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, 47 insertions, 0 deletions

diff --git a/tools/gfx/vulkan/vk-util.cpp b/tools/gfx/vulkan/vk-util.cpp
index 218801d7a..46ffb01fd 100644
--- a/tools/gfx/vulkan/vk-util.cpp
+++ b/tools/gfx/vulkan/vk-util.cpp
@@ -30,6 +30,53 @@ namespace gfx {
     return (res == VK_SUCCESS) ? SLANG_OK : SLANG_FAIL;
 }
 
+VkShaderStageFlags VulkanUtil::getShaderStage(SlangStage stage)
+{
+    switch (stage)
+    {
+    case SLANG_STAGE_ANY_HIT:
+        return VK_SHADER_STAGE_ANY_HIT_BIT_KHR;
+    case SLANG_STAGE_CALLABLE:
+        return VK_SHADER_STAGE_CALLABLE_BIT_KHR;
+    case SLANG_STAGE_CLOSEST_HIT:
+        return VK_SHADER_STAGE_CLOSEST_HIT_BIT_KHR;
+    case SLANG_STAGE_COMPUTE:
+        return VK_SHADER_STAGE_COMPUTE_BIT;
+    case SLANG_STAGE_DOMAIN:
+        return VK_SHADER_STAGE_TESSELLATION_CONTROL_BIT;
+    case SLANG_STAGE_FRAGMENT:
+        return VK_SHADER_STAGE_FRAGMENT_BIT;
+    case SLANG_STAGE_GEOMETRY:
+        return VK_SHADER_STAGE_GEOMETRY_BIT;
+    case SLANG_STAGE_HULL:
+        return VK_SHADER_STAGE_TESSELLATION_EVALUATION_BIT;
+    case SLANG_STAGE_INTERSECTION:
+        return VK_SHADER_STAGE_INTERSECTION_BIT_KHR;
+    case SLANG_STAGE_RAY_GENERATION:
+        return VK_SHADER_STAGE_RAYGEN_BIT_KHR;
+    case SLANG_STAGE_VERTEX:
+        return VK_SHADER_STAGE_VERTEX_BIT;
+    default:
+        assert(!"unsupported stage.");
+        return VkShaderStageFlags(-1);
+    }
+}
+
+VkPipelineBindPoint VulkanUtil::getPipelineBindPoint(PipelineType pipelineType)
+{
+    switch (pipelineType)
+    {
+    case gfx::PipelineType::Graphics:
+        return VK_PIPELINE_BIND_POINT_GRAPHICS;
+    case gfx::PipelineType::Compute:
+        return VK_PIPELINE_BIND_POINT_COMPUTE;
+    case gfx::PipelineType::RayTracing:
+        return VK_PIPELINE_BIND_POINT_RAY_TRACING_KHR;
+    default:
+        return VkPipelineBindPoint(-1);
+    }
+}
+
 /* static */Slang::Result VulkanUtil::handleFail(VkResult res)
 {
     if (res != VK_SUCCESS)