Holdouts still on Windows 7 have reason to feel a little smug in their stubbornness this week. Jianye Lu, Program Manager for Microsoft's Graphics Team, posted an update to the DirectX Developer blog announcing the expansion of an initiative which aided game developers in porting over the benefits of their DirectX 12 API to the now borderline obsolete (but still popular) OS. Benefits such as the DirectX Raytracing API extension.
In March it was revealed that Microsoft would effectively break the shackles of Windows 10 exclusivity for DirectX 12 by helping developers port useful aspects of the API into the game code directly. The 'close to metal' API is similar to Vulkan in that it helps developers get more out of graphics hardware, and in some instances DX12 has worked wonders to improve performance in games developed with it at its core. By contrast, retrofitting DirectX 12 to mature game engines has been less impactful, or in rare instances a retrograde step.
Microsoft announced that they worked with Blizzard Entertainment to develop a version of the World of Warcraft Client that incorporated a number of DirectX 12 features directly. Update 8.1.5 was the first revision rolling out these changes to the retail client, and it immediately had an positive impact on multi-core utilisation in both Windows 10 and 7 environments. Hence DirectX 12 in Windows 7... ish.
The initiative was a major lift for the WoW community as long-term MMO players tend to retain fairly static system configurations. Many go years on end without meaningful hardware or OS upgrades, quite unlike those who engage in the Triple-A gaming scene. So it was in effect a 'free' performance boost for them not long into the lifespan of WoW's most recent expansion.
At the time Microsoft left the door open to working with other developers, but the nature of porting these features means it's only possible on a per-game basis. The market is potentially huge: some 30% of gamers still run Windows 7 compared with just shy of 50% on Windows 10. However Microsoft maintained that DirectX 12 in Windows 10 would still be the best environment, and to a certain extent it was assumed that advanced features such as DirectX Raytracing would remain exclusive. Now though it appears that isn't the case.
Three new resources are included in the latest update for game developers working to bring DirectX 12 feature to Windows 7: the Developer Guidance Document; D3D12onWin7 NuGet package, which contains headers, binaries etc; and D3D12 sample code that runs on both Win7 and Win10. The first of these includes the following critical FAQ response:
Q: Do you support all D3D12 features on Windows 7?
A: The current runtime supports D3D12 features as released in Windows 10 October 2018 Update (notably, DX Raytracing but not DirectML) on Windows 7.
A: The current runtime supports D3D12 features as released in Windows 10 October 2018 Update (notably, DX Raytracing but not DirectML) on Windows 7.
And so, DXR features may soon be ported to games running on Windows 7 as well as Windows 10. This could also pave the way to bringing NVIDIA RTX Raytracing support to Windows 7 systems with compatible hardware and driver packages. But what's perhaps most promising is that developers, particularly the indies, will feel emboldened to leverage these new features in novel and unpredictable ways rather than let them remain the province of the major development houses.
SOURCE: DirectX Developer Blogs, PCGamesN.
