Punch and impact
Learning paths through this topic
Other players creep to one side because positions are squeezed into few bits
To save data, positions are packed into small whole numbers, and the way the number is rounded decides whether remote players shimmer around the truth or slowly slide in one direction. Here is the packing, how many bits a given map size needs, and what must happen when someone leaves the map.
Players who stopped still drift a little on other screens
To save data, a game sends a player's position only when it changed noticeably, which works until the player stops just short of the threshold and everyone else sees them standing in the wrong place for the rest of the game. A small extra rule fixes it. Here are the rules for when to send.
I aimed right at them but the shot missed in an online game
What you see on your screen is already a little old by the time your shot reaches the host, so the target has moved on. Fair games check the shot against where the target was when you pulled the trigger. Here is how far back to look, and the limit that stops fast connections from being punished.
Standing on a friend's head, I slide off whenever they walk
A partner who carries you should take you along, but if you simply stand on a body that moves, you stay behind and fall off, or you shake against it. The trick is to move you by what they moved, and to remember some of that speed when you step off. Here is the rule and the check for being on top.
A thrown friend steers away at once and the throw feels weak
A throw that the thrown player can cancel with a key press is not a throw. But a player who cannot steer at all feels robbed. The answer is a short moment with no control and then a gradual return. Here is the launch speed, including what the thrower's own running adds, and the control curve.
Other players spin all the way round when they turn slightly
A character looking just past north and then just past north on the other side should turn a hair, but a plain average of the two numbers sends it spinning the long way round. Angles need their own kind of blending. Here is the rule, the exact tie case, and why one extra step is needed after it.
A heavy crate that needs two players but moves too fast with both
A crate meant for teamwork should not move for one player, should crawl for two pushing weakly, and should stand still when they push against each other. Adding the pushes up gets this nearly right, but two traps remain: a tie that jitters and a speed that has no ceiling. Here is the rule with a good starting weight.
Two players' games slowly drift apart without any lost message
If both computers run the same game from the same inputs, they should always agree. They do not, because tiny rounding differences in decimal numbers add up until a character stands in two places. Doing movement in whole numbers makes the results identical everywhere. Here is the number format and the rounding rule that must never change.
A parry that is demanding but fair, with good and perfect grades
A parry that opens on every button press is spammed and trivial, and one with a tiny window feels broken on a slow screen or a wireless pad. Here is how long the window should be, how to make up for delay in the controller, and how to stop mashing.
Enemies that stagger after enough hits, but cannot be stunned forever
A hit reaction every time makes tough enemies silly, and none at all makes attacks feel weightless. A hidden resilience meter that fills with hits and drains when left alone solves the first; a short immunity after the stagger solves endless lock-in. Here are the numbers.
The button that closes a dialogue immediately starts the next conversation
Close a text box with the same button that opens it and the hero talks again at once, or a shop menu closes and the purchase repeats. Players call it a bug and feel they lost control. Here is a small rule about which buttons count after a menu, and which should carry straight on.
A fighter steps up to its target to strike and returns to exactly where it stood
In turn-based fights the attacker usually dashes forward, hits and goes back. Done by adding up small moves, it ends a little off its spot after a few rounds, or runs into its target. Here is a way to shape the motion so the hit lands at the right moment and the return is exact.