cuberite-2a/src/Entities/Minecart.cpp

// Minecart.cpp

// Implements the cMinecart class representing a minecart in the world
// Handles physics when a minecart is on any type of rail (overrides simulator in Entity.cpp)
// Indiana Jones!

#include "Globals.h"
#include "Minecart.h"
#include "../World.h"
#include "../ClientHandle.h"
#include "../Chunk.h"
#include "Player.h"
#include "../BoundingBox.h"

#define MAX_SPEED 8
#define MAX_SPEED_NEGATIVE -MAX_SPEED





cMinecart::cMinecart(ePayload a_Payload, double a_X, double a_Y, double a_Z) :
	super(etMinecart, a_X, a_Y, a_Z, 0.98, 0.7),
	m_Payload(a_Payload),
	m_LastDamage(0),
	m_DetectorRailPosition(0, 0, 0),
	m_bIsOnDetectorRail(false)
{
	SetMass(20.f);
	SetMaxHealth(6);
	SetHealth(6);
	SetWidth(1.2);
	SetHeight(0.9);
}




void cMinecart::SpawnOn(cClientHandle & a_ClientHandle)
{
	char SubType = 0;
	switch (m_Payload)
	{
		case mpNone:    SubType = 0; break;
		case mpChest:   SubType = 1; break;
		case mpFurnace: SubType = 2; break;
		case mpTNT:     SubType = 3; break;
		case mpHopper:  SubType = 5; break;
		default:
		{
			ASSERT(!"Unknown payload, cannot spawn on client");
			return;
		}
	}
	a_ClientHandle.SendSpawnVehicle(*this, 10, SubType); // 10 = Minecarts, SubType = What type of Minecart
}





void cMinecart::HandlePhysics(float a_Dt, cChunk & a_Chunk)
{
	if (IsDestroyed()) // Mainly to stop detector rails triggering again after minecart is dead
	{
		return;
	}

	int PosY = (int)floor(GetPosY());
	if ((PosY <= 0) || (PosY >= cChunkDef::Height))
	{
		// Outside the world, just process normal falling physics
		super::HandlePhysics(a_Dt, a_Chunk);
		BroadcastMovementUpdate();
		return;
	}
	
	int RelPosX = (int)floor(GetPosX()) - a_Chunk.GetPosX() * cChunkDef::Width;
	int RelPosZ = (int)floor(GetPosZ()) - a_Chunk.GetPosZ() * cChunkDef::Width;
	cChunk * Chunk = a_Chunk.GetRelNeighborChunkAdjustCoords(RelPosX, RelPosZ);
	if (Chunk == NULL)
	{
		// Inside an unloaded chunk, bail out all processing
		return;
	}

	BLOCKTYPE InsideType;
	NIBBLETYPE InsideMeta;
	Chunk->GetBlockTypeMeta(RelPosX, PosY, RelPosZ, InsideType, InsideMeta);

	if (!IsBlockRail(InsideType))
	{
		Chunk->GetBlockTypeMeta(RelPosX, PosY + 1, RelPosZ, InsideType, InsideMeta); // When an descending minecart hits a flat rail, it goes through the ground; check for this
		if (IsBlockRail(InsideType)) AddPosY(1); // Push cart upwards
	}

	if (IsBlockRail(InsideType))
	{
		bool WasDetectorRail = false;
		SnapToRail(InsideMeta);

		switch (InsideType)
		{
			case E_BLOCK_RAIL: HandleRailPhysics(InsideMeta, a_Dt); break;
			case E_BLOCK_ACTIVATOR_RAIL: break;
			case E_BLOCK_POWERED_RAIL: HandlePoweredRailPhysics(InsideMeta); break;
			case E_BLOCK_DETECTOR_RAIL:
			{
				HandleDetectorRailPhysics(InsideMeta, a_Dt);
				WasDetectorRail = true;
				break;
			}
			default: VERIFY(!"Unhandled rail type despite checking if block was rail!"); break;
		}

