Accessibility in TETERI

Keyboard navigation, screen reader announcements, reduced motion, and the honest limits of a canvas game.

The playfield is a canvas, which assistive technology cannot read. That constrains what is achievable, and it is worth being straightforward about both the work done and the limits.

Keyboard

Every control on every screen takes keyboard focus and shows a visible ring when it has it. The ring appears on keyboard focus only, so it does not flash at mouse and touch users.

The game itself is fully playable from the keyboard, which was never in question, but the menus, settings and lobby are too.

Screen readers

The overlay screens are named modal dialogs rather than anonymous containers, so they announce themselves properly.

Because the board cannot be read, a live region announces the moments that matter: the run starting, along with a one-line summary of the controls; each level increase; and the final score at the end of a run. Online lobby status messages are announced as they change.

That is a genuine limitation rather than a solved problem. A blind player cannot play this game from those announcements, and pretending otherwise would be dishonest. What the announcements provide is orientation and outcomes.

Reduced motion

If your system asks for reduced motion, screen shake and scanlines default to off, and the particle effects and full-screen flashes are damped to about a quarter of their usual intensity. All of it stays adjustable.

Colour

The seven pieces use the conventional colours, which are distinguishable by brightness as well as hue, and every block is drawn with a light top edge and a darker base so shape reads independently of colour. Nothing in the game requires distinguishing red from green to play.

Motor

Auto-shift timings are set so that a single tap moves exactly one cell on every input method. Lock delay with move resets gives a generous window for adjustment. There is no time pressure in the menus.

What is missing

There is no colourblind palette option, no adjustable text size beyond your browser's zoom, and no way to slow the gravity curve. Those are real gaps.

Read next

• Why Play TETERIFree, instant, offline-capable, and it asks nothing of you before you can start. A straight account of what it offers.
• The Four Game ModesMarathon, versus CPU, split-screen and online duels, and what each is actually for.
• Every Control in TETERIThe complete list for keyboard, touch and gamepad, including the ones that are not obvious.
• Playing on a PhoneTwo layouts, two control schemes, and the specific problems that had to be solved to make touch work properly.
• Where the Name "Tetris" Comes FromA Greek numeral prefix welded to the name of a racquet sport, because the author liked both.
• The Arcade Versions and What They ChangedA coin-op cabinet has different incentives to a home console, and the design shifted to match.