clarified default of force(0,0)

[physics.git] / src / Entities / PhysicsEntity.cpp

#include "PhysicsEntity.h"
#include "../debug.h"

#include "../Vector2.h"

/// ***** Public Class Methods *****
PhysicsEntity::PhysicsEntity(const Vector2& pos)
    : Entity(pos), force(0,0), mass(1), CoR(1)
{

}
PhysicsEntity::~PhysicsEntity()
{

}

void PhysicsEntity::update(float time_step)
{
    position = positionAt(time_step);
    velocity = velocityAt(time_step);

    force *= 0;
}

Vector2 PhysicsEntity::positionAt(float time_step) const
{
    return force/mass / 2 * time_step * time_step + velocity * time_step + position;
}

Vector2 PhysicsEntity::velocityAt(float time_step) const
{
    return force/mass / 2 * time_step + velocity;
}

void PhysicsEntity::applyForce(const Vector2& force)
{
    this->force += force;
}

void PhysicsEntity::applyImpulse(const Vector2& impluse)
{
    velocity += impluse;
}