Java Edition 12w40a

12w40a is the tenth snapshot released for Java Edition 1.4.2.

World generation

 * Swamp huts
 * New generated structure.
 * Located in swamp biomes.
 * Spawns witches.

General

 * NBT tags
 * Custom items can now be named using NBT tags (intended for custom map makers).
 * Using the NBT, it is possible to add custom to items, as well as a  list for that item.


 * Superflat
 * Added superflat preset "Redstone Ready" with 52 layers of sandstone, 3 layers of stone and 1 layer of bedrock.

Blocks

 * Beacons
 * Texture has been altered.
 * Beam texture has also been changed.


 * Fire
 * Spreading has been nerfed to prevent infinitely spreading fires.

Items

 * Eye of ender
 * Can now be used in superflat worlds, if the stronghold generation is enabled.

Mobs

 * Slimes
 * Now spawns in Swamp biomes at low light level.

Gameplay

 * Inventory
 * Better management.
 * The pick block action now works on blocks that are represented as items in the inventory (E.g.: repeater, redstone dust, and tripwire).
 * Pressing the 1-9 hotkeys while hovering over an item will put that item into the corresponding hotbar slot.
 * If there is already an item in the assigned hotbar slot, the hotbar item and the selected item swap position.
 * When in creative inventory, a full stack of that item will be transferred to that hotbar slot.
 * In creative mode, players can now shift-click items between the hotbar and the survival inventory.
 * The left-click action will no longer open doors, pull levers, push buttons or open trapdoors.
 * When in creative mode, on an item will pick up a stack of that item.

General

 * Superflat
 * Flatworld configuration now allows the player to generate trees, strongholds etc.
 * Now pumpkins, tall grass, flowers, trees, mineshafts, dungeons, strongholds, lakes, desert wells, ravines and ores will spawn on superflat maps.

Fixes

 * 13 bugs fixed
 * Fixed the wither's starting explosion not being disabled by the mobGriefing gamerule
 * Fixed a few crash bugs related to world generation, map item expansion, and other things.
 * Reverted previous lighting changes, which corrected such bugs as:
 * The Nether being extremely CPU intensive.
 * Map generation taking extremely long.
 * Fixed mob AI considering cobblestone walls as blocks of normal height.
 * Fixed a few texture oddities with the witch.
 * Fixed entities in water producing glitchy water sound.
 * Gaining multiple levels at a time will no longer play the leveling up sound over itself as many times as leveled.
 * Fixed the "A 64 bit Java installation is recommended for 'Far' render distance (you have 32 bit)" message being covered by the bottom 2 buttons.
 * Fixed pets teleporting around randomly.
 * Fixed being unable to place paintings larger than 1x2 and them popping off if they have been placed before.
 * Fixed destroying blocks under the player with efficiency-enchanted gear.
 * Fixed potion spawners crashing the game.