= HowTo: Tickable =

A tick is one frame or one iteration of the main-loop. Classes can be called every tick. This is achieved by inheriting from [wiki:doc/Tickable] and implementing the {{{virtual void tick(float dt)}}} function. ''dt'' is the time '''in seconds''' passed since the last tick.

*.h file:
{{{
#include "objects/Tickable.h"

class MyClass : public Tickable
{
    public:
        virtual void tick(float dt);

    private:
        Vector3 position_;
};
}}}

*.cc file:
{{{
void MyClass::tick(float dt)
{
    // let the object move with 100 units per second in positive x direction:
    Vector3 velocity(100, 0, 0);
    this->position_ += velocity * dt;

    // call tick(dt) of the parent class:
    SUPER(MyClass, tick, dt);
}
}}}

(See [wiki:howto/Super this] for more information about the SUPER macro.)