[MC-3248] Getting damage reduces TNT knockback Created: 17/Nov/12  Updated: 04/Feb/24

Status: Reopened
Project: Minecraft: Java Edition
Component/s: None
Affects Version/s: Minecraft 1.4.4, Minecraft 1.4.7, Snapshot 13w05b, Minecraft 1.5.2, Minecraft 1.6.1, Minecraft 1.6.2, Minecraft 14w30c, Minecraft 14w32a, Minecraft 14w34c, Minecraft 1.9, Minecraft 1.10.2, Minecraft 1.11, Minecraft 1.12.2, Minecraft 18w20c, Minecraft 1.13.1, 1.16 Pre-release 2, 1.16 Pre-release 4, 1.16 Pre-release 5, 1.16 Pre-release 7, 1.16.4, 20w46a, 20w51a, 21w03a, 21w05b, 1.20.4, 24w05b
Fix Version/s: None

Type: Bug
Reporter: Conem Assignee: Unassigned
Resolution: Unresolved Votes: 38
Labels: None

Attachments: File TNT Cannon.rar    
Issue Links:
Duplicate
is duplicated by MC-28859 TNT is less powerful on easy, Normal,... Resolved
CHK:
Confirmation Status: Confirmed
Game Mode: Survival
Category:
Player
Mojang Priority: Low
Area: Platform

 Description   

The bug

Like how random falling damage seemed when it first debuted in 1.3, I'm not sure if this is a bug or a deliberate change to gameplay mechanics, so...

Player launchers are a popular Minecraft invention. Basically, they involve wiring a ring of TNT so it detonates around the player and propels him/her skyward. However, they only work properly in Creative or Peaceful mode. When you switch to Survival on Easy, Normal, or Hard mode, their launching power receives a seemingly arbitrary nerf. A Player Launcher charged with 32 TNT blocks can send you over 300 blocks high in Creative/Peaceful, but on any other difficulty, the height caps out at about 66 blocks for seemingly no reason.

Here's a brand new video showcasing the issue: http://youtu.be/XihAFVogAQ8

Code analysis

Code analysis by marcono1234 can be found in this comment.



 Comments   
Comment by Fabian Röling [ 09/Feb/21 ]

Those are not valid on the bug tracker. If you find bugs while playing with Optifine, always verify that they also occur in Vanilla.

Comment by gnamf jojo [ 09/Feb/21 ]

Can confirm in 1.16.5-Optifine_HD_U_G6

Comment by [Mod] Avoma [ 05/Feb/21 ]

Can confirm in 21w05b.

Comment by [Mod] Avoma [ 29/Jan/21 ]

Can confirm in 21w03a.

Comment by [Mod] Avoma [ 08/Jan/21 ]

Can confirm in 20w51a.

Comment by Conem [ 17/Jun/20 ]

Confirmed in 1.16-pre7.

Comment by Conem [ 12/Jun/20 ]

Confirmed in 1.16-pre5.

Comment by Conem [ 12/Jun/20 ]

Confirmed in 1.16-pre4.

Comment by Conem [ 07/Jun/20 ]

Confirmed in 1.16 Pre-release 2.

Comment by Kraif [ 29/Aug/18 ]

Confirmed for 1.13.1. Please, if you don't mind, I'd like to be the reporter of this issue, I'll update it accordingly.

Comment by bob [ 26/Nov/16 ]

Can confirm for 1.11

Comment by Fabian Röling [ 16/Jul/16 ]

I always tested it with resistance 5, because the title is misleading. Changed it now and can confirm it, too.

Comment by Peter B [ 29/Jun/16 ]

Unfortunately, i have just tested this in 1.10.2, and i still have the problem. I use a dispenser tnt launcher with 12 tnt's per blast. With survival difficulty >0, i gain ~60 blocks height, whilst survival difficulty 0 gives me around ~190 blocks of altitude.

