Post
Visual cues that scream 'you can interact with this' without needing a tooltip.
Borrowed from UX design pioneer Don Norman, affordances in games are visual properties that communicate interactability. A ledge with a slightly different color? Climbable. A cracked wall? Breakable. A glowing object? Pickupable. Good affordances make a game world readable at a glance. Bad affordances force players to mash the interact button on every surface or, worse, walk past critical paths because nothing signaled 'go here.' The trick is making affordances clear enough to register subconsciously without looking like a checklist of highlighted objects.
Example
Uncharted's climbable ledges are always slightly yellow or white, creating a visual language players absorb without thinking about it. Breath of the Wild goes even further -- anything that looks climbable IS climbable. Mirror's Edge pioneered 'Runner Vision,' painting climbable objects red so players could read the environment at full sprint speed.
Why it matters
Affordances are the bridge between a developer's intention and a player's understanding. Without them, players get lost and frustrated. With too many, the world feels like a theme park with arrows painted everywhere. Striking the balance is a core UX skill that separates polished games from confusing ones.
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