Monospace Design TUI Standard / Reference Surface
§10 Motion & Feedback
§10.1 Timing Tiers
Applications MUST categorize all visual transitions into these 4 tiers:
| Tier | Duration | Use |
|---|---|---|
| Instant | 0ms | State toggles, key echo, character insertion |
| Fast | 50–100ms | Button press feedback, cursor movement animations |
| Standard | 150–300ms | Panel transitions, menu open/close, tab switch |
| Slow | 300–500ms | Screen transitions, progressive disclosure reveal |
Durations exceeding 500ms MUST NOT be used for UI transitions. (M3 §3 motion tokens, monospace-design-tui-research.md cross-cutting synthesis)
§10.2 Long-Running Operation Feedback
Any operation taking longer than 100ms MUST display immediate feedback:
- Operations <2s: spinner or progress indicator.
- Operations 2–10s: progress bar with percentage or step count.
- Operations >10s: progress bar with estimated time remaining.
Applications MUST NOT leave the terminal without visual feedback during any operation. A “hanging” terminal with no indication of progress is a violation. (tui-architect state transparency rule)
§10.3 Terminal Capability Degradation
Applications MUST degrade motion gracefully based on terminal capabilities:
- Dumb terminals (
TERM=dumb): All transitions MUST be Instant (0ms swap). - Standard terminals: Full timing tiers apply.
- When
NO_MOTION=1orREDUCE_MOTION=1environment variable is set: All transitions MUST be Instant.
(Apple HIG §4 reduced motion, Terminal §6)