Proposed RFC Feature: Introduce DirectX Agility SDK about sig-graphics-audio HOT 4 OPEN

To get some eyes on this after the holidays, added @moudgils
@VickyAtAZ
VickyAtAZ
@antonmic
antonmic
@galibzon
galibzon

from sig-graphics-audio.

Overall I like this addition. Dx12 RHI was bottlenecked by Agility SDK when it came to experimentation with new DX api so this is a welcome addition. A few points below

1. Shouldn't D3D12SDKVersion and D3D12SDKPath be part of Dx12 RHI gem as oppose to Launcher_Game_Windows.cpp or Editor/main.cpp? This way you won't have to duplicate it in two places.
2. AgilitySDK can be provided as a 3rd party lib but that requires a lot of work to maintain. You will need to create a script within https://github.com/o3de/3p-package-source and then use that pull in the 3p package at runtime. I wonder if providing a way to download directly via NuGet is an option during Configure. Microsoft provides a way to do this via.
   NuGet.exe install Microsoft.Direct3D.D3D12 -Source <FolderWith.nupkg> -OutputDirectory <DestinationFolder>

Tagging @spham-amzn and @nick-l-o3de to comment on ease of using Nuget for Agility SDK.

from sig-graphics-audio.

Overall I like this addition. Dx12 RHI was bottlenecked by Agility SDK when it came to experimentation with new DX api so this is a welcome addition. A few points below

1. Shouldn't D3D12SDKVersion and D3D12SDKPath be part of Dx12 RHI gem as oppose to Launcher_Game_Windows.cpp or Editor/main.cpp? This way you won't have to duplicate it in two places.
2. AgilitySDK can be provided as a 3rd party lib but that requires a lot of work to maintain. You will need to create a script within https://github.com/o3de/3p-package-source and then use that pull in the 3p package at runtime. I wonder if providing a way to download directly via NuGet is an option during Configure. Microsoft provides a way to do this via.
   NuGet.exe install Microsoft.Direct3D.D3D12 -Source <FolderWith.nupkg> -OutputDirectory <DestinationFolder>

Tagging @spham-amzn and @nick-l-o3de to comment on ease of using Nuget for Agility SDK.

1. I've tried adding these in DX12_Windows.h but it doesn't work, I can try somewhere else in DX12 RHI again.
2. That's a good way, I didn't try it before, I can take a look, and any help of using NuGet in O3DE or cmake is appreciated

from sig-graphics-audio.

1. The proposed addition of the USE_D3D12_AGILITY_SDK should be placed in a windows-specific only cmake file, and since it affects multiple targets, perhaps the USE_D3D12_AGILITY_SDK and D3D12_AGILITY_SDK_DEPENDENCIES should be defined in PAL_Windows.cmake

2. Using #if defined(AZ_PLATFORM_WINDOWS) will cause a validation error since its not permitted to do platform-specific gating in general in the common files. The PAL idiom requires that platform specific content reside in their respective PAL specific file, so in the example for Code/Editor/main.cpp, that block should instead be moved somewhere in https://github.com/o3de/o3de/tree/development/Code/Editor/Platform/Windows. Probably a trait header file, and you can follow the pattern that AzCore uses with AzCore_Traits_Platform.h, or you can add a main_Windows.cpp instead.

3. I think if its the case that the Agility SDK DLLs are meant to be project local, and that games that are distributed with it will need it, then create a new 3rd Party package for it is the correct approach. The NuGet.exe steps suggested can actually be used in the 3rd party script to generate the library.
   However, using this approach will require this DLL to be redistributed with any packaged windows game. Normally, for release builds, they are built monolithically and minimally to reduce (or eliminate) and dynamic module loading, so if we want to follow this approach, there will need to be a way to statically link the agility SDK (if possible).
   If this is not possible, then the packaged game will need to separately install this redistributable, unless the Agility SDK license allows for a 3rd party distribution for games in this manner.

The repo for 3rd Party packages is here.

from sig-graphics-audio.