Microsoft has just released its latest DirectX Agility SDK. Though it comes packed with several ground-breaking ray tracing improvements, the biggest attractions are Shader Execution Reordering (SER) and Opacity Micromaps (OMM). Let us explore what these mean for your future gaming experience.
Ray tracing, which gives a very realistic light, shadow and reflection look to games, can be quite taxing on your graphics card. The new upgrades from Microsoft, however, aim to create more efficiency in the process.
Picture your GPU trying to deal with a million tiny light rays all at once. SER tells the GPU how to organize these tasks in a more intelligent way. By reordering the way in which GPU threads (think of them as tiny workers) approach these light rays, SER cuts down on chaos and enables seamless collaboration. The result? Performance boosts of up to an average of 2 times over pre-existing implementations, on path tracing-heavy games that support SER-from an already crazy performance leap!
Ever wondered how things such as fences, leaves on trees, or puffs of smoke appear in games? These often resort to using "alpha-tested geometry," which becomes a ray-tracing nightmare because then the GPU must figure out whether a light ray has passed through a transparent wedge or intersected with something solid. OMM allows the hardware to intelligently process these transparent and semi-transparent objects. It allows the GPU to quickly determine opacity during ray tracing, thus either skipping or relaxing areas requiring the maximum amount of calculations. In return, the efficiency gain for actual rendering would be better than what is visually perceptively sacrificed. For path tracers, OMMs may boost performance by 2.3 times
While SER and OMM are great headline makers, other important updates come with the latest Agility SDK:
- Cooperative Vectors: This opens up new hardware acceleration for complex math operations, thus allowing developers to mix rendering techniques driven by artificial intelligence into real-time graphics to offer better performance.
- Direct3D Video Encoding Updates: Updates for video encoding work better complex reference frame scenarios and allow for two-pass encoding with a lower resolution for the first pass.
- D3D12 Tiled Resource Tier 4: This overturns age-old constraints for developers, all in the name of better texture streaming and, in turn, greater flexibility in managing game textures. Driver support for this is rolling out from AMD, Intel, and NVIDIA.
Impressive demos have already been put on display by Microsoft and its partners. For example, OMM was able to demonstrate that NVIDIA could increase frame rates in one scene from 55 to 90 FPS, which was a greater than 60% improvement!
Assuming game projection paths such as Alan Wake, visual fidelity requires heavy utilization of alpha-tested geometry and path tracing. Without these new optimizations, an RTX 4090 might require about 16.8 ms to render the complex scene. Now, with both SER and OMM, the same scene has the potential to render in just 10.2 ms. That's quite significant, and it leads straight to smooth gameplay.
All good news from these DirectX advancements. As game developers begin to integrate SER and OMM into their new titles, we can expect more beautifully ray-traced worlds running more easily on modern GPUs. Open all potentials on today's fantastic graphical hardware.
