/// <summary>
/// foamliu, 2009/01/20.
///
/// 目标可达且彼此不互斥.
/// </summary>
/// <returns></returns>
private bool GoalsReachable()
{
// 首先是所有目标中的命题都在.
foreach (string literal in this.m_goal.Literals)
{
if (!this.m_lastProp.Conjunction.Literals.Contains(literal))
{
return(false);
}
}
// 其次目标中的命题不彼此互斥.
for (int i = 0; i < m_goal.Literals.Count; i++)
{
Proposition theProp1 = m_lastProp.GetProposition(m_goal.Literals[i]);
for (int j = i + 1; j < m_goal.Literals.Count; j++)
{
Proposition theProp2 = m_lastProp.GetProposition(m_goal.Literals[j]);
if (theProp1.IsMutex(theProp2))
{
return(false);
}
}
}
return(true);
}
/// <summary>
/// foamliu, 2009/01/22.
///
/// 是否选中的 action 已经可以满足它.
/// </summary>
/// <returns></returns>
private bool SatisfiedBySelectedActions(Proposition theProp)
{
foreach (Action theAct in m_selectedActions)
{
if (theProp.AddEdges.Contains(theAct))
{
return(true);
}
}
return(false);
}
/// <summary>
/// foamliu, 2009/01/21, 建立 Del-Effects 边.
/// </summary>
private void CreateDelEdges(Action theAct)
{
Conjunction add = theAct.DelEffects;
foreach (string s in add.Literals)
{
Proposition theProp = m_next.AddProposition(s);
theProp.AddDelEdge(theAct);
theAct.AddDelProp(theProp);
}
}
/// <summary>
/// foamliu, 2009/01/21, 建立 PreCondition 边.
///
/// 例如:
/// Move ( b1, b2, b3 )
/// PreCondition 是:
/// ON (b1, b2) & Clear (b1) & Clear (b3)
/// </summary>
/// <param name="theAct"></param>
private void CreatePreEdges(Action theAct)
{
Conjunction pre = theAct.PreCondition;
foreach (string s in pre.Literals)
{
Proposition theProp = m_prev.GetProposition(s);
theProp.AddPreEdge(theAct);
theAct.AddPreProp(theProp);
}
}
public Proposition AddProposition(Proposition thePro)
{
// foamliu, 2009/01/22, fix a bug:
// {"An item with the same key has already been added."}.
if (m_dict.ContainsKey(thePro.Name))
{
return(m_dict[thePro.Name]);
}
m_props.Add(thePro);
m_dict.Add(thePro.Name, thePro);
m_conj.Literals.Add(thePro.Name);
return(thePro);
}
/// <summary>
/// foamliu, 2009/01/22, 检测命题互斥.
///
/// 要求所有相关的 action 都彼此互斥.
/// </summary>
/// <param name="theProp1"></param>
/// <param name="theProp2"></param>
/// <returns></returns>
private bool TestActions(Proposition theProp1, Proposition theProp2)
{
foreach (Action theAct1 in theProp1.AddEdges)
{
foreach (Action theAct2 in theProp2.AddEdges)
{
if (theAct1.IsMutex(theAct2) == false)
{
return(false);
}
}
}
return(true);
}
/// <summary>
/// foamliu, 2009/01/22, 检测互斥的命题.
///
/// 下面这段拷贝自如下论文的 2.2 节:
/// "Fast Planning Through Planning Graph Analysis"
/// Two propositions p and q in a proposition-level are marked as exclusive if all ways of
/// creating proposition p are exclusive of all ways of creating proposition q. Specifically, they
/// are marked as exclusive if each action a having an add-edge to proposition p is marked as
/// exclusive of each action b having an add-edge to proposition q.
/// </summary>
public void TestMutex()
{
for (int i = 0; i < m_props.Count; i++)
{
for (int j = i + 1; j < m_props.Count; j++)
{
Proposition theProp1 = m_props[i];
Proposition theProp2 = m_props[j];
if (TestActions(theProp1, theProp2))
{
theProp1.MutexProps.Add(theProp2);
theProp2.MutexProps.Add(theProp1);
}
}
}
}
/// <summary>
/// foamliu, 2009/01/21, 添加 No-op actions.
/// </summary>
private void AddNoops()
{
Conjunction conj = m_prev.Conjunction;
foreach (string s in conj.Literals)
{
// 创建 No-op action.
Action theAct = new Action("NOOP: " + s);
theAct.PreCondition.Literals.Add(s);
theAct.AddEffects.Literals.Add(s);
this.m_actions.Add(theAct);
// 把这个 no-op 加入当前行为层.
Proposition theProp = m_prev.GetProposition(s);
theProp.AddPreEdge(theAct);
theAct.AddPreProp(theProp);
// 把这个命题加入下个命题层.
theProp = m_next.AddProposition(s);
theProp.AddAddEdge(theAct);
theAct.AddAddProp(theProp);
}
}
public bool IsMutex(Proposition otherProp)
{
return(m_mutexProps.Contains(otherProp));
}
public void AddDelProp(Proposition prop)
{
this.m_delProps.Add(prop);
}
public void AddAddProp(Proposition prop)
{
this.m_addProps.Add(prop);
}
public void AddPreProp(Proposition prop)
{
this.m_preEdges.Add(prop);
}