EVO, the year’s biggest fighting games event, went down over the weekend, and in terms of news perhaps the biggest announcement was that not one but two games will be getting Rollback Netcode improvements over the next 12 months.
So in online multiplayer games, a big part of allowing everyone to play together is the way the game registers everyone’s actions at the same time. When a person in Canada is playing someone in Germany, they’ll both be pressing buttons in their own homes, and the game needs to pick up those inputs, apply them to the game and have them play out in a way that makes the whole thing look as seamless as though they were playing with (or against) each other in the same room Different games (and different genres) handle this differently, depending on how important speed and accuracy is to the player’s experience, but one type of input recognition that’s especially important to anyone playing a fighting game where every frame and millisecond can mean the difference between victory and defeat is called Rollback Netcode.
Rollback Netcode doesn’t rely on waiting for everyone’s input before registering actions; instead it lets both players press their buttons and see the action play out instantly without lag or delay, as though they were playing offline. In the downtime between that and the opponent’s action arriving, the game basically guesses what was going to happen next. If it guessed right the game continues with nobody noticing, and if it was wrong, it checks down to play out the action that the other player actually made, which sometimes involves a little “teleporting”. The very helpful video below, by Code Mystics, explains how Rollback Netcode works, and how in fighting games its speed and accuracy make it so superior to the more traditional Input Delay
Source: This news is originally published by kotaku