public void CheckAndApplyUnitCollision(PhysicalUnit other)
{
if (!Collides)
{
return; //don't check collision if unit shouldn't collide
}
//special shattered collision detection
if (_lifeState == LifeState.Shattered)
{
tempRec.Width = _hitRect.Width / ICE_DIVISIONS;
tempRec.Height = _hitRect.Height / ICE_DIVISIONS;
for (int i = 0; i < ICE_DIVISIONS; i++)
{
for (int j = 0; j < ICE_DIVISIONS; j++)
{
tempRec.X = (int)(_fragments[i, j].Position.X - tempRec.Width / 2);
tempRec.Y = (int)(_fragments[i, j].Position.Y - tempRec.Height / 2);
if (tempRec.Intersects(other.HitRect))
{
Vector2 fVel = _fragments[i, j].Velocity;
float fMass = (float)Mass / (ICE_DIVISIONS * ICE_DIVISIONS);
temp = other.Velocity;
other._velocity = (other._velocity * (other.Mass - fMass) + 2 * fMass * fVel) /
(fMass + other.Mass);
_fragments[i, j].Velocity = (fVel * (fMass - other.Mass) + 2 * other.Mass * temp) /
(fMass + other.Mass);
}
}
}
return; //ignore normal collision detection
}
//check if fire should be transferred
float dist = XnaHelper.DistanceBetweenRects(HitRect, other.HitRect);
if (dist < FIRE_SPREAD_DISTANCE)
{
if (_statusEffects.Fire > other._statusEffects.Fire)
{
StatEffect transfer = new StatEffect()
{
Fire = FIRE_SPREAD_FACTOR * dist / FIRE_SPREAD_DISTANCE * _statusEffects.Fire
};
other.ApplyStatus(transfer);
ApplyStatus(transfer * -FIRE_SPREAD_LOSS);
}
}
if (XnaHelper.RectsCollide(HitRect, other.HitRect))
{
temp = other._velocity; //temp is a static reusable vector
other._velocity = (other._velocity * (other.Mass - this.Mass) + 2 * this.Mass * this._velocity) /
(this.Mass + other.Mass);
this._velocity = (this._velocity * (this.Mass - other.Mass) + 2 * other.Mass * temp) /
(this.Mass + other.Mass);
}
}