		AddPosition(GetSpeed() * (a_Dt / 1000)); // Commit changes; as we use our own engine when on rails, this needs to be done, whereas it is normally in Entity.cpp

		if (m_bIsOnDetectorRail && !WasDetectorRail)
		{
			m_World->SetBlock(m_DetectorRailPosition.x, m_DetectorRailPosition.y, m_DetectorRailPosition.z, E_BLOCK_DETECTOR_RAIL, m_World->GetBlockMeta(m_DetectorRailPosition) & 0x07);
			m_bIsOnDetectorRail = false;
		}
	}
	else
	{
		// Not on rail, default physics
		SetPosY(floor(GetPosY()) + 0.35); // HandlePhysics overrides this if minecart can fall, else, it is to stop ground clipping minecart bottom when off-rail
		super::HandlePhysics(a_Dt, *Chunk);
	}
	
	// Broadcast positioning changes to client
	BroadcastMovementUpdate();
}





void cMinecart::HandleRailPhysics(NIBBLETYPE a_RailMeta, float a_Dt)
{
	/*
	NOTE: Please bear in mind that taking away from negatives make them even more negative,
	adding to negatives make them positive, etc.
	*/
	
	switch (a_RailMeta)
	{
		case E_META_RAIL_ZM_ZP: // NORTHSOUTH
		{
			SetRotation(270);
			SetPosY(floor(GetPosY()) + 0.55);
			SetSpeedY(0); // Don't move vertically as on ground
			SetSpeedX(0); // Correct diagonal movement from curved rails

			if (TestBlockCollision(a_RailMeta)) return;
			
			if (GetSpeedZ() != 0) // Don't do anything if cart is stationary
			{
				if (GetSpeedZ() > 0)
				{
					// Going SOUTH, slow down
					AddSpeedZ(-0.1);
				}
				else
				{
					// Going NORTH, slow down
					AddSpeedZ(0.1);
				}
			}
			break;
		}
		case E_META_RAIL_XM_XP: // EASTWEST
		{
			SetRotation(180);
			SetPosY(floor(GetPosY()) + 0.55);
			SetSpeedY(0);
			SetSpeedZ(0);

			if (TestBlockCollision(a_RailMeta)) return;

			if (GetSpeedX() != 0)
			{
				if (GetSpeedX() > 0)
				{
					AddSpeedX(-0.1);
				}
				else
				{
					AddSpeedX(0.1);
				}
			}
			break;
		}
		case E_META_RAIL_ASCEND_ZM: // ASCEND NORTH
		{
			SetRotation(270);
			SetSpeedX(0);

			if (GetSpeedZ() >= 0)
			{
				// SpeedZ POSITIVE, going SOUTH
				if (GetSpeedZ() <= MAX_SPEED) // Speed limit
				{
					AddSpeedZ(0.5); // Speed up
					SetSpeedY(-GetSpeedZ()); // Downward movement is negative (0 minus positive numbers is negative)
				}
			}
			else
			{
				// SpeedZ NEGATIVE, going NORTH
				AddSpeedZ(1); // Slow down
				SetSpeedY(-GetSpeedZ()); // Upward movement is positive (0 minus negative number is positive number)
			}
			break;
		}
		case E_META_RAIL_ASCEND_ZP: // ASCEND SOUTH
		{
			SetRotation(270);
			SetSpeedX(0);

			if (GetSpeedZ() > 0)
			{
				// SpeedZ POSITIVE, going SOUTH
				AddSpeedZ(-1); // Slow down
				SetSpeedY(GetSpeedZ()); // Upward movement positive
			}
			else
			{
				if (GetSpeedZ() >= MAX_SPEED_NEGATIVE) // Speed limit
				{
					// SpeedZ NEGATIVE, going NORTH
					AddSpeedZ(-0.5); // Speed up
					SetSpeedY(GetSpeedZ()); // Downward movement negative
				}
			}
			break;
		}
		case E_META_RAIL_ASCEND_XM: // ASCEND EAST
		{
			SetRotation(180);
			SetSpeedZ(0);

