public ItemStack onItemUseFinish(ItemStack stack, World worldIn, EntityLivingBase entityLiving)
{
  Entity entity = ModMath.getMouseOver(Minecraft.getMinecraft().getRenderPartialTicks(), 0); // Gets entity that entityLiving is looking at

  if (entity != null && entity instanceof EntityLiving)
  {
    ((EntityLiving)entity).attackEntityFrom(DamageSource.MAGIC, 2.0f);
    ((EntityLiving)entity).setRevengeTarget(entityLiving);
  }

  return stack; 
}

 

Using item that has the implementation of the method above doesn't damage entity. Debugging it showed that attackEntityFrom() is called, code within if statement is executed but entity isn't attacked. I looked into Minecraft's files that use attackEntityFrom() and observed that they just call attackEntityFrom(), just one line of code(I assume that something else that can affect entity attacking process was called before attackEntityFrom() in that files). How can I solve this problem? How can I deal damage to entity?

Damaging the Entity (and all Entity related operations in general) must be done on the server side, yet your code is executing on the client (indicated by the usage of Minecraft class).

You would need to send a packet to the server to inform it about the action, then damage the Entity on the server.

2 hours ago, DavidM said:

Damaging the Entity (and all Entity related operations in general) must be done on the server side, yet your code is executing on the client (indicated by the usage of Minecraft class).

You would need to send a packet to the server to inform it about the action, then damage the Entity on the server.

Can I just change ModMath.getMouseOver(…) to make it be able to work only on server. And put everything in if (!worldIn.isRemote). Will it work?

Edited December 8, 20195 yr by AntonBespoiasov

I solved this problem. And I did it in pretty weird way. I add entity = worldIn.getEntityByID(entity.getEntityId()) after getting entity with ModMath.getMouseOver(…). The problem was in ModMath.getMouseOver(…).

7 hours ago, AntonBespoiasov said:

Can I just change ModMath.getMouseOver(…) to make it be able to work only on server. And put everything in if (!worldIn.isRemote). Will it work?

No. You are still reaching across logical sides.

Use packets.