Further improvements on redstone speed

Based on suggestions of @worktycho
* Repeaters now walk their data structure only when needed
* Fixed a bug with cChunkData returning an incorrect value for whether a
meta had changed

src/ChunkData.cpp

@@ -258,7 +258,7 @@ bool cChunkData::SetMeta(int a_RelX, int a_RelY, int a_RelZ, NIBBLETYPE a_Nibble
 		(m_Sections[Section]->m_BlockMetas[Index / 2] & (0xf0 >> ((Index & 1) * 4))) |  // The untouched nibble
 		((a_Nibble & 0x0f) << ((Index & 1) * 4))  // The nibble being set
 	);
-	return oldval == a_Nibble;
+	return oldval != a_Nibble;
 }
 
 

src/Simulator/IncrementalRedstoneSimulator.cpp

@@ -266,19 +266,20 @@ void cIncrementalRedstoneSimulator::SimulateChunk(float a_Dt, int a_ChunkX, int
 			case E_BLOCK_REDSTONE_REPEATER_OFF:
 			case E_BLOCK_REDSTONE_REPEATER_ON:
 			{
-				if (ShouldUpdateSimulateOnceBlocks)
+				bool FoundItem = false;
-				{
+				for (RepeatersDelayList::iterator repeateritr = m_RepeatersDelayList->begin(); repeateritr != m_RepeatersDelayList->end(); ++repeateritr)
-					HandleRedstoneRepeater(dataitr->x, dataitr->y, dataitr->z, dataitr->Data);
-					break;
-				}
-				for (RepeatersDelayList::const_iterator repeateritr = m_RepeatersDelayList->begin(); repeateritr != m_RepeatersDelayList->end(); ++repeateritr)
 				{
 					if (repeateritr->a_RelBlockPos == Vector3i(dataitr->x, dataitr->y, dataitr->z))
 					{
-						HandleRedstoneRepeater(dataitr->x, dataitr->y, dataitr->z, dataitr->Data);
+						HandleRedstoneRepeater(dataitr->x, dataitr->y, dataitr->z, dataitr->Data, repeateritr);
+						FoundItem = true;
 						break;
 					}
 				}
+				if (!FoundItem && ShouldUpdateSimulateOnceBlocks)
+				{
+					HandleRedstoneRepeater(dataitr->x, dataitr->y, dataitr->z, dataitr->Data, m_RepeatersDelayList->end());
+				}
 				break;
 			}
 			case E_BLOCK_WOODEN_PRESSURE_PLATE:
@@ -746,7 +747,7 @@ void cIncrementalRedstoneSimulator::HandleRedstoneWire(int a_RelBlockX, int a_Re
 
 
 
-void cIncrementalRedstoneSimulator::HandleRedstoneRepeater(int a_RelBlockX, int a_RelBlockY, int a_RelBlockZ, BLOCKTYPE a_MyState)
+void cIncrementalRedstoneSimulator::HandleRedstoneRepeater(int a_RelBlockX, int a_RelBlockY, int a_RelBlockZ, BLOCKTYPE a_MyState, RepeatersDelayList::iterator a_Itr)
 {
 	/* Repeater Orientation Mini Guide:
 	===================================
@@ -773,29 +774,42 @@ void cIncrementalRedstoneSimulator::HandleRedstoneRepeater(int a_RelBlockX, int
 	NIBBLETYPE a_Meta = m_Chunk->GetMeta(a_RelBlockX, a_RelBlockY, a_RelBlockZ);
 	bool IsOn = (a_MyState == E_BLOCK_REDSTONE_REPEATER_ON);
     