			if (GetSpeedX() >= 0)
			{
				if (GetSpeedX() <= MAX_SPEED)
				{
					AddSpeedX(0.5);
					SetSpeedY(-GetSpeedX());
				}
			}
			else
			{
				AddSpeedX(1);
				SetSpeedY(-GetSpeedX());
			}
			break;
		}
		case E_META_RAIL_ASCEND_XP: // ASCEND WEST
		{
			SetRotation(180);
			SetSpeedZ(0);

			if (GetSpeedX() > 0)
			{
				AddSpeedX(-1);
				SetSpeedY(GetSpeedX());
			}
			else
			{
				if (GetSpeedX() >= MAX_SPEED_NEGATIVE)
				{
					AddSpeedX(-0.5);
					SetSpeedY(GetSpeedX());
				}
			}
			break;
		}
		case E_META_RAIL_CURVED_ZM_XM: // Ends pointing NORTH and WEST
		{
			SetRotation(315); // Set correct rotation server side
			SetPosY(floor(GetPosY()) + 0.55); // Levitate dat cart

			if (TestBlockCollision(a_RailMeta)) return;

			if (GetSpeedZ() > 0) // Cart moving south
			{
				int OldX = (int)floor(GetPosX());
				AddSpeedX(-GetSpeedZ() + 0.5); // See below
				AddPosX(-GetSpeedZ() * (a_Dt / 1000)); // Diagonally move southwest (which will make cart hit a southwest rail)
				// If we are already at southwest rail, set Z speed to zero as we can be moving so fast, MCS doesn't tick fast enough to active the handle for the rail...
				// ...and so we derail unexpectedly.
				if (GetPosX() <= OldX - 1) SetSpeedZ(0);
			}
			else if (GetSpeedX() > 0) // Cart moving east
			{
				int OldZ = (int)floor(GetPosZ());
				AddSpeedZ(-GetSpeedX() + 0.5);
				AddPosZ(-GetSpeedX() * (a_Dt / 1000)); // Diagonally move northeast
				if (GetPosZ() <= OldZ - 1) SetSpeedX(0);
			}
			break;
		}
		case E_META_RAIL_CURVED_ZM_XP: // Curved NORTH EAST
		{
			SetRotation(225);
			SetPosY(floor(GetPosY()) + 0.55);

			if (TestBlockCollision(a_RailMeta)) return;

			if (GetSpeedZ() > 0)
			{
				int OldX = (int)floor(GetPosX());
				AddSpeedX(GetSpeedZ() - 0.5);
				AddPosX(GetSpeedZ() * (a_Dt / 1000));
				if (GetPosX() >= OldX + 1) SetSpeedZ(0);
			}
			else if (GetSpeedX() < 0)
			{
				int OldZ = (int)floor(GetPosZ());
				AddSpeedZ(GetSpeedX() + 0.5);
				AddPosZ(GetSpeedX() * (a_Dt / 1000));
				if (GetPosZ() <= OldZ - 1) SetSpeedX(0);
			}
			break;
		}
		case E_META_RAIL_CURVED_ZP_XM: // Curved SOUTH WEST
		{
			SetRotation(135);
			SetPosY(floor(GetPosY()) + 0.55);

			if (TestBlockCollision(a_RailMeta)) return;

			if (GetSpeedZ() < 0)
			{
				int OldX = (int)floor(GetPosX());
				AddSpeedX(GetSpeedZ() + 0.5);
				AddPosX(GetSpeedZ() * (a_Dt / 1000));
				if (GetPosX() <= OldX - 1) SetSpeedZ(0);
			}
			else if (GetSpeedX() > 0)
			{
				int OldZ = (int)floor(GetPosZ());
				AddSpeedZ(GetSpeedX() - 0.5);
				AddPosZ(GetSpeedX() * (a_Dt / 1000));
				if (GetPosZ() >= OldZ + 1) SetSpeedX(0);
			}
			break;
		}
		case E_META_RAIL_CURVED_ZP_XP: // Curved SOUTH EAST
		{
			SetRotation(45);
			SetPosY(floor(GetPosY()) + 0.55);

