This if fairly easy to do, but the command required is very long.
The way you should do this, as other answers have already pointed out, is by putting CanPlaceOn
tags onto the item. There's no easy way to do this once the items are already in the player's inventory, so instead you should do it for the dropped item entities with /data
.
CanPlaceOn
is also fairly annoying in that you need to name every single block you want to be able to place the block onto. I used the block name table from the Minecraft wiki, and wrote a script to convert the names into the right format.
Overall, the command you need to run on a fast clock is:
/data merge @e[type=Item] {Item:{tag:{CanPlaceOn:["minecraft:air","minecraft:stone","minecraft:grass","minecraft:dirt","minecraft:cobblestone","minecraft:planks","minecraft:sapling","minecraft:bedrock","minecraft:flowing_water","minecraft:water","minecraft:flowing_lava","minecraft:lava","minecraft:sand","minecraft:gravel","minecraft:gold_ore","minecraft:iron_ore","minecraft:coal_ore","minecraft:log","minecraft:leaves","minecraft:sponge","minecraft:glass","minecraft:lapis_ore","minecraft:lapis_block","minecraft:dispenser","minecraft:sandstone","minecraft:noteblock","minecraft:golden_rail","minecraft:detector_rail","minecraft:sticky_piston","minecraft:web","minecraft:tallgrass","minecraft:deadbush","minecraft:piston","minecraft:piston_head","minecraft:wool","minecraft:piston_extension","minecraft:yellow_flower","minecraft:red_flower","minecraft:brown_mushroom","minecraft:red_mushroom","minecraft:gold_block","minecraft:iron_block","minecraft:double_stone_slab","minecraft:stone_slab","minecraft:brick_block","minecraft:tnt","minecraft:bookshelf","minecraft:mossy_cobblestone","minecraft:obsidian","minecraft:torch","minecraft:fire","minecraft:mob_spawner","minecraft:oak_stairs","minecraft:chest","minecraft:redstone_wire","minecraft:diamond_ore","minecraft:diamond_block","minecraft:crafting_table","minecraft:farmland","minecraft:furnace","minecraft:lit_furnace","minecraft:standing_sign","minecraft:ladder","minecraft:rail","minecraft:stone_stairs","minecraft:wall_sign","minecraft:lever","minecraft:stone_pressure_plate","minecraft:wooden_pressure_plate","minecraft:redstone_ore","minecraft:lit_redstone_ore","minecraft:unlit_redstone_torch","minecraft:redstone_torch","minecraft:stone_button","minecraft:snow_layer","minecraft:ice","minecraft:snow","minecraft:cactus","minecraft:clay","minecraft:jukebox","minecraft:fence","minecraft:pumpkin","minecraft:netherrack","minecraft:soul_sand","minecraft:glowstone","minecraft:portal","minecraft:lit_pumpkin","minecraft:unpowered_repeater","minecraft:powered_repeater","minecraft:stained_glass","minecraft:trapdoor","minecraft:monster_egg","minecraft:stonebrick","minecraft:brown_mushroom_block","minecraft:red_mushroom_block","minecraft:iron_bars","minecraft:glass_pane","minecraft:melon_block","minecraft:pumpkin_stem","minecraft:melon_stem","minecraft:vine","minecraft:fence_gate","minecraft:brick_stairs","minecraft:stone_brick_stairs","minecraft:mycelium","minecraft:waterlily","minecraft:nether_brick","minecraft:nether_brick_fence","minecraft:nether_brick_stairs","minecraft:enchanting_table","minecraft:end_portal","minecraft:end_portal_frame","minecraft:end_stone","minecraft:dragon_egg","minecraft:redstone_lamp","minecraft:lit_redstone_lamp","minecraft:double_wooden_slab","minecraft:wooden_slab","minecraft:cocoa","minecraft:sandstone_stairs","minecraft:emerald_ore","minecraft:ender_chest","minecraft:tripwire_hook","minecraft:tripwire","minecraft:emerald_block","minecraft:spruce_stairs","minecraft:birch_stairs","minecraft:jungle_stairs","minecraft:command_block","minecraft:beacon","minecraft:cobblestone_wall","minecraft:wooden_button","minecraft:anvil","minecraft:trapped_chest","minecraft:light_weighted_pressure_plate","minecraft:heavy_weighted_pressure_plate","minecraft:unpowered_comparator","minecraft:powered_comparator","minecraft:daylight_detector","minecraft:redstone_block","minecraft:quartz_ore","minecraft:hopper","minecraft:quartz_block","minecraft:quartz_stairs","minecraft:activator_rail","minecraft:dropper","minecraft:stained_hardened_clay","minecraft:stained_glass_pane","minecraft:log2","minecraft:log2","minecraft:acacia_stairs","minecraft:dark_oak_stairs","minecraft:slime","minecraft:barrier","minecraft:iron_trapdoor","minecraft:prismarine","minecraft:sea_lantern","minecraft:hay_block","minecraft:carpet","minecraft:hardened_clay","minecraft:coal_block","minecraft:packed_ice","minecraft:double_plant","minecraft:prismarine","minecraft:barrier","minecraft:red_sandstone","minecraft:sea_lantern","minecraft:iron_trapdoor"],HideFlags:16}}}
Best Answer
Haste 255 makes you mine slower, because the number wraps around into the negatives. Haste 127 makes you mine the fastest.
There is no item that gives you haste (and the
effect.digSpeed
attribute modifier apparently doesn't work at all), so you have to use commands to check for holding the item in the main hand. Commands for that are easily found online.