Jumping
Learning paths through this topic
Does a jump really clear a tripwire or a low trap trigger?
Hidden wires and floor triggers are common in survival worlds, and players love to hop over them. Checking only the top of the jump says every jump works, and checking the landing spot misses the moment the feet cross the line. Here is how to test the arc over the width of the feet.
A group of hopping enemies that do not all jump in lockstep
A pack of hoppers that all leave the ground on the same frame looks fake and is also easy to dodge in one go. Random timers per enemy break repeatability, and timers started at spawn drift together after a pause. Here is a schedule that spreads them out and stays exact.
A jetpack with fuel that runs out in the middle of a frame
Hold the button and rise, let go and fall, run dry and drop. Simple until the thrust is too sudden to control, the tank refills in mid-air, or the last drop of fuel gives a full kick. Here is a jetpack that starts softly and ends exactly when it should.
Cancel the end of an attack with a jump, but only if the attack hit
Skilled players love to escape the slow ending of a sword swing by jumping. Allow it on every swing and nobody ever pays for a miss; allow it never and the fights feel stiff. Here is the rule that rewards a hit, once, and for a short time.
Jumping on a steep hill should not launch you sideways or into the slope
On open terrain hills are everywhere, and a jump that ignores the slope behaves strangely: straight up lands you uphill and feels sticky, along the surface flings you off the side. Here is a way to aim the jump so it feels the same height everywhere, and where it must refuse.
Jumping off a moving platform: the character should carry its speed
Standing on a lift or a moving floor, the character moves along. Jump, and either it drops straight down behind the platform or it flies off too fast and cannot be steered back. Here is what to carry over, what to leave, and how it fades.
Set a jump by how high and how long it should be, not by guessing numbers
Tweaking gravity and jump strength by trial and error ends with jumps that are floaty on the way up and heavy on the way down, or that no longer fit your level. Here is how to start from what you want and get the numbers out.
Wading through mud or swamp should weigh down the jump, gradually
A swamp that either lets you jump normally or locks you in place feels flat. Players want to feel the ground pulling at them the deeper they wade, and to find a way out at the end. Here is a smooth scale from shallow to stuck, and the one number people forget.
Jumping in a low cave tunnel without getting stuck in the ceiling
In caves and player-built bunkers the ceiling is often lower than the character is tall. Pressing jump there makes the character stand up through the roof, bonk every frame or buzz up and down. Here is how to decide whether to stand, how high a hop is still possible, and when to say no.
Jumping off a ladder or vine without instantly grabbing it again
Hit jump on a ladder and the character either drops like a stone, floats up the rungs again, or sticks to the same ladder the moment it leaves. Here is what the leap must carry, how a held direction changes it, and the short rule that stops the instant re-grab.
Jumping out of a slide should carry the speed, but not chain forever
A slide that turns into a jump is a satisfying way to cross open country, until players learn to repeat it and out-run everything, or the jump comes out as if no slide had happened. Here is what the jump should inherit, when a slide is too slow to count, and the pause that stops the exploit.
A bounce pad that flings players, animals and items once per visit
A pad that launches whatever touches it works fine until a mob stands on it, an item rolls over it twice or someone drops back onto it mid-flight and is shot again and again. Here is how to remember who was already launched, when to arm the pad again for them, and how hard to throw.