// BiomeCache.cpp
// Implements the cBiomeCache class representing a biome source that caches data from the underlying biome source
#include "Globals.h"
#include "BiomeCache.h"
#include "Timer.h"
static int GetNumCores(void)
{
// Get number of cores by querying the system process affinity mask
DWORD Affinity, ProcAffinity;
GetProcessAffinityMask(GetCurrentProcess(), &ProcAffinity, &Affinity);
int NumCores = 0;
while (Affinity > 0)
{
if ((Affinity & 1) == 1)
{
NumCores++;
}
Affinity >>= 1;
} // while (Affinity > 0)
return NumCores;
}
cBiomeCache::cBiomeCache(void) :
m_Source(NULL),
m_BaseX(MAXINT),
m_BaseZ(MAXINT),
m_Available(NULL),
m_IsTerminatingThreads(false)
{
int NumThreads = GetNumCores();
NumThreads--; // One core should be left for the system to run on ;)
for (int i = NumThreads; i > 0; i--)
{
cThread * Thread = new cThread(*this);
m_Threads.push_back(Thread);
Thread->Start();
}
}
cBiomeCache::~cBiomeCache()
{
m_IsTerminatingThreads = true;
for (cThreads::iterator itr = m_Threads.begin(), end = m_Threads.end(); itr != end; ++itr)
{
m_evtQueued.Set();
}
for (cThreads::iterator itr = m_Threads.begin(), end = m_Threads.end(); itr != end; ++itr)
{
delete *itr;
}
m_Threads.clear();
SetSource(NULL);
}
cBiomeSource::eAvailability cBiomeCache::GetBiome(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_Biomes)
{
if (m_Source == NULL)
{
return baNever;
}
// Look up using the cache:
int x = a_ChunkX - m_BaseX;
int z = a_ChunkZ - m_BaseZ;
if ((x < 0) || (x >= m_Width) || (z < 0) || (z >= m_Height))
{
// Outside the cached region
return baNever;
}
cCSLock Lock(m_CS);
cItem * Item = m_Available[x + m_Width * z];
if (Item == NULL)
{
// Item hasn't been processed yet
return baLater;
}
if (Item->m_IsValid)
{
memcpy(a_Biomes, Item->m_Biomes, sizeof(a_Biomes));
return baNow;
}
// Item has been processed, but the underlying source refused to give the data to us
return baNever;
}
void cBiomeCache::HintViewArea(int a_MinChunkX, int a_MaxChunkX, int a_MinChunkZ, int a_MaxChunkZ)
{
cTimer Timer("Cache: HintViewArea");
if (
(a_MinChunkX == m_BaseX) &&
(a_MaxChunkX == m_BaseX + m_Width - 1) &&
(a_MinChunkZ == m_BaseZ) &&
(a_MaxChunkZ == m_BaseZ + m_Height - 1)
)
{
// The same set of parameters, bail out
return;
}
if (m_Source != NULL)
{
m_Source->HintViewArea(a_MinChunkX, a_MaxChunkX, a_MinChunkZ, a_MaxChunkZ);
}
int NewWidth = a_MaxChunkX - a_MinChunkX + 1;
int NewHeight = a_MaxChunkZ - a_MinChunkZ + 1;
// Make a new empty cache table:
pItem * NewAvailable = new pItem[NewWidth * NewHeight];
for (int i = NewWidth * NewHeight - 1; i >= 0; --i)
{
NewAvailable[i] = NULL;
}
// Move the common contents of the old table into the new table:
cCSLock Lock(m_CS);
for (int z = 0; z < NewHeight; z++)
{
int OldZ = z + a_MinChunkZ - m_BaseZ;
if ((OldZ < 0) || (OldZ >= m_Height))
{
continue;
}
for (int x = 0; x < NewWidth; x++)
{
int OldX = x + a_MinChunkX - m_BaseX;
if ((OldX < 0) || (OldX >= m_Width))
{
continue;
}
NewAvailable[x + NewWidth * z] = m_Available[OldX + m_Width * OldZ];
