Light and shadow play a major role in Thief, of course. Garrett is a creature of the night who sneaks around under cover of darkness, and stepping into the light usually amounts to a quick death for him. Garrett's current state of well-being is denoted on-screen by a gemstone icon linked to his health meter; the stone shines when Garrett stands in the light and grows dim in shadow. With the PS4 version of the game, the controller's light bar doubles up to serve the same function. When Garrett is safely hidden in the dark, the bar glows with its usual muted tones. Step into the open, however, and the light bar comes alive, shining with pure white intensity.
It's a surprisingly effective feature. While the DS4's light bar doesn't usually emit enough light to be distracting, its white setting is intense enough that it cast shadows in the demo room. There's no need to pay attention to the screen icon, because the room becomes flooded with illumination when you step into torchlight. It's a nice metatextual touch, and it's more or less guaranteed to work because Thief demands to be played in a dark room. It's one of the few games whose gloomy color palette makes sense, and because you need to play it in a low-illumination environment, the DS4 light bar works nicely.