Strafe-jumping

Strafe-jumping is a technique used to increase a player's speed in computer games based on the Quake engine. The technique is common in first-person shooters.

Strafe-jumping was a result of a bug in the code base of the 1996 first-person shooter video game Quake, but it was later decided to be kept intact, as it had become a standard technique used by players. The bug itself relies on mathematics: when pressing a direction key, the game adds a unit vector in that direction to the player's movement speed. The final sum, however, is never normalized - this means that by directing the avatar away from the current kinetic vector but within 90 degrees of it, the player can exceed its own top speed.

Strafe-jumping requires a specific combination of mouse and keyboard input. The exact technique involved depends on the game itself. In several games, there are entire maps devoted to this, much like obstacle courses.

The controls are typically as follows:

Done correctly, this will increase the player's velocity with successive jumps. Mastering this technique requires lots of practice. Sequential strafe-jumping is mainly a matter of muscle memory, as the maximum angle of mouse motion increases slightly with consecutive jumps. Another way to increase jump speed in Quake III is a circle jump where the player gets over 500 units/sec (standard runspeed is 320 units/sec).

In some games based on the Quake 3 engine, such as Call of Duty and Wolfenstein: Enemy Territory, fractional increases in jump height can be achieved by playing the game at higher frame rates.

The circle jump start is the action performed by the player at the start of strafe jumping, giving a sudden burst of speed, as opposed to gaining speed with regular strafe jumping. This technique is found to have worked best in Quake engine based games.

The movements are as follows:

Bunny hopping is a term used for different kinds of movement in games. There are two major usages of the term: In any first person shooter with jumping a player who jumps up and down to avoid being shot is sometimes called a bunny hopper. This is a very basic technique that only works against inexperienced opponents.

More advanced techniques known as bunny hopping use game physics to move faster than the base movement speed, combined with air-control (the ability to change movement direction significantly without losing speed while in the air). Techniques that gain speed without the ability to significantly change direction are often called Strafe-jumping. The methods used to achieve bunny hopping vary from game to game.

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