Esplosione

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TNT exploding.

An explosion is a physical event, generally destructive, that can be caused by several different circumstances. It can destroy nearby blocks, propel and damage nearby players, entities, and their armor, and cause one or more fires. Explosions produce a "shockwave" particle effect.

Multiple close explosions may propel objects further, but have no cumulative effect on the destruction of a block. This is because explosions' damage to blocks is evaluated individually (per explosion), and blocks' blast resistance does not become "weakened" per explosion.

"Destroyed" blocks have only a 25% chance of dropping as collectible resources (and otherwise disappear), generally making explosions a poor resource gathering technique. Items that already exist as dropped collectible resources are not affected by explosions.

The propulsion effect of explosions is often used for TNT cannons.

Explosion Type Power Notes

Wither
(on creation)
7

Ender Crystal
6 May start fires

Charged Creeper
6

Bed
(in Nether or End)
5 Starts fires

TNT
4

Creeper
3

Ghast
fireball
1 Starts fires

Black Wither Skull
1

Blue Wither Skull
1 Treats blast radius blocks (except bedrock and end portal frames) as having a blast resistance of no more than 4.

Effect[modifica | modifica wikitesto]

Model of block destruction[modifica | modifica wikitesto]

1352 rays from the explosion center to points that uniformly distributed on the surface of a cube centered at the explosion with an edge length of 2. (However, this only defines their directions, not their length)
The roughly spherical pattern of blocks destroyed can be seen here.

An explosion can destroy nearby blocks. Its blast effect is evaluated independently on many explosion rays originating from the explosion center, as shown in the right figure.

  • Each ray has an initial blast force randomized in [0.7 × power, 1.3 × power].
  • The effect of the blast force is examined at checkpoints on the ray with step length of 0.3.
  • The blast force is absorbed (block resistance/5 + 0.3) × step length by the non-air block (no matter whether destroyed) at each checkpoint, and attenuated by step length × 0.75 between checkpoints, until completely absorbed or attenuated.
  • A block is considered destroyed if it can't completely absorb the blast force at any checkpoint in it (air blocks can be destroyed too).

From the above process, the following results can be deduced (where ⌊x⌋ is the floor function):

  • The blast radius in the air of an explosion (i.e. only attenuated, not absorbed by blocks) = ⌊1.3 × power/(step length × 0.75)⌋ × step length = 10.2 (charged creepers), 6.9 (TNT), 5.1 (creepers), 1.5 (fireballs). For example, a TNT explosion can destroy a torch 7 blocks away. But how many blocks an explosion can destroy is non-deterministic and also dependent on the specific location of the explosion.
  • The minimum block resistance required to absorb maximum blast force of an explosion happening in nearby air = ((1.3 × power − attenuation steps × step length × 0.75)/step length − 0.3) × 5. To not be destroyed, a block has to absorb all blast force at the first checkpoint in it.
    • The attenuation steps is subject to collision restrictions. For explosion in air, there is at least one attenuation step. TNT and creeper explosion are always 0.49 and 0.5 meter away from nearest block (2 att. steps), but fireball explosion can happen anywhere (1 att. step).
    • Thus, the block resistances are 121.00 (charged creepers), 77.67 (TNT), 56.00 (creepers), 16.42 (fireballs).
    • So water, lava (Note: Only the stationary block) obsidian, and bedrock are always indestructible, and fences and less blast-resistant blocks can be destroyed by fireballs. These are theoretical values, and in reality less resistant blocks are not always destroyed, and since Minecraft is supposed to be simple, there is no such mechanic.

Interaction with entities[modifica | modifica wikitesto]

An explosion has different effects on entities than blocks. Entities are damaged and propelled by an explosion if within its damage radius of 2 × power. Note that the "damage radius" is different from the blast radius of explosion effect on blocks.

  • For each entity within the radius, define impact = (1 − distance from the explosion/radius) × exposure.
  • Apply (impact2 + impact) × 8 × power + 1 point (half-heart, so we don't have to divide by 2 everywhere) of damage to the entity.
  • Propel the entity so that its velocity increases by impact in the direction from explosion to the entity.

