The Emperor Has No Presence — or Rigid Body: Why AR Feels Broken, and What We Can Do About It

Raycasting is one of the most important concepts in AR. This talk will explain what it is, how it works, and why it’s essential — in a way anyone can understand.

Augmented reality still struggles with presence. A virtual chair hover above the floor instead of resting on it. A character might walk straight through a wall. A digital human might ignore the user's gaze. These aren’t just glitches — they’re signs of missing spatial logic.

This talk focuses on practical solutions using raycasting.

Through demonstration, we’ll show how raycasting enables core features like collision detection, surface awareness, gaze interaction, environmental feedback, and basic pathfinding. These mechanics are foundational to building believable, responsive AR.