Feature Request : Knockback

[C1ffisme]

Currently, there is no form of knockback. If you hit something/someone, he/she/it just get damaged, but not pushed back. Now, I could implement this and put it in the code for swords, but what would be the point? You would have to tell all the modders to code their weapons to be like the default swords.

Now, if we want a weapon or object that dosen't use knockback (e.g, __builtin:item) then we add a group to it like knockback = false. That way modders can chose to use knockback or not depending on what they are making. Also, I would optionally like an option called knockback_distance that tells how far you would fire the hit object.

If we add this, it might lead to more interesting mods. I can already see a soccer mod where you have to hit the ball with your hand and use knockback to push it along.

Now, suppose some griefers use knockback for griefing, by pushing people into lava, well, we can add a config option to disable knockback, in minetest.conf. Maybe something like do_knockback = true?

Anyway, I want to see what the community thinks of adding this.

[paramat]

Sounds fun, TNT could knockback players too depending on their distance.

[C1ffisme]

Yes. Maybe a ObjectType.knockback(knockback_distance) function for, well, objects (Luaentities and Players).

[ghost]

You have my vote!

[nerzhul]

agree, but need a protocol bump to implement to action

[Wuzzy2]

Knockback is a great idea, it would greatly enhance gameplay.

The idea as such needs to be more clearly specified.

First, it is unclear how knockback strength should be specified. Punches should vary from no knockback over weak knockback to strong knockbacks, but where do you specify it?

One possibility is to give items/tools/weapons a base knockback strength, so if you punch an object with this item, this knockback strength is applied to the object.
So you could have items causing a lot of knockback, just a little or none at all.

Also, knockback should also apply for entities.

Also, I would suggest that knockback resistance is not specified on a yes/no basis but on a scalar basis. Every object should have a non-negative knockback factor, so the actual knockback is * . This is usual to make targets either more prone to knockbacks or more resistant, or even immune to knockbacks (knockback factor 0). The default knockback factor should be 1.

Lastly, all functions in the Lua API dealing with punches etc. should be extended with a knockback parameter. I.e. if you want to punch something with Lua, you can set the knockback strength of the punch.

nerzhul: Then its good that 0.5.0 is in the making, compability is allowed to be broken. :=)

[ghost]

In mobs redo they use hitters tool capabilities as a multiplier to determine the strength of the knockback. I thought that was pretty clever.

[C1ffisme]

@Wuzzy2 Basically, yes. I want that. Like I said, there should be a setting whether knockback applies to certain objects, like how there is a setting that gives objects HP. on_punch and such should be updated, but how about with a parameter that enables/disables knockback and one that defines how far the object is shot. Maybe even negative arguments to the latter one could be used to make a tractor beam or mob that is really rather hard to get rid of.

[paramat]

For some (not all) situations this could possibly be done in lua by setting player's velocity. The TNT mod could give players a little kick even when far away to simulate a shockwave: knockback being exponential with distance.

[C1ffisme]

@paramat It could be done by just adding code, but I wanted to make it available for modders without having old mods have no knockback, and making swords have extra code.

[paramat]

Yes certainly i approve. I might try editing the lua TNT mod for a shockwave kick.

[ShadowNinja]

It doesn't have that feature because it isn't currently possible. You can't set player velocity or acceleration.

[Wuzzy2]

Here is the issue for missing setvelocity for players: #1176

[paramat]

Issue #1176 shows that players do not actually have velocity.

[KarlHegbloom]

The parachute mod is worth looking at with regards to this. An object can be attached to the player and it's velocity and acceleration set, I think. The player stays attached to the object.

[wilkgr76]

As for swords, perhaps add a way to hit players/entities with the flat of your sword, so that you knock them back further.

[Fixer-007]

I would like to see this too!

[C1ffisme]

Would it be worthwhile to rewrite Object:punch() to apply knockback based on where the hitter is?

[KarlHegbloom]

Sure. What about TNT cannons that can throw the player or objects?

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On Mon, Mar 13, 2017 at 10:02 AM C1ffisme ***@***.***> wrote: Would it be worthwhile to rewrite Object:punch() to apply knockback based on where the hitter is? — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#2394 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AACslgOtMKtblLIXF7xumDe5jGafr-GKks5rlWixgaJpZM4DmnXl> .

[raymoo]

I guess this feature can't be dismissed anymore now that we have CSM.

[sofar]

The player is still not a modifyable entity/object in CSM

[raymoo]

I mean that nobody can say "Let's wait for client side scripting before implementing this"

[Fixer-007]

https://github.com/tenplus1/playerplus has knockback introduced by @tenplus1

[TS440S]

Is this still being worked on or at least in a todo list?