While the technical specifications of the PS5 and Xbox Series X consoles are gradually being revealed, Microsoft has posted a blog post dedicated to software developments to announce a new extension of its DirectX 12 API. is rewarded on this occasion with a new name: DirectX 12 Ultimate. It is true that the latter is undoubtedly more attractive than the technical name which remains DirectX12 level 12_2.
If today, DirectX brings together many libraries, aiming to manage the interactions between the different hardware components and our software systems (OS, games, applications), the new Ultimate version will especially focus on expanding one area in particular: 3D rendering. Thus, this version will notably strengthen existing components, such as DirectX Raytracing or Variable Rate Shading. DX12 Ultimate will also integrate new ones, which resulted from the work of the main manufacturers of the GPU, but which had not yet been addressed by the API of Microsoft. This is the case of the Mesh Shaders function, which had been launched by Nvidia as well as the Turing GPUs.
Moreover, and quite logically, AMD and Nvidia are of course positioned in the wake of Microsoft’s announcements, and recalled their full support for DX12 Ultimate: Nvidia thanks to its Turing GPUs, and AMD thanks to the products that will depend on its future RDNA2 architecture. We are talking about graphics card products, but also Xbox products, which will ship AMD SoCs.
An API to attract them all and in raytracing to link them
A little more in detail, DX12 Ultimate will first formalize the feedback expressed by the developers in the use of DXR version 1.0. For example, some tasks inherent in raytracing rendering can be addressed directly to the GPU, without requiring interactions with the CPU. This concerns, for example, preparatory work for rendering, such as culling operations, which can be carried out by raytracing, and which are used to eject from the rendering process elements which do not contribute to the creation of the final image. On another note, the Inline Raytracing function will define a simplified form of the ray tracing rendering process so that developers can extend its use in scenarios where this would be relevant.
Microsoft has also used developer experience to simplify or expand the Variable Rate Shading feature, which was integrated into DX12 a year ago. Recall that the latter allows to play on the fidelity of the colors of the pixels in order to release GPU resources for more essential operations, from a point of view of the visual quality.
Finally, two other functions, new within DX12, will make their appearance: Mesh Shaders and Sampler Feedback, both stemming from developments around Nvidia’s Turing architecture. Finally, the idea of DirectX 12 is always the same: take the best technologies from each industrial player and integrate them into a single API that can be used by all.
Obviously, Microsoft communicates this data in order to shed more light on the possibilities of its next home console, the Xbox Series X. As such, we can note that AMD has released a demonstration video focused on raytracing and on its RNDA2 architecture. This architecture remains to this day the last great unknown as to the performance that will be able to deploy our future home consoles.