[1.9.4][SOLVED] Levitate entity.

[Wulfre]

I am trying to levitate entities that are within a radius from the player when a related item is right clicked with (not yet implemented -- currently tries to levitate as soon as a mob is within the radius).

The idea is to gradually move them into a position that is two blocks above the player, but no mobs seem to be reacting to EntityMob#motionY.

If I use EntityMob#setPositionAndUpdate they will jerk between their original location and the new location every time the AI tries to preform a task.

Another implementation I am planning is to have any mobs that are being levitated to move synchronously with the player, if anyone has insight on that. Not necessarily the actual code, but a rough idea on how to accomplish it.

 

public class ItemFissuredLimiter extends Item
{
    public ItemFissuredLimiter()
    {
        setMaxStackSize(1);
        setCreativeTab(KinesisReference.KINESIS_TAB);
    }

    public static int grabRadius = 5; // Blocks.
    public static int grabLimit = 5; // Mobs.
    public static int grabDuration = 10; // Seconds.

    @Override
    public ActionResult<ItemStack> onItemRightClick(ItemStack itemStackIn, World worldIn, EntityPlayer playerIn, EnumHand hand)
    {
        return super.onItemRightClick(itemStackIn, worldIn, playerIn, hand);
    }

    @Override
    public void onUpdate(ItemStack itemStackIn, World worldIn, Entity entity, int someInt, boolean someBoolean)
    {
        EntityPlayer playerIn = (EntityPlayer) entity;

        if(worldIn.isRemote && playerIn.getHeldItemMainhand() == itemStackIn)
        {
            // Create bounds around the player, based on the grab radius of the limiter, to check for entities in.
            double playerX = playerIn.getPosition().getX();
            double playerY = playerIn.getPosition().getY();
            double playerZ = playerIn.getPosition().getZ();

            int radiusHeightDifference = grabRadius - KinesisReference.PLAYER_HEIGHT;

            BlockPos posMin = new BlockPos(playerX - grabRadius, playerY - grabRadius, playerZ - grabRadius);
            BlockPos posMax = new BlockPos(playerX + grabRadius, playerY + radiusHeightDifference, playerZ + grabRadius);
            AxisAlignedBB radiusBox = new AxisAlignedBB(posMin, posMax);

            // Check for entities that are both in the grab radius and are mobs.
            List<EntityMob> mobsInRadius = worldIn.getEntitiesWithinAABB(EntityMob.class, radiusBox);

            // Levitate entities that are within the required radius while restrictions are not yet met.
            for(EntityMob mob : mobsInRadius)
            {
                // Don't levitate boss mobs, that is silly.
                if(mob.isNonBoss())
                {
                    double mobX = mob.getPosition().getX();
                    double mobY = mob.getPosition().getY();
                    double mobZ = mob.getPosition().getZ();

                    System.out.println(mob);
                    System.out.println(mob.motionY);

                      mob.fallDistance = 0;

                    if(mobY < playerY + 2)
                    {
                        mob.motionY = 0.2;
                    }
                    if(mobY > playerY + 2)
                    {
                        mob.motionY = -0.2;
                    }
                }
            }
        }
    }
}

[Wulfre]

Check out what the levitation potion does.

 

I tried looking for that, but I could not find the class for it in the vanilla library.

[Wulfre]

There is no class. The Potion instance is stored in

MobEffects.LEVITATION

. Search for where that is used.

 

I realized that after following the usages in the potion class. Thank you.

[Draco18s]

Stop using static variables any class-level variables at all inside your item class.

[Wulfre]

Stop using static variables any class-level variables at all inside your item class.

 

I was using some of the variables for tick calculations in some other class and never set them back. Thank you for reminding me.

 

Now that I look at it again, all your code is only running client side. This is bad.

 

Would you mind explaining to me how to make things run server side? I took some recommendations from a friend while writing this -- mostly on checking if the world is remote, which is what I am assuming is the issue.

EDIT: I changed world.isRemote to !world.isRemote and everything works as intended now.