public void ProcessCollisions()
{
// if here is in transactional state - get out
if (!hero.CanCollide)
{
heroPrevBounds.Clear();
return;
}
colliders.Clear();
// tunneling prevention
if (!heroPrevBounds.IsZero())
{
// horizontal move
{
var d = hero.Bounds.X - heroPrevBounds.X;
if (d != 0)
{
float n = (int)Math.Abs(d / MaxSingleMoveX);
if (n > 1.0f)
{
var inc = MaxSingleMoveX * d / Math.Abs(d);
for (int i = 0; i < n && colliders.Count == 0; i++)
{
heroPrevBounds.X += inc;
FindCollisions(ref heroPrevBounds);
}
}
}
}
// vertical move
{
var d = hero.Bounds.Y - heroPrevBounds.Y;
if (d != 0)
{
float n = (int)Math.Abs(d / MaxSingleMoveY);
if (n > 1.0f)
{
var inc = MaxSingleMoveY * d / Math.Abs(d);
for (int i = 0; i < n && colliders.Count == 0; i++)
{
heroPrevBounds.Y += inc;
FindCollisions(ref heroPrevBounds);
}
}
}
}
}
// find objects we collided with
if (colliders.Count == 0)
{
FindCollisions(ref hero.Bounds);
}
heroPrevBounds = hero.Bounds;
if (colliders.Count == 0)
{
return;
}
// sort them by the amounth of intersection (descending)
colliders.Sort((t1, t2) => t2.Item3.CompareTo(t1.Item3));
for (int i = 0; i < colliders.Count; i++)
{
// process collision with the object
if (colliders[i].Item1.ProcessCollision(this, colliders[i].Item2))
{
// quit if collision was processed or go to the next object
break;
}
}
}