Autodesk: [hgi*] device filter

[erikaharrison-adsk]

Description of Change(s)

• Fix usage of Hgi in UsdImagingGLEngine.
  • It was mostly ignoring a user provided Hgi instance.
• Add HgiDeviceFilter which lets you hook into the Hgi instance and/or device selection and creation.
  • This can be used implementation agnostic, but limits you information exposed by the HgiCapabilities API.
    • If you link against a specific Hgi implementation, then you can downcast to the backend class, which might expose more API specific information (especially the case with Vulkan).
  • To hook into the creation arguments, you insteead need to implement the backend specific subinterface of HgiDeviceFilter. Those unlock the full power of the API.
  • Since the OpenGL context (the closest thing it has to a device) is created externally, it ignores the device filter result (with a warning). It only ever enumerates a single device, and it should have already been setup by the application.

Examples:

class UmaHgiDeviceFilter : public HgiDeviceFilter
{
public:
   ~UmaHgiDeviceFilter() override = default;

   bool FilterDevice(const HgiCapabilities& capabilities) override
   {
      return capabilities.IsSet(HgiDeviceCapabilitiesBitsUnifiedMemory);
   }
};

class SoftwareVkHgiDeviceFilter : public HgiDeviceFilter
{
public:
   ~SoftwareVkHgiDeviceFilter() override = default;

   const TfToken& GetTargetHgiName() const override
   {
      return HgiTokens->Vulkan;
   }

   bool FilterDevice(const HgiCapabilities& capabilities) override
   {
      return dynamic_cast<const HgiVulkanCapabilities*>(&capabilities)->vkDeviceProperties2.properties.deviceType == VK_PHYSICAL_DEVICE_TYPE_CPU;
   }
};

class FixMoltenVkHgiDeviceFitler : public HgiVulkanDeviceFilter
{
public:
   ~FixMoltenVkHgiDeviceFitler() override = default;

   bool FilterDevice(const HgiVulkanCapabilities& capabilities,
        VkPhysicalDevice device, VkDeviceCreateInfo& info) override
   {
      static constexpr uint32_t appleVendorID = 0x106B;
      if (capabilities.vkDeviceProperties2.properties.vendorID == appleVendorID) {
         // Disable host image copy on MoltenVK because it's bugged and crashes
         auto next = reinterpret_cast<const VkBaseOutStructure*>(info.pNext);
         while (next != nullptr) {
            switch (next->sType) {
               case VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_HOST_IMAGE_COPY_FEATURES_EXT:
                  {
                     auto hostImageCopyFeatures = reinterpret_cast<const VkPhysicalDeviceHostImageCopyFeaturesEXT*>(next);
                     const_cast<VkPhysicalDeviceHostImageCopyFeaturesEXT*>(hostImageCopyFeatures)->hostImageCopy = false;
                  }
                  break;
               default:
                  break;
            }

            next = reinterpret_cast<VkBaseOutStructure*>(next->pNext);
         }
      }

      return true;
   }
};

Link to proposal (if applicable)

• N/A

Fixes Issue(s)

• N/A

Checklist

• I have created this PR based on the dev branch

• I have followed the coding conventions

• I have added unit tests that exercise this functionality (Reference:
  testing guidelines)

• I have verified that all unit tests pass with the proposed changes

• I have submitted a signed Contributor License Agreement (Reference:
  Contributor License Agreement instructions)

[jesschimein]

Filed as internal issue #USD-11686

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