From the above process, the following results can be deduced:

  • Entities will always get at least 1 point of damage if they are within the radius, regardless of their explosion exposure.
  • The maximum damage that entities can take (at the explosion center with 100% exposure) = (1 × 1 + 1) × 8 × power + 1 point of damage = 97 (charged creeper), 65 (TNT), 49 (creepers), 17 (fireballs). When entities are away or covered by blocks from the explosion center, they take less damage.
  • The maximum velocity gain that an entity can obtain from a TNT explosion is 1, at the explosion center with 100% exposure.
A primed TNT AABB has directionally asymmetrical sample points (1/2.96 spacing) because of rounding.

Calculation of explosion exposure[modifica | modifica wikitesto]

Explosion exposure is simply how much an entity is visible from the explosion center, and is approximated with the ratio of visible sample points on the entity. The approximation algorithm has sampling error that results in directional asymmetry of propulsion. For example, a typical TNT Cannon has maximum range in the west direction partly because the primed TNT has largest sampled exposure in that direction.

Causing fire[modifica | modifica wikitesto]

If the explosion has the ability, it randomly starts fires in 1/3 of all destroyed air blocks that are above opaque blocks.

Permanent lag[modifica | modifica wikitesto]

Permanent lag is essentially lag-fallout from an explosion, this consists of drops, liquid-physics, and increased render-complexity of the crater.

It is recommended that when making a large creative-mode explosion, one uses the command "/gamerule doTileDrops false" to stop drops from being generated by explosions.

Resistenza alle esplosioni[modifica | modifica wikitesto]

[edit values]

Block name Blast resistance

Roccia di fondo
18,000,000

Blocco comandi
18,000,000

Portale dell'End
18,000,000

Portale dell'End (blocco)
18,000,000

Incudine
6,000

Tavolo per incantesimi
6,000

Ossidiana
6,000

Ender Chest
3,000

Flusso di lava
500

Flusso d'acqua
500

Lava
500

Acqua
500

Uovo di drago
45

Pietra dell'End
45

Blocco di diamante
30

Blocco di smeraldo
30

Blocco d'oro
30

Blocco di ferro
30

Blocco di redstone
30

Mattoni
30

Scalini di mattoni
30

Terracotta
21

Pietrisco
30

Scalini di pietrisco
30

Muretto di pietrisco
30

Sbarre di ferro
30

Jukebox
30

Pietrisco muschioso
30

Mattoni del Nether
30

Staccionata di mattoni del Nether
30

Scalini di mattoni del Nether
30

Pietra
30

Mattoni di pietra
30

Scalini di mattoni di pietra
30

Lastra di pietra
30

Porta di ferro
25

Generatore
25

Ragnatela
20

Distributore
17.5

Gettatore
17.5

Fornace
17.5

Faro
15

Carbone grezzo
15

Cacao
15

Diamante grezzo
15

Smeraldo grezzo
15

Staccionata
15

Cancelletto
15

Oro grezzo
15
Block name Blast resistance

Tramoggia
24

Ferro grezzo
15

Blocco di lapislazzuli
15

Lapislazzuli grezzo
15

Quarzo del Nether grezzo
15

Redstone grezza
15

Botola
15

Assi
15

Porta di legno
15

Lastra di legno
15

Scalini di legno
15

Baule
12.5

Banco da lavoro
12.5

Baule trappola
12.5

Calderone
10

Tronco
10

Libreria
7.5

Lanterna di zucca
5

Anguria
5

Testa di creatura
5

Zucca
5

Cartello
5

Blocco di quarzo
4

Scalini di quarzo
4

Blocco sonoro
4

Arenaria
4

Scalini di arenaria
4

Lana
4

Monster Egg
3.75

Binario attivatore
3.5

Binario rilevatore
3.5

Binario alimentato
3.5

Binario
3.5

Argilla
?

