Dioptra: GLB 3D Model Viewer

A 3D model viewer for iPhone and iPad that takes measurement seriously. Open a file, turn it over, and tap two points on the surface to get a real distance. FORMATS • glTF — .glb and .gltf • USD — .usdz, .usdc, .usda and .usd • STL — 3D prints and CAD exports, read in millimetres and turned upright • PLY — scans and photogrammetry, with per-vertex colour • VRM • Interactive pages — an .html export keeps its own controls and runs as it was built MEASURE • Tap two points for a true distance • Take as many measurements as you need; they stay listed with the model • Switch between metric and imperial whenever you like • Set what one file unit means: metres, centimetres, millimetres, inches or feet INSPECT • Orbit, pan and zoom, or leave it turning on its own • Wireframe, to see how a mesh is built • Studio, light and dark backgrounds • Play embedded animations, one clip at a time • Model…