+	bool WereItrsChanged = false;
 	if (!IsRepeaterLocked(a_RelBlockX, a_RelBlockY, a_RelBlockZ, a_Meta)) // If we're locked, change nothing. Otherwise:
 	{
 		bool IsSelfPowered = IsRepeaterPowered(a_RelBlockX, a_RelBlockY, a_RelBlockZ, a_Meta);
 		if (IsSelfPowered && !IsOn) // Queue a power change if powered, but not on and not locked.
 		{
-			QueueRepeaterPowerChange(a_RelBlockX, a_RelBlockY, a_RelBlockZ, a_Meta, true);
+			WereItrsChanged = QueueRepeaterPowerChange(a_RelBlockX, a_RelBlockY, a_RelBlockZ, a_Meta, true);
 		}
 		else if (!IsSelfPowered && IsOn) // Queue a power change if unpowered, on, and not locked.
 		{
-			QueueRepeaterPowerChange(a_RelBlockX, a_RelBlockY, a_RelBlockZ, a_Meta, false);
+			WereItrsChanged = QueueRepeaterPowerChange(a_RelBlockX, a_RelBlockY, a_RelBlockZ, a_Meta, false);
+		}
+		else
+		{
+			return;
+		}
+	}
+	else
+	{
+		return;
+	}
+
+	if (WereItrsChanged)
+	{
+		for (a_Itr = m_RepeatersDelayList->begin(); a_Itr != m_RepeatersDelayList->end(); ++a_Itr)
+		{
+			if (a_Itr->a_RelBlockPos == Vector3i(a_RelBlockX, a_RelBlockY, a_RelBlockZ))
+			{
+				break;
+			}
 		}
 	}
 
-	for (RepeatersDelayList::iterator itr = m_RepeatersDelayList->begin(); itr != m_RepeatersDelayList->end(); ++itr)
+	if (a_Itr->a_ElapsedTicks >= a_Itr->a_DelayTicks) // Has the elapsed ticks reached the target ticks?
 	{
-		if (!itr->a_RelBlockPos.Equals(Vector3i(a_RelBlockX, a_RelBlockY, a_RelBlockZ)))
+		if (a_Itr->ShouldPowerOn)
-		{
-			continue;
-		}
-
-		if (itr->a_ElapsedTicks >= itr->a_DelayTicks) // Has the elapsed ticks reached the target ticks?
-		{
-			if (itr->ShouldPowerOn)
 		{
 			if (!IsOn)
 			{
@@ -840,7 +854,7 @@ void cIncrementalRedstoneSimulator::HandleRedstoneRepeater(int a_RelBlockX, int
 			{
 				m_Chunk->SetBlock(a_RelBlockX, a_RelBlockY, a_RelBlockZ, E_BLOCK_REDSTONE_REPEATER_OFF, a_Meta);
 			}
-				m_RepeatersDelayList->erase(itr); // We can remove off repeaters which don't need further updating
+			m_RepeatersDelayList->erase(a_Itr); // We can remove off repeaters which don't need further updating
 			return;
 		}
 	}
@@ -849,9 +863,8 @@ void cIncrementalRedstoneSimulator::HandleRedstoneRepeater(int a_RelBlockX, int
 		// Apparently, incrementing ticks only works reliably here, and not in SimChunk;
 		// With a world with lots of redstone, the repeaters simply do not delay
 		// I am confounded to say why. Perhaps optimisation failure.
-			LOGD("Incremented a repeater @ {%i %i %i} | Elapsed ticks: %i | Target delay: %i", itr->a_RelBlockPos.x, itr->a_RelBlockPos.y, itr->a_RelBlockPos.z, itr->a_ElapsedTicks, itr->a_DelayTicks);
+		LOGD("Incremented a repeater @ {%i %i %i} | Elapsed ticks: %i | Target delay: %i", a_Itr->a_RelBlockPos.x, a_Itr->a_RelBlockPos.y, a_Itr->a_RelBlockPos.z, a_Itr->a_ElapsedTicks, a_Itr->a_DelayTicks);
-			itr->a_ElapsedTicks++;
+		a_Itr->a_ElapsedTicks++;
-		}
 	}
 }
 
@@ -1914,7 +1927,7 @@ void cIncrementalRedstoneSimulator::SetPlayerToggleableBlockAsSimulated(int a_Re
 
