Automatically scales UI canvas based on distance from the user to maintain constant angular size.
Ensures the UI maintains a minimum 3-degree visual angle for eye gaze interaction.
Reference Distance: 1 meter (base scale applies at this distance) Base Scale: 0.00131 (ensures 40-unit UI elements appear as 3 degrees at 1m)
Example: If base scale is 0.00131:
At 0.5m: Canvas scales to 0.5× → UI appears same angular size
At 1.0m: Canvas scales to 1.0× (base scale)
At 2.0m: Canvas scales to 2.0× → UI appears same angular size
Editor Support: Works in edit mode using Scene view camera for real-time preview.