AMD Unveils Tetrahedral Cages Ray Tracing Method, Cutting VRAM Use 97.8%

AMD (NASDAQ: AMD) announced a ray tracing research technique called "Tetrahedral Cages" that reduces VRAM usage for large-scale scenes from 80GB to 1.7GB, a 97.8% cut, in tests on the Radeon RX 9070 XT. The method separates static and dynamic geometry, encapsulating dense models in simple cages so inner BVH structures stay static and reusable. In a test scene with 25,000 dynamic plants, BVH update time fell to 3.3 milliseconds from over 300 milliseconds, a 90-fold efficiency gain. The RX 9070 XT sustained above 60 FPS at 1080p with 500 million dynamic triangles. AMD Fellow Holger Gruen said the technique targets BVH overhead in ray tracing. It suits dense scenes such as grass, forests and crowds, but cannot handle animations requiring precise deformation or topology changes. The research won third prize at High-Performance Graphics 2026. AMD plans C++ libraries and DXR interface samples, with no timeline for game integration.