GAR rules at ZakStunts (draft)

This document is a draft which is being reviewed by the community. Feel free to share your impressions at the shoutbox or at the forum topic dedicated to it.

These are the rules for laps on the ZakStunts GAR scoreboard. They are primarily based on Marco's GAR demo video, while incorporating precedents established over the years in GAR races and other no-shortcuts competitions.

0. Introduction

GAR is a way of enjoying a Stunts track though an experience more akin to conventional racing. In many ways, it sharply contrasts with the no-holds-barred competition of the main ZakStunts scoreboard: no replay handling, no glitch chasing, no shortcuts, follow the yellow line.

GAR stands for "Gentlemen's Agreement Rules" The name is meant to reflect how compliance with the extra rules is primarily a matter of mutual trust between the racers, which is especially true with respect to no replay handling without video recordings. The concept is due to Marco, who introduced it to the ZakStunts community on the eve of the 2015 season. A parallel GAR scoreboard was eventually added during the 2016 season, in ZCT178. Since then, GAR racing has become a regular fixture at ZakStunts.

The GAR driving rules, which forbid shortcuts and a number of other exploits, are remarkably strict, and differ in subtle ways from earlier no-shortcuts or OWOOT rule sets. That being so, rule interpretation questions come up with some regularity. This document is meant to be a reference, to be checked when it is not clear whether a particular section of a GAR lap is valid.

1. Replay management

1.1. No replay handling: a GAR lap must be driven continuously, in a single pass from the start to the finish line. All forms of pausing, rewinding or reloading are forbidden.

1.1.1. This rule covers mechanisms both internal to Stunts, such as the replay system, and external to it, such as emulator save states.

2. Driving rules: general principles

2.1. Preamble: The GAR driving rules aim at approximating a realistic racing experience, while making reasonable allowances for the peculiarities of Stunts physics and the influence of events beyond the driver's control.

2.1.1. In this document, the driving rules will be presented in two parts, the first one being comprised of a set of general principles, and the second one, of rules about track elements. The track element rules are meant to implement and clarify specific aspects of the general principles, and take precedence over them should they ever be found into conflict.

2.1.2. The rules do not distinguish between intentional or unintentional violations, nor between advantageous and disadvantageous ones.

2.2. Definitions

2.2.1. Track: For the purposes of these rules, the track consists of the road and other surfaces unambiguously meant by the game designers to be driven on as part of the valid paths in a circuit. The limits of the track are defined by the game graphics. The term track area will be used to refer to the 900-tile square in which a track is set up.

2.2.2. Airtime: Time spent with no part of the car in contact with the ground or with any other non-vertical surface. Airtime can be identified visually or, in some circumstances, by changes in the behaviour of the car.

2.3. OPOOT: There must, at all times, be at least one pixel of the car on or over the track.

2.3.1. On or over: To be on the track is to be in direct contact with the track surface. To be over the track is to be directly above but not in contact with it, as, for instance, when a car is mid-flight above the road after a jump.

2.3.2. Pixel: Any part of the car being visually on or over the track suffices for the rule to be followed, even if said part amounts to a single pixel. Additionally, visual adjacency (neighbouring pixels) between car and track is enough, with overlap not being necessary. (This aspect of the rule is more liberal and easier to verify than in the traditional OWOOT codes of no-shortcuts Stunts racing.)

2.4. The standard camera angle: Verification of whether the OPOOT rule has been followed is done by watching the lap replay using the F3 camera, directly overhead (that is, at the highest camera position, ten key presses upwards from the default), centered (that is, three key presses rightwards from the default) and at the default zoom. (That is the standard camera angle originally established by Mingva for the IRC competition.)

2.5. Follow the yellow line: The track centre line (often referred to as the yellow line, after its colour on most asphalt track elements) should be broadly followed at all times.

2.5.1. No skipping of stunts: While the OPOOT rule forbids shortcuts that involve leaving the track and driving on or over grass or water, the yellow line rule outlaws shortcuts performed within the track limits. In particular, it rules out skipping major parts of stunt elements, such as the helical turns of l/r corks, u/d corks and loops. Edge cases in which it is not immediately clear whether some feature of a track element counts as a major part of it will be covered in the rules about specific track elements.

