// construct a save point
public ModelUndo(Agent agent)
{
m_age = agent.age();
m_hash = agent.hash();
m_reward = agent.reward();
m_history_size = agent.historySize();
m_last_update_percept = agent.m_last_update_percept;
}
/* update the non-context tree part of an internal agent after receiving a percept */
public void nonCTModelUpdate(symbol_list_t percept)
{
if (m_use_self_model)
{
m_self_model.updateHistory(percept);
}
m_hash = hashAfterSymbols(percept);
m_total_reward += rewardFromPercept(percept);
m_last_update_percept = true;
}
// resets the agent
public void reset()
{
m_ct.clear();
if (m_use_self_model)
{
m_self_model.clear();
}
m_time_cycle = 0;
m_total_reward = 0.0;
m_last_update_percept = false;
m_hash = 5381 << 32;
}
// revert the agent's internal model of the world
// to that of a previous time cycle, false on failure
public bool modelRevert(ModelUndo mu)
{
// return false; // TODONE: implement
// assert(m_ct->historySize() > mu.historySize());
// assert(!m_use_self_model || m_self_model->historySize() > mu.historySize());
if (m_time_cycle < mu.age())
{
return(false);
}
// agent properties must be reverted before context update,
// since the predicates that depend on the context may
// depend on them
m_time_cycle = mu.age();
m_hash = mu.hash();
m_total_reward = mu.reward();
m_last_update_percept = mu.lastUpdatePercept();
// revert the context tree and history back to it's previous state
if (mu.lastUpdatePercept())
{ // if we are undoing an action
m_ct.revertHistory(mu.historySize());
if (m_use_self_model)
{
Int64 end_size = (Int64)m_self_model.historySize();
for (Int64 i = 0; i < (Int64)end_size - (Int64)mu.historySize(); i++)
{
m_self_model.revert();
}
}
}
else
{
// if we are undoing an observation / reward
Int64 end_size = (Int64)m_ct.historySize();
Int64 percept_bits = (Int64)(m_obs_bits + m_rew_bits);
Int64 lim = (Int64)end_size - (Int64)mu.historySize();
for (Int64 i = 0; i < (Int64)end_size - (Int64)mu.historySize(); i++)
{
//ORIGINAL :: m_ct.revert(percept_bits - i - 1);
Int64 offset = percept_bits - i - 1;
m_ct.revert();
for (Int64 ix = 0; ix < (Int64)m_ct.size(); ix++)
{
if (ix != offset)
{
m_ct.m_history.pop_back();
}
}
}
if (m_use_self_model)
{
m_self_model.revertHistory(mu.historySize());
}
}
//assert(!m_use_self_model || m_self_model.historySize() == m_ct.historySize());
return(true);
}