Terra zappata
3

Blocco d'erba
3

Ghiaia
3

Spugna
3

Supporto per armatura
2.5

Pulsante
2.5

Torta
2.5

Terra
2.5

Ghiaccio
2.5

Leva
2.5

Micelio
2.5

Pistone
2.5

Piston Extension
2.5

Pedana a pressione
2.5
Block name Blast resistance

Sabbia
2.5

Sabbia delle anime
2.5

Pistone appiccicoso
2.5

Pedana a pressione ponderata
2.5

Cactus
2

Scala a pioli
2

Netherrack
2

Vetro
1.5

Pannello di vetro
1.5

Luminite
1.5

Lampada a redstone
1.5

Letto
1

Sensore di luce diurna
1

Fungo gigante
1

Foglie
1

Neve
1

Rampicante
1

Neve (strato)
0.5

Aria
0

Carota
0

Arbusto secco
0

Fuoco
0

Vaso da fiori
0

Fiori
0

Erba
0

Ninfea
0

Baule trappola
0

Melon Stem
0

Fungo
0

Portale del Nether
0

Verruca del Nether
0

Pistone in movimento
0

Patata
0

Pumpkin Stem
0

Comparatore di redstone
0

Ripetitore di redstone
0

Torcia di redstone
0

Redstone
0

Arboscello
0

Grano
0

Canna da zucchero
0

TNT
0

Torcia
0

Cordicella
0

Gancio per filo da inciampo
0

Typical damage radius[modifica | modifica wikitesto]

The player will receive damage, if within these radii of a 100% exposure ground 1-, 2-, or 4-TNT explosion, with the amount of damage labeled on each circle in the figures below.

KillRadiiGrenade1.png KillRadiiGrenade2.png KillRadiiGrenade4.png

History[modifica | modifica wikitesto]

st
0.24Creepers were first introduced in on August 24, 2009, based on a failed pig model Notch had created.
0.26 (October 24, 2009)TNT was added.
Alpha
1.2Added Ghasts, which shoot explosive ghast fireballs.
Beta
1.5Creepers become charged when struck by lightning, increasing the explosion's radius and strength.
1.6Trying to sleep in the Nether causes the bed to explode.
1.8Explosions will now emit shockwave particles after exploding. Prior to Beta 1.8, explosions only emitted smoke.
1.9pre3Bed and ghast explosions cause fire.
1.9pre4Trying to sleep in the End causes the bed to explode.
Enchantment "Blast Protection" added, protecting against explosions.
1.9pre6Ender Crystal added, an entity which sits atop of a block of bedrock. It can be destroyed with a melee or hit with an arrow or snowball, causing an explosion.
Sound UpdateThe 'Sound Update' of November 13th 2011 gave TNT a new explosion sound.
Rilascio ufficiale
1.3.112w24aFixed explosions not pushing back players.
1.3.1Explosions damage the player different amounts on different difficulties, and no damage is dealt to the player on peaceful.
1.4.212w34aAdded the Wither, which shoots black wither skulls.
12w37aWither will make a massive explosion upon its creation after its health is fully charged.
Blue wither skulls added.
12w38bNew Creeper fall mechanics; Creepers will explode if they fall on the player from a certain height.
1.5Destroyed blocks have a 1/power chance of dropping as items; previously it was a fixed 30% chance.

Trivia[modifica | modifica wikitesto]

  • Explosions more powerful than 100 look mostly the same from the outside, as only certain lines are used to determine if a block breaks. However, some of those lines continue underground.
  • An explosion powerful enough to break bedrock would have a blast radius of over 30,000,000 blocks. If it were an uninterrupted blast, it would cover 238,775,501.2 blocks. However, explosions only follow certain lines, not every block (see previous).
  • Any explosion going off in flowing water will apply propulsion to entities, but it will not affect any block, whether the blast resistance of that block is low or high.
  • Explosions in or under water won't emit particles.
  • Explosions can redirect projectiles including Ender Pearls.
  • Explosions can break blocks on the other side of blast-resistant blocks that survive.
  • Explosions will propel dead mobs' bodies if they go off just after the mobs dies.
  • If primed TNT explodes in a large, solid cube of stone blocks, it will create an exact 3x3x3 cube inside.

References[modifica | modifica wikitesto]