Support VK_KHR_push_descriptor (#241)

* Support VK_KHR_push_descriptor

* Accept slice in cmd_push_descriptor_set

ash/src/extensions/khr/mod.rs

@@ -1,6 +1,7 @@
 pub use self::android_surface::AndroidSurface;
 pub use self::display::Display;
 pub use self::display_swapchain::DisplaySwapchain;
+pub use self::push_descriptor::PushDescriptor;
 pub use self::surface::Surface;
 pub use self::swapchain::Swapchain;
 pub use self::wayland_surface::WaylandSurface;
@@ -11,6 +12,7 @@ pub use self::xlib_surface::XlibSurface;
 mod android_surface;
 mod display;
 mod display_swapchain;
+mod push_descriptor;
 mod surface;
 mod swapchain;
 mod wayland_surface;

ash/src/extensions/khr/push_descriptor.rs

@@ -0,0 +1,75 @@
+#![allow(dead_code)]
+use crate::version::{DeviceV1_0, InstanceV1_0};
+use crate::vk;
+use std::ffi::c_void;
+use std::ffi::CStr;
+use std::mem;
+
+#[derive(Clone)]
+pub struct PushDescriptor {
+    handle: vk::Instance,
+    push_descriptors_fn: vk::KhrPushDescriptorFn,
+}
+
+impl PushDescriptor {
+    pub fn new<I: InstanceV1_0, D: DeviceV1_0>(instance: &I, device: &D) -> PushDescriptor {
+        let push_descriptors_fn = vk::KhrPushDescriptorFn::load(|name| unsafe {
+            mem::transmute(instance.get_device_proc_addr(device.handle(), name.as_ptr()))
+        });
+
+        PushDescriptor {
+            handle: instance.handle(),
+            push_descriptors_fn,
+        }
+    }
+
+    pub fn name() -> &'static CStr {
+        vk::KhrPushDescriptorFn::name()
+    }
+
+    #[doc = "<https://www.khronos.org/registry/vulkan/specs/1.1-extensions/html/vkspec.html#vkCmdPushDescriptorSetKHR>"]
+    pub unsafe fn cmd_push_descriptor_set(
+        &self,
+        command_buffer: vk::CommandBuffer,
+        pipeline_bind_point: vk::PipelineBindPoint,
+        layout: vk::PipelineLayout,
+        set: u32,
+        descriptor_writes: &[vk::WriteDescriptorSet],
+    ) {
+        self.push_descriptors_fn.cmd_push_descriptor_set_khr(
+            command_buffer,
+            pipeline_bind_point,
+            layout,
+            set,
+            descriptor_writes.len() as u32,
+            descriptor_writes.as_ptr(),
+        );
+    }
+
+    #[doc = "<https://www.khronos.org/registry/vulkan/specs/1.1-extensions/html/vkspec.html#vkCmdPushDescriptorSetWithTemplateKHR>"]
+    pub unsafe fn cmd_push_descriptor_set_with_template(
+        &self,
+        command_buffer: vk::CommandBuffer,
+        descriptor_update_template: vk::DescriptorUpdateTemplate,
+        layout: vk::PipelineLayout,
+        set: u32,
+        p_data: *const c_void,
+    ) {
+        self.push_descriptors_fn
+            .cmd_push_descriptor_set_with_template_khr(
+                command_buffer,
+                descriptor_update_template,
+                layout,
+                set,
+                p_data,
+            );
+    }
+
+    pub fn fp(&self) -> &vk::KhrPushDescriptorFn {
+        &self.push_descriptors_fn
+    }
+
+    pub fn instance(&self) -> vk::Instance {
+        self.handle
+    }
+}