What Does Rollback Netcode Mean?
There are over two billion gamers worldwide as the pandemic resulted in people staying indoors. As a result, gaming became much more appreciated. Those who developed their skills during the lockdown probably learned something about gaming, one of which is rollback netcode. Rollback netcode is crucial in fighting games and if you are thinking of trying this genre of entertainment, here is all you need to know about it.
Rollback Netcode and How It Works
Gamers experience different issues when gaming. Gamerant explained that latency is the highest form of frustration for players. Some of the concerns for die-hard gamers include input latency which is the delay between pressing a button and the action being processed to be displayed in-game. It is important because it ensures that all the players have access to the same display at any given time. You could also experience network latency when you send information, but there is a delay in the person on the other end receiving it. Another issue is lag freeze due to a sudden surge in network latency, such as one player’s display freezing as it waits for the gamer’s connection on the other end to catch up.
Rollback netcode helps to solve the problem of lag freezes. As an alternative to freezing the game while awaiting a good connection on the other end, the game proceeds by predicting what the other player would have input. If the predictions are correct, the game continues without a hitch. However, once the connection is back on again and the player’s real inputs are not similar to what the game predicted, the game rolls back to adjust to the correct gameplay. As Arstechnica insists, the major requirements for rollback netcode to work are saving and loading a variety of game states very fast so that players will not even notice there was a lag. The ability to react rapidly to such lags is only possible due to a game’s serialization. The article explains that the game must serialize every game frame and store it to ensure that all the players are in sync. Showing one player that he is supposed to react to a different game frame than the one he is supposed to due to the frames not being in sync will cause excessive delays depending on the network delay across various game frames. The more the game frames, the more the game state needs to roll back, which can be very frustrating.
The Inspiration behind Its Invention
They say necessity is the mother of invention, and true to this expression, Tony Cannon invented the rollback netcode. In an interview with Gamasutra, Cannon revealed that he had been rooted in the arcade culture. In the mid-90s, he felt the culture was slowly fading. As a pro-level fighting gamer, Cannon was excited when Capcom announced the release of “Street Fighter II: Hyper Fighting” to connect players who could no longer meet at arcades. Unfortunately, it did not meet his expectations due to the many glitches and lags that made enjoying the game impossible. His love for gaming could not allow him to sit back and wait until changes were made, so he decided to improve the game. As Gamasutra continues to explain, Cannon thought it best to insert the lag at the beginning of the opponent’s move. The other option would have been to insert the delay between the press of a button and the start of a move. Although it is not flawless because you will still experience some glitches, it is much better than what he had encountered before. Besides, the timing is the same, which is very important to proficient gamers. Cannon also disclosed to Game Developer that he wrote GGPO (Good Game, Peace Out) to solve the lag problem without sacrificing the other game properties. Therefore, he ensured that a local player’s avatar is as responsive when playing online as when gaming offline. With GGPO, Cannon also ensured that the predictions were correct most of the time to avoid constant rewinds or rollbacks. It took him eight months to develop the first version, and then more time passed before gamers could enjoy this new invention because Canon could not find a company willing to try out his concept.
The Importance of Rollback Netcode
Polygon published that most gamers use delay-based netcode despite the advancements in technology that resulted in rollback netcode. In delay-based netcode, both players have their input delayed by a few frames. This compensates for the unavoidable lag time accompanied by the data transmission between players who are miles apart. The author explains that the delay changes the feel of the game because it makes a big difference between rounds fought in person and online. It is especially boring to professional gamers, who expect speed because they are thrown off balance once the strategy they planned on using is lost in transmission. Thus, one has to adapt to the constant shifting in the netcode.
Rollback netcode, therefore, never lets players put their best foot forward without being at a disadvantage by such lags that compromise their strategies in winning. Esports Talk argued that any slight variable would put players at a disadvantage. For this reason, even when tournaments are held in person, there has to be a flawless LAN connection. The connection eliminates any chance of such lags being experienced between players. Regardless of how good rollback netcode is that gamers cannot even imagine games without it, not all fighting games have embraced it. Some insist on using the old-fashioned delay-based netcode. Rollback netcode has its downsides, such as being too expensive and complex, which could deter some gaming companies from adopting it. Besides, it is not seamless because Antsstyle argues that rollback is poor at handling large lag spikes.