The setup i use is as follows:
I am standing on a fence surrounded by 8 water blocks in a square. Facing these water blocks are 12 dispensers filled with tnt which will instantly activate when a button is pressed.

Edit:
I've just redone your (Fabian's, see comments) test (as i understood it), and for me it gives the following results:

Survival, difficulty 0:
86 blocks
Survival, difficulty >0
60 blocks
Creative, any difficulty
86 blocks

Fabian, can you respecify your test? It's a bit strange that we get different results while attempting the same experiment.

Again, i'm fairly certain this is a result of the damage calculation. The damage dealt to the player knocks the player and thus slows it down. I believe this should not happen since acceleration happens regardless of how pleasant this is for any entity, and therefore i suggest that all situations should result in the same (86 blocks) result.

Comment by Fabian Röling [ 29/Jun/16 ]

I just tested in 1.10.2: I made five command blocks summon an instantly exploding TNT exactly on me. Tested in Creative and Survival, each difficulty 0 and 1. All tests launched me about 60 blocks up. Is there something wrong with my setup or is this bug fixed?

Comment by Marcono1234 [ 18/Mar/16 ]

Please link to this comment in the description

The following is based on decompiled version of Minecraft 1.9 using MCP 9.24 beta. All method and class names are the names used in the decompiled version.

The reason why this happens is very likely because the damage the player takes counteracts the motion caused by the explosion. This is because a net.minecraft.network.play.server.SPacketEntityVelocity packet is sent and maybe due to the delay between sending and receiving the packet the motion is not correct, but that is only an assumption.

Comment by Jaap-Willem Mink [ 07/Mar/16 ]

I also found this bug in 1.9! Hope it can be fixed as soon as possible.

Comment by Peter B [ 03/Mar/16 ]

It's still a concern in 1.9, why does it show "resolved"?

Comment by Galaxy_2Alex [ 24/Oct/14 ]

Is this still a concern in the current Minecraft version 1.8.1 Prerelease 3 / Launcher version 1.5.3 or later? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Comment by Matthew Paul Stone [ 27/Jul/14 ]

It sure is! I made a new video about it too. https://www.youtube.com/watch?v=uyXdu7z1-E0

It may be more of an unintentional feature than a glitch. It probably has to do with how you take no damage from TNT in creative or peaceful, while in a normal survival situation, simultaneous blasts of TNT can end up canceling each other out a bit and give you less vertical thrust. It's still inconvenient though cause it means a machine like a player launcher functions differently in a creative testing world, so you can't properly gauge how well it will work if rebuilt in survival.

Comment by [Mod] Ezekiel (ezfe) [ 26/Jul/14 ]

Is this still a concern in the latest Minecraft version 14w30c? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Comment by Galaxy_2Alex [ 21/Jan/14 ]

Is this still a concern in the current Minecraft version 1.7.4 / Launcher version 1.3.8 or later? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Comment by Matthew Sumner [ 15/Aug/13 ]

Yes this is still a problem. And I have attached a world save file (TNT Cannon) from the current version (1.6.2) to prove it.

This was from my own issue report, but it describes how the players are being affected more clearly:

"When on Peaceful mode TNT has the capability of launching the player past sky limit. But on easy, normal, and hard modes TNT isn't able to do much; It can't even send players 50 blocks in one direction.
Regardless of survival and creative, this still happens in both game modes. I have attached the following a world compromised of a TNT cannon setup to prove this bug exists. I've tested TNT multiple times with this cannon and the results are the same no matter how the cannon is configured, even in survival and creative. Peaceful is more powerful than the other 3 modes."

And also I can support that no matter how much TNT, even three TNT will only launch you a short amount rather than peaceful mode.

Comment by Tails [ 15/Mar/13 ]

Is this still a concern in the current Minecraft version? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

Comment by Matthew Paul Stone [ 06/Feb/13 ]

Yep! This time I recorded a video about the issue as well. Just follow the new link in the description.

Comment by Tails [ 05/Feb/13 ]

Is this still a concern in the current Minecraft version? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.

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