stk-code_catmod/src/items/network_item_manager.cpp

565 lines
23 KiB
C++

//
// SuperTuxKart - a fun racing game with go-kart
// Copyright (C) 2018 Joerg Henrichs
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 3
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#include "items/network_item_manager.hpp"
#include "karts/abstract_kart.hpp"
#include "modes/world.hpp"
#include "network/network_config.hpp"
#include "network/network_string.hpp"
#include "network/protocols/game_protocol.hpp"
#include "network/rewind_manager.hpp"
#include "network/stk_host.hpp"
#include "network/stk_peer.hpp"
bool NetworkItemManager::m_network_item_debugging = false;
// ============================================================================
/** Creates a new instance of the item manager. This is done at startup
* of each race.
* We must save the item state first (so that it is restored first), otherwise
* state updates for a kart could be overwritten by e.g. simulating the item
* collection later (which resets bubblegum counter), so a rewinder uid of
* "I" which is less than "Kx" (kart rewinder with id x)
*/
NetworkItemManager::NetworkItemManager()
: Rewinder({RN_ITEM_MANAGER}), ItemManager()
{
m_confirmed_switch_ticks = -1;
m_last_confirmed_item_ticks.clear();
initServer();
} // NetworkItemManager
//-----------------------------------------------------------------------------
/** If this is a server, initializing the peers in game
*/
void NetworkItemManager::initServer()
{
if (NetworkConfig::get()->isServer())
{
auto peers = STKHost::get()->getPeers();
for (auto& p : peers)
{
if (!p->isValidated() || p->isWaitingForGame())
continue;
m_last_confirmed_item_ticks[p] = 0;
}
}
} // initServer
//-----------------------------------------------------------------------------
/** Destructor. Cleans up all items and meshes stored.
*/
NetworkItemManager::~NetworkItemManager()
{
for (ItemState* is : m_confirmed_state)
{
delete is;
}
} // ~NetworkItemManager
//-----------------------------------------------------------------------------
void NetworkItemManager::reset()
{
m_confirmed_switch_ticks = -1;
ItemManager::reset();
} // reset
//-----------------------------------------------------------------------------
/** Called when a kart collects an item. In network games only the server
* acts on this event.
* \param item The item that was collected.
* \param kart The kart that collected the item.
*/
void NetworkItemManager::collectedItem(ItemState *item, AbstractKart *kart)
{
if (m_network_item_debugging)
Log::info("NIM", "collectedItem at %d index %d type %d ttr %d",
World::getWorld()->getTicksSinceStart(),
item->getItemId(), item->getType(), item->getTicksTillReturn());
if(NetworkConfig::get()->isServer())
{
ItemManager::collectedItem(item, kart);
// The server saves the collected item as item event info
m_item_events.lock();
m_item_events.getData().emplace_back(World::getWorld()->getTicksSinceStart(),
item->getItemId(),
kart->getWorldKartId(),
item->getTicksTillReturn());
m_item_events.unlock();
}
else
{
// The client predicts item collection:
ItemManager::collectedItem(item, kart);
}
} // collectedItem
// ----------------------------------------------------------------------------
/** Called when a switch is activated. On the server adds this information to
* the item state so it can be sent to all clients.
*/
void NetworkItemManager::switchItems()
{
if (NetworkConfig::get()->isServer())
{
// The server saves the collected item as item event info
m_item_events.lock();
// Create a switch event - the constructor called determines
// the type of the event automatically.
m_item_events.getData()
.emplace_back(World::getWorld()->getTicksSinceStart());
m_item_events.unlock();
}
ItemManager::switchItems();
} // switchItems
// ----------------------------------------------------------------------------
/** Called when a new item is created, e.g. bubble gum.
* \param type Type of the item.
* \param kart In case of a dropped item used to avoid that a kart
* is affected by its own items.
* \param server_xyz In case of rewind the server's position of this item.
* \param server_normal In case of rewind the server's normal of this item.
*/
Item* NetworkItemManager::dropNewItem(ItemState::ItemType type,
const AbstractKart *kart,
const Vec3 *server_xyz,
const Vec3 *server_normal)
{
Item *item = ItemManager::dropNewItem(type, kart, server_xyz, server_normal);
if(!item) return NULL;
// Nothing else to do for client
if (NetworkConfig::get()->isClient()) return item;
assert(!server_xyz);
// Server: store the data for this event:
m_item_events.lock();
m_item_events.getData().emplace_back(World::getWorld()->getTicksSinceStart(),
type, item->getItemId(),
kart->getWorldKartId(),
item->getXYZ(),
item->getNormal());
m_item_events.unlock();
return item;
} // dropNewItem
// ----------------------------------------------------------------------------
/** Called by the GameProtocol when a confirmation for an item event is
* received by the server. Once all hosts have confirmed an event, it can be
* deleted and won't be sent to any clients again.
