First pass support for half on vk (#912)

* Look at getting half to work on vk.

* Alter half test so can always produce consistent test results.

* First pass working half on vk.

* Improve comments for vulkan extensions around half.

* Upgraded vulkan headers to v1.1.103

https://github.com/KhronosGroup/Vulkan-Headers

* * Add getFeatures on Render interface
* Vulkan renderer determines at startup if it can support half
* Parse render-features on render-test

* Small changes to half-calc.slang test.

* Structured buffer half access works as expected for Vk, but isn't for dx12, so disable for now.

* Require the half feature for renderers for the half-structured-buffer.slang test.

* * Added ToolReturnCode to be more rigerous about how a return code is passed back from a tool
* Added support for a tool being able to pass back an 'ignored' result.
* Used enum codes to indicate meanings
* Made spawnAndWait return a ToolReturnCode

* Ignore tests that don't have required render-feature

* Fix macro line continuation usage.

* Check dx12 has half support.

* Checking for half on dx12 - if CheckFeatureSupport fails, don't fail renderer initialization.

* Fix typo.

1 files changed, 4 insertions, 0 deletions

diff --git a/tools/gfx/vk-api.cpp b/tools/gfx/vk-api.cpp
index 4030e43ba..6e250e281 100644
--- a/tools/gfx/vk-api.cpp
+++ b/tools/gfx/vk-api.cpp
@@ -49,11 +49,15 @@ Slang::Result VulkanApi::initInstanceProcs(VkInstance instance)
 
     VK_API_ALL_INSTANCE_PROCS(VK_API_GET_INSTANCE_PROC)
 
+    // Get optional 
+    VK_API_INSTANCE_PROCS_OPT(VK_API_GET_INSTANCE_PROC)
+
     if (!areDefined(ProcType::Instance))
     {
         return SLANG_FAIL;
     }
 
+
     m_instance = instance;
     return SLANG_OK;
 }