Merge pull request #451 from cdavis5e/amd-gpu-shader-half-float

Advertise the VK_AMD_gpu_shader_half_float extension.
diff --git a/Docs/MoltenVK_Runtime_UserGuide.md b/Docs/MoltenVK_Runtime_UserGuide.md
index 4037632..6830345 100644
--- a/Docs/MoltenVK_Runtime_UserGuide.md
+++ b/Docs/MoltenVK_Runtime_UserGuide.md
@@ -247,6 +247,7 @@
 - `VK_MVK_macos_surface` (macOS)
 - `VK_MVK_ios_surface` (iOS)
 - `VK_MVK_moltenvk`
+- `VK_AMD_gpu_shader_half_float`
 - `VK_AMD_negative_viewport_height`
 - `VK_IMG_format_pvrtc` (iOS)
 
diff --git a/Docs/Whats_New.md b/Docs/Whats_New.md
index 8e186a6..83a9675 100644
--- a/Docs/Whats_New.md
+++ b/Docs/Whats_New.md
@@ -16,7 +16,7 @@
 MoltenVK 1.0.31
 ---------------
 
-Released 2018/01/15
+Released 2019/01/15
 
 - Support runtime config via runtime environment variables
 - Add full ImageView swizzling to config, and disable it by default.
@@ -29,6 +29,7 @@
 - Log Vulkan versions in human readable form when reporting version error.
 - Update `VK_MVK_MOLTENVK_SPEC_VERSION` to 16.
 - Update copyright to 2019.
+- Advertise the `VK_AMD_gpu_shader_half_float` extension.
 - Update to latest SPIRV-Cross version:
 	- MSL: Support SPV_KHR_variable_pointers.
 	- MSL: Workaround missing gradient2d() on macOS for typical cascaded shadow mapping.
diff --git a/MoltenVK/MoltenVK/Layers/MVKExtensions.def b/MoltenVK/MoltenVK/Layers/MVKExtensions.def
index a600ff9..7746de1 100644
--- a/MoltenVK/MoltenVK/Layers/MVKExtensions.def
+++ b/MoltenVK/MoltenVK/Layers/MVKExtensions.def
@@ -55,6 +55,7 @@
 MVK_EXTENSION(MVK_ios_surface, MVK_IOS_SURFACE)
 MVK_EXTENSION(MVK_macos_surface, MVK_MACOS_SURFACE)
 MVK_EXTENSION(MVK_moltenvk, MVK_MOLTENVK)
+MVK_EXTENSION(AMD_gpu_shader_half_float, AMD_GPU_SHADER_HALF_FLOAT)
 MVK_EXTENSION(AMD_negative_viewport_height, AMD_NEGATIVE_VIEWPORT_HEIGHT)
 MVK_EXTENSION_LAST(IMG_format_pvrtc, IMG_FORMAT_PVRTC)