Nvidia's new ray-tracing sample handles a 1.6-billion-triangle scene with just 2GB of VRAM dedicated to geometry.
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When a scene goes over budget, it settles at lower detail instead of constantly swapping geometry in and out of VRAM. By default, this is based on 2GB of VRAM for streamed geometry, another 2GB for ray-tracing acceleration structures, and 4GB of material textures, but these are adjustable. The existing tessellation path remains.
In the case of Nvidia’s sample Zorah, there are 1.6 billion unique triangles in a 70GB download, with a first load that can require up to 64GB of RAM at peak. Zorah uses 31GB of mesh data, but the courtyard sample view only has 1.5GB of mesh data in VRAM, using an RTX 5090 at 4K with DLSS Quality.
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An existing problem, Nvidia said in August, is that under ray tracing, Nanite elements “switch to a single, static low-detail mesh” because it’s “prohibitively expensive” to build acceleration structures for them with “existing DXR 1.2 and Vulkan APIs.” It has taken six years of research and development to pioneer the new technology, with the innovations debuting with Gears of War: E-Day on Oct. 6. These will later be part of Microsoft’s
DirectX Raytracing 2.0 standard, according to Nvidia.
