Core principle

Human Adaptive Interaction

LIM no longer designs only for screen size. It designs for the human, the device, the input method, and the surrounding context.

Interactive Human Adaptive demos (attention zone, haptics, sensors) live in lab/human-adaptive/. This Runtime chapter documents principles only.

Design for humans

Responsive Design adapts to the screen. Adaptive Design adapts to the device. Layered Interface Method adapts to the human.

Not the user adapting to the interface. The interface adapting to the human.

Behavioral Equivalence

The same user intention must be realized through different behaviors depending on input. Do not copy desktop onto mobile. Do not copy hover onto touch. Each device receives a natural interaction model.

Desktop

Hover
Preview
Click
Action

Touch

Attention Zone
Preview
Tap
Action
Long Press
Context

Keyboard

Focus
Preview
Enter
Action

Pen

Hover
Preview
Tap
Action

Human Reach Model

The interface adapts not to the screen — it adapts to human reach. Critical actions move toward natural interaction zones (thumb comfort research).

Desktop

Tablet

Phone · left hand

Phone · right hand

Primary CTAs, navigation, and high-frequency controls belong in easy reach. Rare or destructive actions may sit farther away — never the reverse.

Attention Zone Activation

On touch, the hover analogue is the Attention Zone — the screen region where interaction is most probable. When a card enters that zone it may play a preview. Navigation does not fire until tap.

Lifecycle: hidden → visible → attention → engaged → activated. Only one element holds is-attention at a time.

Card 01

Scroll me into the zone

Preview activates in attention — tap engages. No accidental navigation.

Card 02

One attention at a time

Neighbors stay calm while this card holds focus of the zone.

Card 03

Keyboard works too

Focus maps to engaged — Enter maps to activated.

Card 04

Built on IntersectionObserver

LIM owns selection scoring so the zone stays intentional.

Input Native Design

Not Mouse First. Not Touch First. Input Native. Every component must document behavior for Mouse, Touch, Keyboard, Pen — and leave room for Gamepad and Voice later.

Component contract

Ship the matrix with the component. If a modality is unsupported, say so — do not fake hover on touch.

Sensor Driven UX

Sensors may inform spatial understanding — never decoration for its own sake. Progressive enhancement only: LIM remains correct without gyroscope, vibration, or ambient light.

  • Device Orientation — subtle parallax (hero layers ≤ a few pixels)
  • Gyroscope / Accelerometer — optional depth cues
  • Ambient Light — when available, soft theme hints
  • Time of Day — day/night atmosphere alignment
  • Reduced Motion — all sensor motion respects preference

Reading environment…

Environmental Awareness

LIM understands the surroundings as well as the user: light theme ↔ morning, dark theme ↔ night, orientation changes composition, landscape carries more information, portrait carries more air.

LIM Haptics

Tactile feedback confirms state change — it does not decorate. Components never call navigator.vibrate directly. They call semantic tokens through LIM.haptics.trigger().

LIM.haptics.trigger("selection");
// tokens: tick · selection · confirm · warning · error · boundary

Haptic principles

  • Haptics follow state
  • One event — one signal
  • Intensity follows consequence
  • Never haptics alone
  • User control (and reduced motion)
  • Rate limiting

Apply thoughtfully on picker, slider, switch, tabs, drag, and modal boundaries.

Multisensory feedback

Every interaction is a stack: Visual → Motion → Haptic → State. Example switch: knob moves → color shifts → short tactile tick → new state is true.

Mobile exclusive interactions

Do not port desktop habits onto touch. Use what touch does well — and document where not to.

Long Press

Context menus, peeks — never the only path.

Double Tap

Zoom / favorite when discoverable.

Press + Drag

Reorder, scrub values.

Swipe

Navigate peers, dismiss — with visible alternatives.

Snap / Momentum

Lists and carousels that feel physical.

Rubber Band

Use sparingly — never hide critical actions behind stretch.

Discoverability

Gestures are never the only way. Every gesture needs a visually discoverable alternative. Long press accelerates — it does not replace the button.

Gamepad analogy

Modern controllers are designed around human anatomy. LIM applies the same idea to digital products: hand placement, natural zones, holding context, and how the device is gripped.

Design manifesto

Responsive Designadapts to the screen.
Adaptive Designadapts to the device.
Layered Interface Methodadapts to the human.

Design for Humans.
Not for Viewports.