/// <summary>
/// Unlinks the specified child, providing no way to ensure they remain delinked.
/// </summary>
internal static void _SimpleDelink(LinkedDriftoid Parent, LinkedDriftoid Child)
{
Parent._LinkedChildren.Remove(Child);
Child._LinkedParent = null;
Parent.OnChildDelink(Child);
Child.OnParentDelink(Parent);
}
/// <summary>
/// Unlinks the specified child.
/// </summary>
internal static void _Delink(LinkedDriftoid Parent, LinkedDriftoid Child)
{
_SimpleDelink(Parent, Child);
// Apply a small impluse to ensure they stay delinked
Vector dif = Parent.Position - Child.Position;
dif = dif * (1.0 / dif.Length);
Parent._ApplyImpulse(dif);
Child._ApplyImpulse(-dif);
}
/// <summary>
/// Tries linking two driftoids.
/// </summary>
internal static void _Link(LinkedDriftoid A, LinkedDriftoid B)
{
int ind;
if (!A.IsAncestor(B) && !B.IsAncestor(A))
{
if (A._LinkedParent == null)
{
if (B._CanLink(A, out ind))
{
if (B._LinkedParent == null)
{
int dummy;
if (A._CanLink(B, out dummy))
{
return;
}
}
B._Link(A, ind);
return;
}
}
if (B._LinkedParent == null)
{
if (A._CanLink(B, out ind))
{
A._Link(B, ind);
}
}
}
}
/// <summary>
/// Called when this is added as a child of another driftoid.
/// </summary>
public virtual void OnParentLink(LinkedDriftoid Parent)
{
}
/// <summary>
/// Corrects (repositions participants) the link between a parent and child driftoid.
/// </summary>
internal static void _CorrectLink(LinkedDriftoid Parent, LinkedDriftoid Child, int Iter, Vector Difference, double Distance)
{
// Is there a problem
if (Math.Abs(Distance - Parent.Radius - Child.Radius) > 0.001)
{
// Equivalent to another problem...
Driftoid._CollisionResponse(Parent, Child, Difference, Distance, 1.0);
}
}
/// <summary>
/// Spawns the specified driftoid, out of nowhere. This should not be called during an update.
/// </summary>
public void Spawn(LinkedDriftoid Driftoid)
{
this._Driftoids.Add(Driftoid);
}
/// <summary>
/// Called when this acquires a new child driftoid.
/// </summary>
public virtual void OnChildLink(int Index, LinkedDriftoid Child)
{
}
/// <summary>
/// Gets if a link from the parent (which is a descendant of this driftoid) to the specified child is allowed.
/// </summary>
public virtual bool AllowLink(int Index, LinkedDriftoid Parent, LinkedDriftoid Child)
{
if (this._LinkedParent != null)
{
return this._LinkedParent.AllowLink(Index, Parent, Child);
}
return false;
}
/// <summary>
/// Gets if a link to the specified parent as a child is allowed.
/// </summary>
public virtual bool AllowParentLink(LinkedDriftoid Parent)
{
return true;
}
/// <summary>
/// Draws a "linker" between two linked driftoids. Driftoids and view should already be set up.
/// </summary>
public static void DrawLinker(LinkedDriftoid Parent, LinkedDriftoid Child)
{
_LinkerKey lk = new _LinkerKey()
{
ChildRadius = Child.Radius,
ChildBorderWidth = Child.BorderWidth
};
_LinkerTexture lt;
if (!_LinkerTextures.TryGetValue(lk, out lt))
{
_LinkerTextures[lk] = lt = _CreateTexture(lk);
}
Vector dif = Parent.Position - Child.Position;
Texture.Bind2D(lt.Texture.ID);
GL.PushMatrix();
GL.Translate(Child.Position.X, Child.Position.Y, 0.0);
GL.Rotate(dif.Angle * 180 / Math.PI, 0.0, 0.0, 1.0);
GL.Translate(-lt.ChildCenterOffset, 0.0, 0.0);
GL.Scale(lt.Size.X / 2.0, lt.Size.Y / 2.0, 1.0);
GL.Translate(1.0, 0.0, 0.0);
GL.Begin(BeginMode.Quads);
GL.Vertex2(-1.0f, -1.0f); GL.TexCoord2(0f, 0f);
GL.Vertex2(-1.0f, 1.0f); GL.TexCoord2(1f, 0f);
GL.Vertex2(1.0f, 1.0f); GL.TexCoord2(1f, 1f);
GL.Vertex2(1.0f, -1.0f); GL.TexCoord2(0f, 1f);
GL.End();
GL.PopMatrix();
}
/// <summary>
/// Gets a visual for a linker between to linked driftoids.
