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Steering Behaviours v1.3

This simulation shows how vectors within Game Maker can create life-like movements. Using algorithmic steering behaviors produced by Craig W. Reynolds, I will demonstrate some of the most common steering behaviours. In later versions of this simulation, you'll start to see more complex behaviours combining multiple steering behaviours together.

Future Implementations:

- Seperation
- Crowded Path Following
- Queing
- Flocking
- Obstacle Avoidance

Below describes the behaviours currently implemented within the simualtion.

Seek:
The goal of this steering behaviour is to seek the location of the target. Instead of simply setting the direction of the vehicle to the target and applying speed, a steering force is applied that turns it towards the target's location instead.

Flee:
Using the similar concept to seeking, the vehicle will instead apply a steering force that turn away from the mouse location.

Pursue:
The pursuing behaviour is a more advanced version of seeking as it try to predict where the target will be few steps into the future. Setting this future location as the target instead will help make seeking the location much easier as it be able to 'cut' the target off at turnings.

Evade:
This behaviour is the opposite of pursue. Instead of trying to catch the target, the vehicle will try to predict where the pursuer will be a few steps into the future and attempt to flee from that location.

Arrive:
You may have found in the seeking demonstration, the vehicle travels right past the target. This is because the vehicle wants to travel at maximum speed even once it has reached the target causing it to move back and forward. The arrival behaviour instead creates a radius around the target that causes the vehicle to slow down gradually.

Wander:
This behaviour simulates random movement around the screen. We could simply set the direction of the vehicle to any value between 0-360 however this would not give a life-like feel, instead we want to choose a direction that is relative to the current direction but with an offset angle. By using this concept we generate a much better simulation.

Flowfield:
This steering behaviour takes a new approach by instead creating a grid of vectors. While the vehicle travels around the screen, it will check what the vector is below and recalibrate to match the direction. This can be very powerful and is used in some RTS games today. While units are moving across terrain, they will want to dodge hilly areas. Using a flow field, vectors could be created on these hills that point the unit away forcing the units to travel around it.

Path Following:
This behaviour attempts to steer the vehicle along the path. It first checks to see if the future location of the vehicle is outside the radius of the path. If this is the case, it will make use of the seek behaviour and navigate back towards the centre. If the vehicle is already on the path, no steering is required and will therefore travel at full speed in its current direction.