I want to prevent all animations that happen when the left mouse button is pressed. The problem that I can't find a way to prevent the up-and down movement of the item when the item "recharges". The feature was introduced in 1.9 (I think) and is indicated with a little sword below the crosshair.

 

Edit: solved by overriding Item::getAttributeModifiers

@Override
public Multimap<String, AttributeModifier> getAttributeModifiers(EntityEquipmentSlot slot, ItemStack stack)
{
   Multimap<String, AttributeModifier> multimap = super.getAttributeModifiers(slot, stack);
   multimap.put(SharedMonsterAttributes.ATTACK_SPEED.getAttributeUnlocalizedName(), new AttributeModifier(ATTACK_SPEED_MODIFIER, "Tool modifier", 1024, 0));
   return multimap;
}

 

 

If you put the item in the off-hand and back in the main-hand the cooldown is back until you switch to a different item (or update the stack somehow else) Is there an event that is thrown when switching items between hands? Also the tooltip of the item now shows 1014 as attackspeed.

 

My second approach is to set the SharedMonsterAttributes.ATTACK_SPEED of the player as high as possible when the item is held because it is used to calculate attack speed of the player (EntityPlayer::getCooledAttackStrength) and then set it back to 4 when a different item is held. This is really hackey and exactly what I wanted to prevent by using the new rendering system but it's better than nothing.