UpdateInvPartial

Update inv partial is used to send an update of an inventory that doesn't include the entire inventory. This is typically used after the first UpdateInvFull update has been performed, as subsequent updates tend to be smaller, such as picking up an object - only a single slot in the player's inventory would change, not warranting the full 28-slot update as a result.

A general rule of thumb for when to use partial updates is if the percentage of modified objects is less than two thirds of that of the highest modified index. So, if our inventory has a capacity of 1,000, and we have sparsely modified 500 indices throughout that, including the 999th index, it is more beneficial to use the partial inventory update, as the total bandwidth used by it is generally going to be less than what the full update would require. If, however, there is a continuous sequence of indices that have been modified, such as everything from indices 0 to 100, it is more beneficial to use the full update and set the capacity to 100 in that.

Below is a percentage-breakdown of how much more bandwidth the partial update requires per object basis given different criteria, compared to the full update:

14.3% if slot < 128 && count >= 255
28.6% if slot >= 128 && count >= 255
33.3% if slot < 128 && count < 255
66.6% if slot >= 128 && count < 255

While it is impossible to truly estimate what the exact threshold is, this provides a good general idea of when to use either packet.