Vulkan extension!