* \param peer Peer confirming the latest event time received.
* \param ticks Time at which the last event was received.
*/
void NetworkItemManager::setItemConfirmationTime(std::weak_ptr<STKPeer> peer,
int ticks)
{
assert(NetworkConfig::get()->isServer());
std::unique_lock<std::mutex> ul(m_live_players_mutex);
// Peer may get removed earlier if peer request to go back to lobby
if (m_last_confirmed_item_ticks.find(peer) !=
m_last_confirmed_item_ticks.end() &&
ticks > m_last_confirmed_item_ticks.at(peer))
m_last_confirmed_item_ticks.at(peer) = ticks;
// Now discard unneeded events and expired (disconnected) peer, i.e. all
// events that have been confirmed by all clients:
int min_time = std::numeric_limits<int32_t>::max();
for (auto it = m_last_confirmed_item_ticks.begin();
it != m_last_confirmed_item_ticks.end();)
{
if (it->first.expired())
{
it = m_last_confirmed_item_ticks.erase(it);
}
else
{
if (it->second < min_time) min_time = it->second;
it++;
}
}
ul.unlock();
// Find the last entry before the minimal confirmed time.
// Since the event list is sorted, all events up to this
// entry can be deleted.
m_item_events.lock();
auto p = m_item_events.getData().begin();
while (p != m_item_events.getData().end() && p->getTicks() < min_time)
p++;
m_item_events.getData().erase(m_item_events.getData().begin(), p);
m_item_events.unlock();
} // setItemConfirmationTime
//-----------------------------------------------------------------------------
/** Saves the state of all items. This is done by using a state that has
* been confirmed by all clients as a base, and then only adding any
* changes applied to that state later. As clients keep on confirming events
* the confirmed event will be moved forward in time, and older events can
* be deleted (and not sent to the clients anymore).
* This function is also called on the client in the first frame of a race
* to save the initial state, which is the first confirmed state by all
* clients.
*/
BareNetworkString* NetworkItemManager::saveState(std::vector<std::string>* ru)
{
ru->push_back(getUniqueIdentity());
// On the server:
// ==============
m_item_events.lock();
uint16_t n = (uint16_t)m_item_events.getData().size();
if(n==0)
{
BareNetworkString *s = new BareNetworkString();
m_item_events.unlock();
return s;
}
BareNetworkString *s =
new BareNetworkString(n * ( sizeof(int) + sizeof(uint16_t)
+ sizeof(uint8_t) ) );
for (auto p : m_item_events.getData())
{
p.saveState(s);
}
m_item_events.unlock();
return s;
} // saveState
//-----------------------------------------------------------------------------
/** Progresses the time for all item by the given number of ticks. Used
* when computing a new state from a confirmed state.
* \param ticks Number of ticks that need to be simulated.
*/
void NetworkItemManager::forwardTime(int ticks)
{
int new_ticks = World::getWorld()->getTicksSinceStart() + ticks;
World::getWorld()->setTicksForRewind(new_ticks);
for(auto &i : m_confirmed_state)
{
if (i) i->update(ticks);
} // for m_all_items
if(m_switch_ticks>ticks)
m_switch_ticks -= ticks;
else if (m_switch_ticks >= 0)
{
switchItemsInternal(m_confirmed_state);
m_switch_ticks = -1;
}
} // forwardTime
//-----------------------------------------------------------------------------
/** Restores the state of the items to the current world time. It takes the
* last saved confirmed state, applies any updates from the server, and
* then syncs up the confirmed state to the in-race items.
* It uses exactly 'count' bytes of the message.
* \param buffer the state content.
* \param count Number of bytes used for this state.
*/
void NetworkItemManager::restoreState(BareNetworkString *buffer, int count)
{
assert(NetworkConfig::get()->isClient());
// The state at World::getTicksSinceStart() needs to be restored. The
// confirmed state saved here was taken at m_confirmed_state_time
// (which is before getTicksSinceStart()). So first forward the confirmed
// state to the time we need to rewind to (i.e. getTicksSinceStart()).
// Then copy the new confirmed state to the current items. Any new
// items (dropped bubblegums) that have been predicted on a client
// and not been confirmed by the server data will be removed automatically
// at this stage. In more detail:
//
// 1) Apply all events included in this state to the confirmed state.
// It is possible that the server inludes events that have happened
// before the confirmed time on this client (the server keeps on
// sending all event updates till all clients have confirmed that
// that they have received them!!) - which will simply be ignored/
// This phase will only act on the confirmed ItemState in the
// NetworkItemManager, nothing in the ItemManager will be changed.
