From 85fa5425d91733201ca6f9a73cbf6e748976d309 Mon Sep 17 00:00:00 2001
From: Marijn Suijten <marijn@traverseresearch.nl>
Date: Sun, 5 Jun 2022 12:32:26 +0200
Subject: [PATCH] extensions/khr: Add VK_KHR_device_group_creation (#630)

---
 Changelog.md                                  |  1 +
 .../extensions/khr/device_group_creation.rs   | 62 +++++++++++++++++++
 ash/src/extensions/khr/mod.rs                 |  2 +
 3 files changed, 65 insertions(+)
 create mode 100644 ash/src/extensions/khr/device_group_creation.rs

diff --git a/Changelog.md b/Changelog.md
index 355131a..af9b41f 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -12,6 +12,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added `VK_EXT_sample_locations` device extension (#616)
 - Update Vulkan-Headers to 1.3.211 (#605, #608)
 - Added `VK_EXT_image_drm_format_modifier` device extension (#603)
+- Added `VK_KHR_device_group_creation` instance extension (#630)
 
 ### Removed
 
diff --git a/ash/src/extensions/khr/device_group_creation.rs b/ash/src/extensions/khr/device_group_creation.rs
new file mode 100644
index 0000000..f6c72b4
--- /dev/null
+++ b/ash/src/extensions/khr/device_group_creation.rs
@@ -0,0 +1,62 @@
+use crate::prelude::*;
+use crate::vk;
+use crate::{Entry, Instance};
+use std::ffi::CStr;
+use std::mem;
+use std::ptr;
+
+#[derive(Clone)]
+pub struct DeviceGroupCreation {
+    handle: vk::Instance,
+    fp: vk::KhrDeviceGroupCreationFn,
+}
+
+impl DeviceGroupCreation {
+    pub fn new(entry: Entry, instance: &Instance) -> Self {
+        let handle = instance.handle();
+        let fp = vk::KhrDeviceGroupCreationFn::load(|name| unsafe {
+            mem::transmute(entry.get_instance_proc_addr(handle, name.as_ptr()))
+        });
+        Self { handle, fp }
+    }
+
+    /// Retrieve the number of elements to pass to [`enumerate_physical_device_groups()`][Self::enumerate_physical_device_groups()]
+    #[inline]
+    pub unsafe fn enumerate_physical_device_groups_len(&self) -> VkResult<usize> {
+        let mut group_count = 0;
+        (self.fp.enumerate_physical_device_groups_khr)(
+            self.handle,
+            &mut group_count,
+            ptr::null_mut(),
+        )
+        .result_with_success(group_count as usize)
+    }
+
+    /// <https://www.khronos.org/registry/vulkan/specs/1.3-extensions/man/html/vkEnumeratePhysicalDeviceGroupsKHR.html>
+    ///
+    /// Call [`enumerate_physical_device_groups_len()`][Self::enumerate_physical_device_groups_len()] to query the number of elements to pass to `out`.
+    /// Be sure to [`Default::default()`]-initialize these elements and optionally set their `p_next` pointer.
+    #[inline]
+    pub unsafe fn enumerate_physical_device_groups(
+        &self,
+        out: &mut [vk::PhysicalDeviceGroupProperties],
+    ) -> VkResult<()> {
+        let mut count = out.len() as u32;
+        (self.fp.enumerate_physical_device_groups_khr)(self.handle, &mut count, out.as_mut_ptr())
+            .result()?;
+        assert_eq!(count as usize, out.len());
+        Ok(())
+    }
+
+    pub const fn name() -> &'static CStr {
+        vk::KhrDeviceGroupCreationFn::name()
+    }
+
+    pub fn fp(&self) -> &vk::KhrDeviceGroupCreationFn {
+        &self.fp
+    }
+
+    pub fn device(&self) -> vk::Instance {
+        self.handle
+    }
+}
diff --git a/ash/src/extensions/khr/mod.rs b/ash/src/extensions/khr/mod.rs
index 55f6e8e..fe1c5cf 100644
--- a/ash/src/extensions/khr/mod.rs
+++ b/ash/src/extensions/khr/mod.rs
@@ -4,6 +4,7 @@ pub use self::buffer_device_address::BufferDeviceAddress;
 pub use self::copy_commands2::CopyCommands2;
 pub use self::create_render_pass2::CreateRenderPass2;
 pub use self::deferred_host_operations::DeferredHostOperations;
+pub use self::device_group_creation::DeviceGroupCreation;
 pub use self::display::Display;
 pub use self::display_swapchain::DisplaySwapchain;
 pub use self::draw_indirect_count::DrawIndirectCount;
@@ -39,6 +40,7 @@ mod buffer_device_address;
 mod copy_commands2;
 mod create_render_pass2;
 mod deferred_host_operations;
+mod device_group_creation;
 mod display;
 mod display_swapchain;
 mod draw_indirect_count;