Overview
Open-source O3DE and most engines default to single-precision floats. Precision falls with distance from the origin: at 100 km, centimeter-scale error shows up as jitter, interpenetration, and unstable physics — a hard blocker for city-scale twins, flight simulation, and real geographic scales.
DawnEngine completed an engine-wide double-precision large-world upgrade: full double precision on the CPU; on the GPU, render-origin relative coordinates keep the GPU on single precision so render performance is not dragged down. Measured at 100 km from the origin, vertex accuracy stays sub-millimeter.
Key Capabilities
- End-to-end double precision: transforms, bounds, frustum culling, physics, vegetation, and editor placement.
- Render-origin relative: GPU stays single-precision; frame rate unaffected.
- Quality gates: 150+ precision tests in CI to prevent regressions.
- One large-world contract: shared with World Streaming and PolyTerrain.
Use Cases
- City / campus-scale digital twins and visualization.
- Aerospace, unmanned systems, and large-scale simulation.
- Projects that need real geographic scale (see Cesium 3D Tiles).
Related Features
Double precision is the cornerstone of large worlds, typically paired with World Streaming and PolyTerrain for seamless, accurate large-scale worlds.