xeogl
A WebGL-based 3D engine for technical visualization
...It gives you tools to create interactive 3D worlds in your browser. Load models from formats like glTF or OBJ, or generate them programmatically. Navigate them with the camera and script them with Javascript, to build compelling 3D presentations. Load multiple models. Isolate/move/emphasize objects. Camera navigation controls. Camera animations (flyto, follow, path etc). Emphasis effects (wireframe, ghost, highlight, outline). Annotations. Cross-section views. Scene object hierarchies. Transform hierarchies. Bounding volumes. 3D picking, raycasting. ...