API for non-player entities to use Tinker tools (primarily projectile weapons)

[lcy0x1]

Minecraft Version

1.20.1

Forge Version

47.1.3+

Mantle Version

1.11.36

Tinkers' Construct Version

3.9.1.19

Problem description

Currently, ModifiableBowItem and ModifiableCrossbowItem are both restricted to player use only, while the underlying logic actually allow non-player to trigger most of the mechanics.

The current vanilla stack trace for mobs using projectile weapon is quite obscure and inflexible:
RangedAttackMob::performRangedAttack

• ProjectileUtil::getMobArrow
  • ArrowItem::createArrow
  • AbstractArrow::setEnchantmentEffectsFromEntity
• BowItem::customArrow

Since TConstruct does not follow the vanilla logic for arrow entity creation, could there be an interface for mobs to use TConstruct bows and crossbows?

I have already implemented mob using TConstruct bows and crossbows, but in a way that copied and modified a large chunk of respective TConstruct code. It's not clean and could break in the future if TConstruct modified this part of the code. Is it possible to extract an API for this, so that I can keep minimal repetition of TConstruct code?

This is my implementation: https://github.com/Minecraft-LightLand/ModularGolems/tree/lcy0x1/1.20/src/main/java/dev/xkmc/modulargolems/compat/materials/tinker/behavior

Suggested solution

Here is something I would propose:

class ModifiableBowItem {void shootArrows(LivingEntity user, ItemStack bow, ProjectileStrategy strategy)}

interface ProjectileStrategy {void shootArrow(Projectile arrowEntity, float arrowVelocity, float arrowGravity, float angleInDegree, float inaccuracy);}

Where ProjectileStrategy is an interface that allows mobs to control the initial velocity of the arrow.

This implementation would be very similar to respective Bow / Crossbow code, where there could b a ProjectileStrategy for player. It's the easiest fix

Alternatives considered

The alternative would be to follow the vanilla logic, where the major logic and hook moves to customArrow, and call that part in item usage.

Additional context

No response

Searched for existing enhancement?

Used the search bar, Checked the FAQ, Checked the in game books

[KnightMiner]

What prevents you from just firing arrows using the on finished using method in the bow?

Overall I'm not against adding more flexibility, but I'd want it to be done without you needing to hardcode to my specific bow class. In addition, its very important that all modifiers work if you added such an interface; includes ones that handle arrow finding and alike.

If you want to make a PR with your proposal that would give me more to base my thoughts on.

[lcy0x1]

ModifiableBowItem:

    public void releaseUsing(ItemStack bow, Level level, LivingEntity living, int timeLeft) {
        ScopeModifier.stopScoping(living);
        if (living instanceof Player player) {

It checks for player inside releaseUsing, which makes entities cannot use this method

[lcy0x1]

Also, the usage needs to be different for hostile mobs and companion mobs, in the following criteria:

• Hostile mobs should have infinite arrow, while companions should not
• Hostile mobs generally have less damage and lower arrow speed (and probably accuracy) than companions

I can help to make a PR, but the problem is that how flexible this API should be? There will always be arguments that bows should just follow the vanilla pipeline, which would be a structural change for TConstruct (because of the different inheritance hierarchy). There are 2 options:

• Create an API for TConstruct only. Mobs who wants to use TConstruct needs to make specific integration code. (More flexible, cleaner, easier to use)
• Follow vanilla pipeline so that all mobs are automatically able to use TConstruct bows (better compatibility)

[KnightMiner]

All mobs using our bows is the ideal, but that can't happen without some Forge/NeoForge changes, so its not high on the priority list.

That is really the place to start looking if you want to plan this out; add an API to Neo and I'll use it when I get to that version, and you can use that API for your mobs.

[lcy0x1]

I just went through the 1.21.1 projectile weapon code and it's far more obscure than 1.20.1, no hope to get anything done without major refactoring of vanilla code.

I guess I have to settle with my current approach.

[KnightMiner]

You can still make a suggestion to improve our API even if we can't change the vanilla API. Just make your proposal with the assumption that any mob might be able to use the tool.

[lcy0x1]

I'm making an attempt to merge the shoot logic from ModifiableBowItem and ModifiableCrossbowItem. I found that they use different angle calculation:

From bow:

arrow.shootFromRotation(player, player.getXRot() + angle, player.getYRot(), 0, velocity, inaccuracy);

From crossbow:

Vector3f targetVector = player.getViewVector(1.0f).toVector3f().rotate((new Quaternionf()).setAngleAxis(angle * Math.PI / 180F, upVector.x, upVector.y, upVector.z));
projectile.shoot(targetVector.x(), targetVector.y(), targetVector.z(), velocity, inaccuracy);

I think they are the same. May I just use the one from bow to replace both?

[KnightMiner]

I am nearly certain they are not the same, largely in part to how the crossbow shoot logic can handle multishot with horizontal angles and the bow can't.

Likewise, the shoot logic is not the same for the two. Crossbows handle fireworks, and have different multishot logic.

[lcy0x1]

There is multishot logic in bow logic as well, but instead of horizontal crossbow multishot, bow use vertical multishot?

Currently I restructured bow logic in the following way:

• User information (For player with bow: speed = 3, inaccuracy = 1, no infinity, do weapon durability cost)
• Shoot logic supporting multishot (common code)
  • Arrow creation logic. Use inheritance to allow crossbow to support rocket and mark arrow as shot from crossbow
  • Arrow modifier logic. Same for bow and crossbow.
  • Firing logic. This part bow differs from crossbow.
  • Shooting sound. Use inheritance to allow bow and crossbow to customize.
  • Durability cost. Same for bow and crossbow
• Individual code for weapon data manipulation