How to draw particles from BlockPos A to BlockPos B

[SirEnder125]

Hello! I want to make an item that draws particles to nearby, living entities every inventory tick. This is the code that I have tried:

public class OreFinderItem extends Item {

    public OreFinderItem(Settings settings) {
        super(settings);
    }

    @Override
    public void inventoryTick(ItemStack stack, World world, Entity entity, int slot, boolean selected) {
        if (stack.getItem() == ModItems.ORE_FINDER && entity instanceof PlayerEntity)
        {
            drawParticles(world, (PlayerEntity) entity);
        }

        super.inventoryTick(stack, world, entity, slot, selected);
    }

    public void drawParticles(World world, PlayerEntity user) {
        if (world.isClient)
        {
            BlockPos playerPos = user.getBlockPos();
            int x = playerPos.getX();
            int y = playerPos.getY();
            int z = playerPos.getZ();

            List<LivingEntity> livingEntities = world.getEntitiesByClass(LivingEntity.class,
                    new Box(x - 10, y - 10, z - 10, x + 10, y + 10, z + 10),
                    EntityPredicates.VALID_ENTITY);

            for (LivingEntity entity : livingEntities)
            {
                if (entity != user)
                {
                    Vec3d entityVector = new Vec3d(entity.getX(), entity.getY(), entity.getZ());
                    Vec3d playerVector = new Vec3d(x, y, z);

                    Vec3d velocity = entityVector.subtract(playerVector);

                    world.addParticle(ParticleTypes.CLOUD,
                            x, y, z,
                            velocity.x, velocity.y, velocity.z);
                }
            }
        }
    }
}

drawParticles() is called as expected, and does draw particles from the player to the entity. The problem is that the particles go directly through the entity, and go past it indefinitely...
How can I get it so that it stops at the entity's position, in other words, point B?

[warjort]

The cloud particle effect hardwires its Particle.collidesWithWorld to false in its constructor.
But even then, I believe setting it to true just checks block collisions and the world border, not entity collision.

To get entity collisions you are going to have to write your own Particle (e.g. copy CloudParticle) then override the Particle.move() method to also check entity collision.
Again, you have to do this yourself, normaly entity collision requires an entity to check against other entities, e.g. see ProjectileUtil.getEntityCollision.

[warjort]

Try simplying it by returning a boolean from that method and return true if optional.isPresent() is true.

[SirEnder125]

So the collision check is failing somewhere. Or its not failing but you are still somehow returning null?

Not sure, but it's definitely returning null. Checked with breakpoint...

Try simplying it by returning a boolean from that method and return true if optional.isPresent() is true.

Trying that now.

[SirEnder125]

I actually have to go in a few minutes, so after that we'll have to continue later... but I'll see what I can do

[SirEnder125]

Well we're getting some place-- optional.isPresent() is never true

[SirEnder125]

I'm assuming the problem is either min, max, or f?