A wallclip refers to any interaction where the player collides with a wall and gains height without losing significant speed.

Wallclip

Other names Clip
Class Glitch
Type Wall interaction
Date found 2008
Theoriser(s) Unknown
Discoverer(s) Unknown?
Timesave N/A

Wallclips are commonly used to obtain large amounts of vertical speed, enabling the player to clear tall walls, gaps, and objects. High wallclips are classified as a glitch, and were discovered in 2008. They are performed by travelling parallel to a wall (or very close to parallel) at high speed, having high bike pitch, and touching the wall having obtained at least 5 frames of airtime beforehand.

Wall collision behaviour

When you hit a wall, the effect it has on your speed depends on the direction you're moving in relative to the facing direction (the normal) of the wall. The following things also happen:

  • Any drift or wheelie will be cancelled.
  • When colliding with a wall, your IV vector is updated to be equivalent to your horizontal facing direction. Existing EV may be absorbed or redirected parallel to the wall’s plane.
  • When colliding with a wall with at least 5 frames of airtime, your IV vector is updated to be equivalent to your horizontal and vertical facing direction.

Specifically, if the wall is facing towards you (more than 90° away from your direction of motion), colliding with it will kill most of your IV, and you will be bounced backwards slightly with EV. If the wall is facing away from you (less than 90° away from your direction of motion), you will maintain most of the speed you had prior to collision - excluding speed loss from the wall automatically cancelling your wheelie.

From a mathematical perspective, if the dot product of the player's total velocity vector and the wall's normal vector is positive, then no speed is lost. Colliding with the wall in this way is essential for a successful wallclip.

(To do: visuals with vectors).

Some wall clips may be easier than others due to constraints from other wall faces. For example, the N64 Sherbet Land finish line pole has a hexagonal cross section. In order to clip one of the corners without being parallel to either face, you must have very precise QM that allows you to bypass the wall facing towards you, and clip off of the wall facing away.

On the other hand, KMP objects that use wall collision (most trees, pipes, boxes) have the unique property of colliding with specific “hull points” on the vehicle instead of the regular hitboxes. This means that you have way more leniency to corner clip objects because the points make up a smaller area that is more likely to pass through the front wall and collide with the back wall in order to corner clip.

Clip height/distance factors

The status of high clip or low clip is determined by your airtime when contacting the wall and vertical pitch rotation. Wall clips are not exclusive to bikes, but bikes are capable of significantly higher clips due to the wheelie’s effect on pitch rotation.

There are three main factors which influence wallclip height and distance:

1. Horizontal speed

Being at max horizontal speed when clipping the wall will increase clip height and distance. Conversely, clipping at a low speed decreases clip distance and height.

2. Vehicle pitch

Similar to parabolic projectile motion, clipping with extreme bike pitch will increase your clip height, but will sacrifice distance. There exists a pitch which balances optimising for both height and distance, which is especially useful for wallclips in 3lap runs where movement needs to be optimised (i.e., clearing the top of a wall as low as possible, spending minimal time on the clip setup). Normally, doing a double-wheelie before a wallclip, along with well-timed shroom usage, provides enough bike pitch for most wallclip shortcuts in the game. Barrel roll wallclips allow for unrestricted pitch rotation and are particularly useful for maximising wallclip height, or clearing walls when double-wheelie setups aren't sufficient.

3. Vertical speed/airtime

Wallclip height is also affected by the vertical speed (Y speed) you have when clipping.

You can get vertical speed on flat ground by getting a bounce. This can be easily achieved by reversing, wheelieing, and giving the bike sudden acceleration due to a shroom boost. Because gravity constantly accelerates you towards the ground, your vertical speed will decrease on each frame of bounce airtime.

This means it would be ideal to clip on the first frame of airtime, however, when clipping a wall with <5 frames of airtime, you will not gain much height at all - even with the pitch rotation of a wheelie - due to the game's code. These are known as low clips. Low clips are primarily used to start slip drifts (known as clip drifts when initiated in this fashion) because they often give a small pocket of airtime - importantly, a pocket with fewer airtime frames than you would get otherwise from hopping. These are used frequently in the N64 Sherbet Land No Glitch 3lap TAS.

When clipping a wall with ≥5 frames of airtime, the IV vector is updated to be equivalent to your horizontal and vertical facing direction. For a standard wallclip on regular road types, hitting the wall with an airtime of 5 or more frames is essential for getting a high clip to cross large gaps and clear high clips.

Typically, clipping with exactly 5 frames of airtime results in the highest possible clip. This satisfies the ≥5 airtime condition, whilst also minimising loss of vertical speed due to gravity.

Wallclip types

High clip

Low clip

Hop clip

Delay clip

Floor clip

Slippery road wallclips (see below)

ODB clips (see below)

Slippery road wallclips

Outside-drifting bike (ODB) clips

History

TAS BKTs

Applicable categories
Type Unrestricted No Ultra No Glitch
3lap Yes Yes Banned
Flap Yes Yes Banned

Runs:

Relevant code