Stereo uses a 64 mm IPD. Left/right frames alternate and shift along the camera side vector. Arrow keys accelerate the cube on the XZ plane and it glides to a stop when released. Click the scene to lock the mouse. Use WASD to move the camera with buttery position smoothing. Mouse look keeps rotation smoothing. The aurora knot is the centerpiece again, with the simpler primitives arranged around it as a rotating gallery. Left click to grab whatever object sits under the crosshair, including the light. While the left mouse button is held, the selected object center stays on the center view ray at a fixed distance from the camera, like a rigid stick aligned to the crosshair. Releasing the left mouse button drops it immediately. Arrow keys still move the main cube. Forward/back follows the full camera forward vector so you can move above and below the scene. The grid is transparent except for geometry-based line strips on the XZ plane at Y = -1. Press Z to invert SYNC polarity.