/// </summary>
public static Visual GetLinkerVisual(LinkedDriftoid Parent, LinkedDriftoid Child)
{
return new _LinkerVisual()
{
Parent = Parent,
Child = Child
};
}
public override bool AllowLink(int Index, LinkedDriftoid Parent, LinkedDriftoid Child)
{
return true;
}
public Structure(LinkedDriftoid Driftoid)
{
this._Driftoid = Driftoid;
}
/// <summary>
/// Indicates that a player is trying to manually delink a driftoid from its parent.
/// </summary>
public void TryDelink(Player Player, LinkedDriftoid Target)
{
if (Target.LinkedParent != null && Target.Reaction == null)
{
if (this.HasLinkControl(Player, Target))
{
LinkedDriftoid._Delink(Target.LinkedParent, Target);
}
}
}
/// <summary>
/// Gets if a link to the specified child is possible. Returns the index of the candidate.
/// </summary>
internal bool _CanLink(LinkedDriftoid Child, out int Index)
{
Index = 0;
Vector pos = this.Position;
double tarangle = (Child.Position - pos).Angle;
if (this._LinkedParent != null)
{
double lowangle = (this._LinkedParent.Position - pos).Angle;
foreach (LinkedDriftoid ld in this._LinkedChildren)
{
double highangle = (ld.Position - pos).Angle;
if (Vector.AngleBetween(tarangle, lowangle, highangle))
{
break;
}
lowangle = highangle;
Index++;
}
}
else
{
if (this._LinkedChildren.Count == 0)
{
Index = 0;
}
else
{
if (this._LinkedChildren.Count == 1)
{
Index = 1;
}
else
{
Index = 0;
double lowangle = (this._LinkedChildren[0].Position - pos).Angle;
for (int t = 1; t < this._LinkedChildren.Count; t++)
{
double highangle = (this._LinkedChildren[t].Position - pos).Angle;
if (Vector.AngleBetween(tarangle, lowangle, highangle))
{
break;
}
lowangle = highangle;
Index++;
}
}
}
}
return Child.AllowParentLink(this) && this.AllowLink(Index, this, Child);
}
/// <summary>
/// Called when a child is delinked from this driftoid.
/// </summary>
public virtual void OnChildDelink(LinkedDriftoid Child)
{
}
/// <summary>
/// Links a child driftoid to this driftoid.
/// </summary>
private void _Link(LinkedDriftoid Child, int Index)
{
// Make link
this._LinkedChildren.Add(null);
for (int t = this._LinkedChildren.Count - 1; t > Index; t--)
{
this._LinkedChildren[t] = this._LinkedChildren[t - 1];
}
this._LinkedChildren[Index] = Child;
Child._LinkedParent = this;
// Events
this.OnChildLink(Index, Child);
Child.OnParentLink(this);
}
/// <summary>
/// Gets if a player can control the links associated with the target.
/// </summary>
public bool HasLinkControl(Player Player, LinkedDriftoid Target)
{
LinkedDriftoid cur = Target;
while (cur != null)
{
NucleusDriftoid ndr = cur as NucleusDriftoid;
if (ndr != null)
{
if (ndr.Owner == Player)
{
return true;
}
}
cur = cur.LinkedParent;
}
return false;
}