m_Available[OldX + m_Width * OldZ] = NULL;
} // for x
} // for z
// All items that aren't common go into the pool:
for (int idx = 0, z = 0; z < m_Height; z++)
{
for (int x = 0; x < m_Width; ++x, ++idx)
{
if (m_Available[idx] != NULL)
{
m_Pool.push_back(m_Available[idx]);
m_Available[idx] = NULL;
}
}
}
// Replace the cache table:
delete m_Available;
m_Available = NewAvailable;
m_Width = NewWidth;
m_Height = NewHeight;
m_BaseX = a_MinChunkX;
m_BaseZ = a_MinChunkZ;
// Remove all items outside the coords:
FilterOutItems(m_Queue, a_MinChunkX, a_MaxChunkX, a_MinChunkZ, a_MaxChunkZ);
// Queue all items from inside the coords into m_Queue:
for (int z = 0; z < NewHeight; z++)
{
for (int x = 0; x < NewWidth; x++)
{
if (m_Available[x + m_Width * z] != NULL)
{
// Already calculated, skip
continue;
}
if (m_Pool.empty())
{
m_Pool.push_back(new cItem(x + a_MinChunkX, z + a_MinChunkZ));
}
ASSERT(!m_Pool.empty());
m_Pool.back()->m_ChunkX = x + a_MinChunkX;
m_Pool.back()->m_ChunkZ = z + a_MinChunkZ;
m_Queue.push_back(m_Pool.back());
m_Pool.pop_back();
m_evtQueued.Set();
} // for x
} // for z
}
void cBiomeCache::SetSource(cBiomeSource * a_Source)
{
// TODO: Stop all threads, so that they don't use the source anymore!
delete m_Source;
m_Source = a_Source;
// Invalidate cache contents:
cCSLock Lock(m_CS);
m_BaseX = MAXINT;
m_BaseZ = MAXINT;
m_Pool.splice(m_Pool.end(), m_Queue);
}
void cBiomeCache::FilterOutItems(cItems & a_Items, int a_MinChunkX, int a_MaxChunkX, int a_MinChunkZ, int a_MaxChunkZ)
{
for (cItems::iterator itr = a_Items.begin(); itr != a_Items.end();)
{
if (
((*itr)->m_ChunkX < a_MinChunkX) ||
((*itr)->m_ChunkX > a_MaxChunkX) ||
((*itr)->m_ChunkX < a_MinChunkX) ||
((*itr)->m_ChunkX > a_MaxChunkX)
)
{
m_Pool.push_back(*itr);
itr = a_Items.erase(itr);
}
else
{
++itr;
}
}
}
void cBiomeCache::thrProcessQueueItem(void)
{
cItem * Item = NULL;
{
cCSLock Lock(m_CS);
if (m_Queue.empty())
{
cCSUnlock Unlock(Lock);
m_evtQueued.Wait();
}
if (m_IsTerminatingThreads || m_Queue.empty())
{
// We've been woken up only to die / spurious wakeup
return;
}
Item = m_Queue.back();
m_Queue.pop_back();
}
// Process the item:
Item->m_IsValid = (m_Source->GetBiome(Item->m_ChunkX, Item->m_ChunkZ, Item->m_Biomes) == baNow);
// Store result:
cCSLock Lock(m_CS);
int x = Item->m_ChunkX - m_BaseX;
int z = Item->m_ChunkZ - m_BaseZ;
if ((x < 0) || (x >= m_Width) || (z < 0) || (z >= m_Height))
{
// The cache rectangle has changed under our fingers, drop this chunk
return;
}
m_Available[x + m_Width * z] = Item;
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cBiomeCache::cItem:
cBiomeCache::cItem::cItem(int a_ChunkX, int a_ChunkZ) :
m_ChunkX(a_ChunkX),
m_ChunkZ(a_ChunkZ)
{
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cBiomeCache::cThread:
cBiomeCache::cThread::cThread(cBiomeCache & a_Parent) :
super("Biome cache thread"),
m_Parent(a_Parent)
{
}
void cBiomeCache::cThread::Execute(void)
{
while (!m_ShouldTerminate && !m_Parent.m_IsTerminatingThreads)
{
m_Parent.thrProcessQueueItem();
}
}
