Partial (when on)
Yes, 15 (when on)
A redstone lamp can be used to produce switchable light.
To place a redstone lamp, use a redstone lamp item while pointing at a surface facing the space the redstone lamp should occupy.
Redstone lamps are redstone mechanisms and can be activated by:
- An adjacent active power component, including above or below: for example, a redstone torch (except that a redstone torch will not activate a redstone lamp it is attached to), a block of redstone, a daylight sensor, etc.
- An adjacent powered block (for example, an opaque block with an active redstone torch under it), including above or below
- A powered redstone comparator or redstone repeater facing the redstone lamp
- Adjacent powered redstone dust configured to point at the redstone lamp (or on top of it) or directionless; a redstone lamp is not activated by adjacent powered redstone dust that is configured to point away from it.
A redstone lamp activates instantly, but takes 2 redstone ticks to turn off (4 game ticks, or 0.2 seconds barring lag).
An active redstone lamp produces block light 15. An inactive redstone lamp produces no light.
Although a redstone lamp acts like an opaque block in most ways (torches and levers can be attached to it, redstone dust can be placed on it, etc.), an active redstone lamp is "transparent" to sky light, reducing the sky light level by 1.
A redstone lamp uses its ID to specify its activation state:
|Name||ID Name||Block ID|
|Redstone Lamp (inactive)||
|Redstone Lamp (active)||
Every redstone lamp (active or inactive) has a block data value of 0. Redstone lamps have no block states.
|November 11, 2010||Notch claimed that "lamps" had actually stood for "Light A-givin' Material Portal Side... the yellow stone thing"|
|1.2.1||12w07a||Added redstone lamp.|
|1.2-pre||Darkened texture for inactive redstone lamp.|
|1.2.4||Added 2-tick delay to deactivation.|
|TU12||Added redstone lamps.|
- See also: Lantern
Issues relating to "Redstone Lamp" are maintained on the issue tracker. Report issues there.
Note that lamps are themselves solid blocks, and so power other lamps. This causes the cross-shaped patterns that you see.
A glowing roof is easy to do - just lay wire across the blocks, or line the top of the lamps with redstone blocks. Floors and walls are also do-able. For a floor, just use the "knight's move" shape underneath the floor with torches. For a wall, use wall-mounted torches that power blocks above them.