Reimplement Vulkan shader objects. (#1764)

* Reimplement Vulkan shader objects.

This change reimplements Vulkan shader objects in the `gfx` layer so that it is no longer layered on top of the `DescriptorSet` abstraction. Since this is the last implementation that uses `DescriptorSet`, the change also removes all `DescriptorSet` related API from public `gfx` interface.

The Vulkan implementation now passes all test cases, but it still have two issues:
1. The PushConstant setting is not correct, this is because we don't seem to be able to get correct reflection data about the size of push constants for an entry-point.
2. The `shader-toy` example can't run on Vulkan, because it currently sets nullptr to `Texture` bindings, and this change doesn't properly handle setting resource to null in `ShaderObject`s yet. If we can use the `nullDescriptor` feature on vulkan, this implementation will be simple. However we still want to decide whether we want to use a Vulkan 1.2 feature for this.

* Fix up

1 files changed, 0 insertions, 7 deletions

diff --git a/tools/gfx/renderer-shared.h b/tools/gfx/renderer-shared.h
index 5ca5f064b..41b9a31c9 100644
--- a/tools/gfx/renderer-shared.h
+++ b/tools/gfx/renderer-shared.h
@@ -99,11 +99,6 @@ protected:
     Desc m_desc;
 };
 
-Result createProgramFromSlang(
-    IDevice* device,
-    IShaderProgram::Desc const& desc,
-    IShaderProgram** outProgram);
-
 class RendererBase;
 
 typedef uint32_t ShaderComponentID;
@@ -279,8 +274,6 @@ public:
     bool isSpecializable = false;
     ComPtr<IShaderProgram> m_program;
 
-    ComPtr<IPipelineLayout> m_pipelineLayout;
-
 protected:
     void initializeBase(const PipelineStateDesc& inDesc);
 };