// a) When a collection event is found, adjust the confirmed item state
// only (this state will later be copied to the current items).
// It still call collected() in the item, which will update e.g.
// the previous owner, use up counter etc. for that item.
// b) When a new item is created, create an ItemState instance for
// this item, and put it in the confirmed state. Make sure the
// same index position is used.
// c) If a switch is used, this will be recorded in
// m_confirmed_switch_ticks.
//
// 2) Inform the server that those item events have been received.
// Once the server has received confirmation from all clients
// for events, they will not be resent anymore.
//
// 3) Once all new events have been applied to the confirmed state the
// time must be <= world time. Forward the confirmed state to
// world time (i.e. all confirmed items will get their ticksTillReturn
// value updated), and update m_confirmed_state_time to the world time.
//
// 4) Finally update the ItemManager state from the confirmed state:
// Any items that exist in both data structures will be updated.
// If an item exist in the ItemManager but not in the confirmed state
// of the NetworkItemManager, the item in the item manager will be
// delete - it was a predict item, which has not been confirmed by
// the server (e.g. a kart drops a bubble gum, and either the server
// has not received that event yet to confirm it, or perhaps the
// server detects that the kart did not even have a bubble gum).
// Similary, if an item is not in the confirmed state anymore,
// but in the ItemManager, it can mean that an item was collected
// on the server, which was not predicted. The item in the ItemManager
// will be deleted (if a kart has collected this item, the kart state
// will include the changed state information for the kart, so no need
// to update the kart for this).
//
// From here the replay can happen.
// 1) Apply all events to current confirmed state:
// -----------------------------------------------
World *world = World::getWorld();
// The world clock was set by the RewindManager to be the time
// of the state we are rewinding to. But the confirmed state of
// the network manager is before this (we are replaying item events
// since the last confirmed state in order to get a new confirmed state).
// So we need to reset the clock to the time of the confirmed state,
// and then forward this time accordingly. Getting the world time right
// during forwarding the item state is important since e.g. the bubble
// gum torque depends on the time. If the world time would be incorrect
// at the time the collection event happens, the torque would be
// predicted incorrectly, resulting in stuttering.
int current_time = m_confirmed_state_time;
// Reset the ItemManager's switch ticks to the value it had a the
// confirmed time:
m_switch_ticks = m_confirmed_switch_ticks;
int rewind_to_time = world->getTicksSinceStart(); // Save time we rewind to
world->setTicksForRewind(current_time);
bool has_state = count > 0;
// Note that the actual ItemManager states must NOT be changed here, only
// the confirmed states in the Network manager are allowed to be modified.
// They will all be copied to the ItemManager states after the loop.
while(count > 0)
{
// 1.1) Decode the event in the message
// ------------------------------------
ItemEventInfo iei(buffer, &count);
if(m_network_item_debugging)
Log::info("NIM", "Rewindto %d current %d iei.index %d iei tick %d iei.coll %d iei.new %d iei.ttr %d confirmed %lx",
rewind_to_time, current_time,
iei.getIndex(),
iei.getTicks(), iei.isItemCollection(), iei.isNewItem(),
iei.getTicksTillReturn(),
iei.getIndex() < (int)m_confirmed_state.size() && iei.getIndex() != -1 ?
m_confirmed_state[iei.getIndex()] : NULL);
// 1.2) If the event needs to be applied, forward
// the time to the time of this event:
// ----------------------------------------------
int dt = iei.getTicks() - current_time;
// Skip any events that are 'in the past' (i.e. have been sent again by
// the server because it has not yet received confirmation from all
// clients).
if(dt<0) continue;
// Forward the saved state:
if (dt>0) forwardTime(dt);
if(iei.isItemCollection())
{
int index = iei.getIndex();
// An item on the track was collected:
AbstractKart *kart = world->getKart(iei.getKartId());
assert(m_confirmed_state[index] != NULL);
m_confirmed_state[index]->collected(kart); // Collect item
// Reset till ticks return from state (required for eating banana with bomb)
int ttr = iei.getTicksTillReturn();
m_confirmed_state[index]->setTicksTillReturn(ttr);
if (m_confirmed_state[index]->isUsedUp())
{
delete m_confirmed_state[index];
m_confirmed_state[index] = NULL;
}
}
else if(iei.isNewItem())
{
AbstractKart *kart = world->getKart(iei.getKartId());
ItemState *is = new ItemState(iei.getNewItemType(), kart,
iei.getIndex() );
is->initItem(iei.getNewItemType(), iei.getXYZ(), iei.getNormal());
if (m_switch_ticks >= 0)
{
ItemState::ItemType new_type = m_switch_to[is->getType()];
is->switchTo(new_type);
}
// A new confirmed item must either be inserted at the end of all
// items, or in an existing unused entry.