2.5.2. No dual-way switching: Whenever there is a split, the yellow line always follows each path from beginning to end. Dual-way switching (that is, changing paths between a split and a rejoin) is therefore forbidden.

2.5.3. No wrong way driving: The yellow line has a single direction. That being so, wrong way driving is forbidden.

2.6. No collision bugs: It is not allowed to exploit glitches and edge cases of the game physics to move through solid objects, nor to gain speed or airtime by colliding with vertical surfaces.

2.7. Miscellaneous exploits: There are a handful of tricks which involve drifting away from the track or the yellow line without unambiguously violating rules 2.3, 2.5 and 2.6. Some of those tricks are outlawed for being against the spirit of the rules, in which case they will be explicitly noted as such in the track element rules.

2.7.1. The following track elements have additional restrictions which fall under the scope of this rule: loops (rule 3.40.2), tunnels (rule 3.42.1), pipes (rules 3.44.2, 3.44.4 and 3.44.5), l/r corks (rule 3.55.2), highways (rule 3.6d.2) and slalom blocks (rule 3.73.2).

2.8. Illusion tracks: Certain track design techniques involve incomplete track elements, nonstandard track continuity, or otherwise make some of the usual driving rules inapplicable. Tracks with such features are generally known as illusion tracks. In such cases, either the track designer or the competition management will provide rulings on how the GAR rules are to be interpreted in the affected track sections. Such rulings should follow, as much as reasonable, the spirit of the general principles presented here.

2.9. Car behaviour is not restricted: The GAR rules place no restriction on car behaviour, as far as all other rules are followed. In particular, neither powergear, nor shifting tricks, nor magic carpets cause a lap to be invalid.

3. Driving rules: track elements

3.00. Preamble: The following rules about track elements includes both restrictions and explicit allowances of specific tricks and driving lines. They are grouped by track element, with the lowest unused element hexadecimal code to which the rule applies being used for indexing.

3.00.1 The rules in this section are not meant to be exhaustive. Situations not covered by them will be evaluated according to the general principles in section 2.

3.04. Straight roads

3.04.1. Hill slope delimiters: The beige delimiters on straight road elements placed on hill slopes are not considered part of the track.

3.0a. Large corners (including splits)

3.0a.1. Kerbs: The red and white kerbs on the inside of large corners are not considered part of the track.

3.22. Bridges (all kinds)

3.22.1. Bridge wall tricks: Any trick which involves driving through or hanging off the outside of a bridge wall is forbidden as a collision bug exploit. This rule applies to all kinds of bridges, and also to ramps and u/d corks.

3.24. Ramps (all kinds)

3.24.1. Ramp edge tricks: Using collisions against the side edges of a ramp to get airtime or to avoid falling off the track is forbidden as a collision bug exploit.

3.24.2. Jumps over gaps: When jumping off a ramp over an empty or scenery tile, the whole of the tile being jumped over counts as track.

3.24.3. Jumps over track elements: Whenever how to apply the yellow line rule isn't immediately obvious, the rules about specific track elements specify whether they can be jumped over.

3.28. Banked roads

3.28.1. Airtime from banked roads: It is allowed to get airtime from the track surface on entry, exit or any other point of a banked road.

3.28.2. Banked road edge tricks: Using collisions against the outer edge of a banked road to get airtime or to avoid falling off the track is forbidden as a collision bug exploit.

3.3c. Chicanes

3.3c.1. Fast grass: Only the dark grey surface in chicanes counts as part of the track, regardless of the fast grass bug.

3.40. Loops

3.40.1. Loopcuts: All kinds of loopcut are forbidden as, at a minimum, violations of the yellow line rule. A loop must be driven following the yellow line, with the car being upside down at its highest point.

3.40.2. Ascending loop leg: Contact with the ascending loop leg is only allowed if the loop is subsequently driven in full, following the yellow line. In particular, this rule forbids using the ascending leg to get airtime upon exiting a loop.

