How Rive is used
• The whole HUD is a Rive file written as RML with a coding agent and built with the Rive CLI (verify, publish, push).
• One state machine with seven layers runs it: Mode, Prompt, Subtitles, Token, Memory, Act Complete and Ambient.
• A Game State view model with 15 data-bound properties is fed live by the three.js game: the current light, objective, counter, prompts, subtitles and a mode-switch trigger.
• "Echo Veil" is a full-screen WGSL shader drawn on GPU Canvas through a Luau node script. It reacts to the active light and ripples on every switch.
• Click listeners inside the file let you switch the three lights on the Rive page itself, no game needed.
• The HUD was then refined by hand in the Rive Editor: the mode pips, lettering and the timing of the switch animation.