 
 
-void cIncrementalRedstoneSimulator::QueueRepeaterPowerChange(int a_RelBlockX, int a_RelBlockY, int a_RelBlockZ, NIBBLETYPE a_Meta, bool ShouldPowerOn)
+bool cIncrementalRedstoneSimulator::QueueRepeaterPowerChange(int a_RelBlockX, int a_RelBlockY, int a_RelBlockZ, NIBBLETYPE a_Meta, bool ShouldPowerOn)
 {
 	for (RepeatersDelayList::iterator itr = m_RepeatersDelayList->begin(); itr != m_RepeatersDelayList->end(); ++itr)
 	{
@@ -1922,14 +1935,14 @@ void cIncrementalRedstoneSimulator::QueueRepeaterPowerChange(int a_RelBlockX, in
 		{
 			if (ShouldPowerOn == itr->ShouldPowerOn) // We are queued already for the same thing, don't replace entry
 			{
-				return;
+				return false;
 			}
 
 			// Already in here (normal to allow repeater to continue on powering and updating blocks in front) - just update info and quit
 			itr->a_DelayTicks = (((a_Meta & 0xC) >> 0x2) + 1) * 2; // See below for description
 			itr->a_ElapsedTicks = 0;
 			itr->ShouldPowerOn = ShouldPowerOn;
-			return;
+			return false;
 		}
 	}
 
@@ -1944,7 +1957,7 @@ void cIncrementalRedstoneSimulator::QueueRepeaterPowerChange(int a_RelBlockX, in
 	RC.a_ElapsedTicks = 0;
 	RC.ShouldPowerOn = ShouldPowerOn;
 	m_RepeatersDelayList->push_back(RC);
-	return;
+	return true;
 }
 
 

src/Simulator/IncrementalRedstoneSimulator.h

@@ -108,7 +108,7 @@ private:
 	/** Handles redstone wire */
 	void HandleRedstoneWire(int a_RelBlockX, int a_RelBlockY, int a_RelBlockZ);
 	/** Handles repeaters */
-	void HandleRedstoneRepeater(int a_RelBlockX, int a_RelBlockY, int a_RelBlockZ, BLOCKTYPE a_MyState);
+	void HandleRedstoneRepeater(int a_RelBlockX, int a_RelBlockY, int a_RelBlockZ, BLOCKTYPE a_MyState, RepeatersDelayList::iterator a_Itr);
 	/* ====================== */
 
 	/* ====== DEVICES ====== */
@@ -145,8 +145,8 @@ private:
 	void SetDirectionLinkedPowered(int a_RelBlockX, int a_RelBlockY, int a_RelBlockZ, char a_Direction, unsigned char a_PowerLevel = MAX_POWER_LEVEL);
 	/** Marks all blocks immediately surrounding a coordinate as powered */
 	void SetAllDirsAsPowered(int a_RelBlockX, int a_RelBlockY, int a_RelBlockZ, unsigned char a_PowerLevel = MAX_POWER_LEVEL);
-	/** Queues a repeater to be powered or unpowered */
+	/** Queues a repeater to be powered or unpowered and returns if the m_RepeatersDelayList iterators were invalidated */
-	void QueueRepeaterPowerChange(int a_RelBlockX, int a_RelBlockY, int a_RelBlockZ, NIBBLETYPE a_Meta, bool ShouldPowerOn);
+	bool QueueRepeaterPowerChange(int a_RelBlockX, int a_RelBlockY, int a_RelBlockZ, NIBBLETYPE a_Meta, bool ShouldPowerOn);
 
 	/** Returns if a coordinate is powered or linked powered */
 	bool AreCoordsPowered(int a_RelBlockX, int a_RelBlockY, int a_RelBlockZ) { return AreCoordsDirectlyPowered(a_RelBlockX, a_RelBlockY, a_RelBlockZ) || AreCoordsLinkedPowered(a_RelBlockX, a_RelBlockY, a_RelBlockZ); }