3.40.3. Jumping over loops: It is forbidden to jump over a loop.

3.42. Tunnels

3.42.1. Tunnel roofs: It is forbidden to drive on, land or touch tunnel roofs.

3.42.2. Jumping over tunnels: It is allowed to jump over tunnels, as long as no contact is made with the tunnel roof.

3.44. Pipes

3.44.1. Pipe entry wall tricks: Using collisions against the edge of pipe walls on its entry to get airtime or avoid leaving the track is forbidden as a collision bug exploit.

3.44.2. Pipe roofs: It is forbidden to drive on, land or touch the outside of pipe roofs.

3.44.3. Jumping over pipes: It is allowed to jump over pipes, as long as no contact is made with the outside of the pipe roof.

3.44.4. Airtime on pipes: It is forbidden to use the curvature of the inner surface of a pipe to get airtime, be it by inducing a hop, dropping from the upper half of the pipe, launching the car from the pipe exit, or by any other means.

3.44.5. Pipe obstacles: It is forbidden to use pipe obstacles to gain airtime. Driving on their top, however, is allowed.

3.44.6. Pipe inner surface: It is allowed to drive on any part of the inner cylindrical surface of a pipe.

3.4a. Crossroads

3.4a.1. Road surfaces: All road surfaces in a ground-level crossroad count as part of the track, regardless of track continuity.

3.4b. Splits (all kinds)

3.4b.1. Road surfaces: All road surfaces in a split or rejoin count as part of the track, regardless of track continuity.

3.55. L/r corks

3.55.1. L/r cork cuts: All kinds of l/r cork cuts are forbidden as, at a minimum, violations of the yellow line rule. An l/r cork must be driven following the yellow line, with the car being upside down at its highest point.

3.55.2. L/r cork entry and exit: On both entry and exit of a l/r cork, at least one pixel of the car must cross the line at which the curved surface of the cork meets the road. In particular, this rule forbids drifting leftwards when exiting an l/r cork in order to get airtime.

3.55.3. Jumping over l/r corks: It is forbidden to jump over a l/r cork.

3.6d. Highways

3.6d.1. Jumping over highway dividers: Neither the grassy surface nor the walls of highway dividers are considered part of the track. Jumping over them is forbidden unless there is at least one pixel of the car over the asphalt.

3.6d.2. Landing on highway dividers: Driving on or landing from a jump on any part of a highway divider is forbidden, even if the car is partly on or over asphalt.

3.6d.3. Highway divider collision bugs: Using collisions against any part of a highway divider to get airtime or avoid a crash by having the car deflected upwards is forbidden as a collision bug exploit.

3.73. Slalom blocks

3.73.1. Driving through slalom blocks: Moving through any part of a slalom block is forbidden as a collision bug.

3.73.2. Driving around the outside of slalom blocks: It is forbidden to drive on the thin strip of asphalt directly between a slalom block and the edge of the road. This rule disallows dodging a slalom block by driving around its outside.

3.73.3. Jumping over slalom blocks: It is allowed to jump over a slalom block.

3.75. U/d corks

3.75.1. U/d cork jumps: The yellow line must be followed on an u/d cork by driving the spiral turn in its entirety. It is forbidden to, by any means, jump over an u/d cork wall.

4. Miscellaneous

4.1. It is recommended that racers verify their GAR laps for any violations of the driving rules in sections 2 and 3 before posting them. A typical way of carrying out such a verification is watching the replay at double speed using the standard camera angle from rule 2.4, pausing and checking frame by frame wherever it is not obvious the rules are being followed.

4.2. Ambiguities and situations not covered by these rules should be brought to the attention of the competition management, who will issue a ruling guided by the general principles of the GAR rules and, if need be, consult with the community and amend the rules.

4.3. All rules of the main ZakStunts competition which do not conflict with these GAR rules remain in effect on the GAR scoreboard.

Appendix A: Version history

2021-03-24: Initial draft release.

Submitted by Duplode on 2021-03-24.