Reduce motion

since 0.7.0 or earlier Widgets and the rest

Open the live demo · Read the source · View on GitHub

Somebody who is made ill by moving pictures has already turned Reduce Motion on, in the system settings, probably years ago. A game that ignores that and offers its own slider three menus deep asks them to solve the same problem again, in a menu they may have to get through a moving camera to reach.

Note. flutter3d_game's real Accommodations is not a dependency of this app. This page reimplements its nine lines, calling the same MediaQuery.maybeDisableAnimationsOf Flutter already exposes, so the numbers below answer to this device's actual setting.

Step 1: A default, never an override #

/// A default, never an override: a game reads this where the player has not
/// said otherwise, and a slider they moved themselves still wins.
final class _Accommodations {
  const _Accommodations({this.reduceMotion = false});

  factory _Accommodations.of(BuildContext context) => _Accommodations(
    reduceMotion: MediaQuery.maybeDisableAnimationsOf(context) ?? false,
  );

  final bool reduceMotion;

  /// Nought when the player has asked for less movement: a camera that
  /// shakes on every landing is exactly what the system setting is about.
  double get cameraMotion => reduceMotion ? 0.0 : 1.0;

  /// The same fallback for a full-screen flash, kept separate because a
  /// flash is a photosensitivity question and a moving camera is a
  /// vestibular one.
  double get screenFlash => reduceMotion ? 0.0 : 1.0;
}

Step 2: Read what the platform already says #

final accommodations = _Accommodations.of(buildContext);

Step 3: Compare the two states #

const off = _Accommodations();
const on = _Accommodations(reduceMotion: true);

With the system setting off, a camera's own motion defaults to full. With it on, the default is nought — a starting point a game's own slider can still move away from, since this is a fallback and not a lock.