if (m_confirmed_state.size() <= is->getItemId())
{
// In case that the server should send items in the wrong
// order, e.g. it sends an item for index n+2, then the item
// for index n -> we might need to add NULL item states
// into the state array to make sure the indices are correct.
while(m_confirmed_state.size()<is->getItemId())
m_confirmed_state.push_back(NULL);
m_confirmed_state.push_back(is);
}
else
{
// If the new item has an already existing index,
// the slot in the confirmed state array must be free
assert(m_confirmed_state[is->getItemId()] == NULL);
m_confirmed_state[is->getItemId()] = is;
}
}
else if(iei.isSwitch())
{
// Switch all confirmed items:
ItemManager::switchItemsInternal(m_confirmed_state);
}
else
{
Log::error("NetworkItemManager",
"Received unknown event type at %d",
iei.getTicks());
}
current_time = iei.getTicks();
} // while count >0
// 2. Update Server
// ================
// Inform the server which events have been received (if there has
// been any updates - no need to send messages if nothing has changed)
if (has_state)
{
if (auto gp = GameProtocol::lock())
gp->sendItemEventConfirmation(world->getTicksSinceStart());
}
// 3. Forward the confirmed item state to the world time
// =====================================================
int dt = rewind_to_time - current_time;
if(dt>0) forwardTime(dt);
// 4. Copy the confirmed state to the current item state
// ======================================================
// We need to test all items - and confirmed or all_items could
// be the larger group (confirmed: when a new item was dropped
// by a remote kart; all_items: if an item is predicted on
// the client, but not yet confirmed). So
size_t max_index = std::max(m_confirmed_state.size(),
m_all_items.size() );
m_all_items.resize(max_index, NULL);
for(unsigned int i=0; i<max_index; i++)
{
ItemState *item = m_all_items[i];
const ItemState *is = i < m_confirmed_state.size()
? m_confirmed_state[i] : NULL;
// For every *(ItemState*)item = *is, all deactivated ticks, item id
// ... will be copied from item state to item
if (is && item)
{
*(ItemState*)item = *is;
}
else if (is && !item)
{
// A new item was dropped according to the server that is not
// yet part of the current state --> create new item
Vec3 xyz = is->getXYZ();
Vec3 normal = is->getNormal();
Item *item_new = dropNewItem(is->getType(), is->getPreviousOwner(),
&xyz, &normal );
*((ItemState*)item_new) = *is;
m_all_items[i] = item_new;
insertItemInQuad(item_new);
}
else if (!is && item)
{
deleteItemInQuad(item);
delete item;
m_all_items[i] = NULL;
}
} // for i < max_index
// Clean up the rest
m_all_items.resize(m_confirmed_state.size());
// Now set the clock back to the 'rewindto' time:
world->setTicksForRewind(rewind_to_time);
// Save the current local time as confirmed time
m_confirmed_state_time = world->getTicksSinceStart();
m_confirmed_switch_ticks = m_switch_ticks;
} // restoreState
//-----------------------------------------------------------------------------
/** Save all current items at current ticks in server for live join
*/
void NetworkItemManager::saveCompleteState(BareNetworkString* buffer) const
{
const uint32_t all_items = (uint32_t)m_all_items.size();
buffer->addUInt32(World::getWorld()->getTicksSinceStart())
.addUInt32(m_switch_ticks).addUInt32(all_items);
for (unsigned i = 0; i < all_items; i++)
{
if (m_all_items[i])
{
buffer->addUInt8(1);
m_all_items[i]->saveCompleteState(buffer);
}
else
buffer->addUInt8(0);
}
} // saveCompleteState
//-----------------------------------------------------------------------------
/** Restore all current items at current ticks in client for live join
* or at the start of a race.
*/
void NetworkItemManager::restoreCompleteState(const BareNetworkString& buffer)
{
m_confirmed_state_time = buffer.getUInt32();
m_confirmed_switch_ticks = buffer.getUInt32();
uint32_t all_items = buffer.getUInt32();
for (ItemState* is : m_confirmed_state)
{
delete is;
}
m_confirmed_state.clear();
for (unsigned i = 0; i < all_items; i++)
{
const bool has_item = buffer.getUInt8() == 1;
if (has_item)
{
ItemState* is = new ItemState(buffer);
m_confirmed_state.push_back(is);
}
else
m_confirmed_state.push_back(NULL);
}
} // restoreCompleteState