			if (TestBlockCollision(a_RailMeta)) return;

			if (GetSpeedZ() < 0)
			{
				int OldX = (int)floor(GetPosX());
				AddSpeedX(-GetSpeedZ() - 0.5);
				AddPosX(-GetSpeedZ() * (a_Dt / 1000));
				if (GetPosX() >= OldX + 1) SetSpeedZ(0);
			}
			else if (GetSpeedX() < 0)
			{
				int OldZ = (int)floor(GetPosZ());
				AddSpeedZ(-GetSpeedX() - 0.5);
				AddPosZ(-GetSpeedX() * (a_Dt / 1000));
				if (GetPosZ() >= OldZ + 1) SetSpeedX(0);
			}
			break;
		}
		default:
		{
			ASSERT(!"Unhandled rail meta!"); // Dun dun DUN!
			break;
		}
	}
}




void cMinecart::HandlePoweredRailPhysics(NIBBLETYPE a_RailMeta)
{
	// Initialise to 'slow down' values
	int AccelDecelSpeed = -1;
	int AccelDecelNegSpeed = 1;

	if ((a_RailMeta & 0x8) == 0x8)
	{
		// Rail powered - set variables to 'speed up' values
		AccelDecelSpeed = 1;
		AccelDecelNegSpeed = -1;
	}

	switch (a_RailMeta & 0x07)
	{
		case E_META_RAIL_ZM_ZP: // NORTHSOUTH
		{
			SetRotation(270);
			SetPosY(floor(GetPosY()) + 0.55);
			SetSpeedY(0);
			SetSpeedX(0);

			if (TestBlockCollision(a_RailMeta)) return;
			
			if (GetSpeedZ() != 0)
			{
				if (GetSpeedZ() > 0)
				{
					AddSpeedZ(AccelDecelNegSpeed);
				}
				else
				{
					AddSpeedZ(AccelDecelSpeed);
				}
			}
			break;
		}
		case E_META_RAIL_XM_XP: // EASTWEST
		{
			SetRotation(180);
			SetPosY(floor(GetPosY()) + 0.55);
			SetSpeedY(0);
			SetSpeedZ(0);

			if (TestBlockCollision(a_RailMeta)) return;

			if (GetSpeedX() != 0)
			{
				if (GetSpeedX() > 0)
				{
					AddSpeedX(AccelDecelSpeed);
				}
				else
				{
					AddSpeedX(AccelDecelNegSpeed);
				}
			}
			break;
		}
	}
}





void cMinecart::HandleDetectorRailPhysics(NIBBLETYPE a_RailMeta, float a_Dt)
{
	m_bIsOnDetectorRail = true;
	m_DetectorRailPosition = Vector3i((int)floor(GetPosX()), (int)floor(GetPosY()), (int)floor(GetPosZ()));

	m_World->SetBlockMeta(m_DetectorRailPosition, a_RailMeta | 0x08);

	HandleRailPhysics(a_RailMeta & 0x07, a_Dt);
}





void cMinecart::SnapToRail(NIBBLETYPE a_RailMeta)
{
	switch (a_RailMeta)
	{
		case E_META_RAIL_ASCEND_XM:
		case E_META_RAIL_ASCEND_XP:
		case E_META_RAIL_XM_XP:
		{
			SetSpeedZ(0);
			SetPosZ(floor(GetPosZ()) + 0.5);
			break;
		}
		case E_META_RAIL_ASCEND_ZM:
		case E_META_RAIL_ASCEND_ZP:
		case E_META_RAIL_ZM_ZP:
		{
			SetSpeedX(0);
			SetPosX(floor(GetPosX()) + 0.5);
			break;
		}
		default: break;
	}
}





bool cMinecart::TestBlockCollision(NIBBLETYPE a_RailMeta)
{
	switch (a_RailMeta)
	{
		case E_META_RAIL_ZM_ZP:
		{
			if (GetSpeedZ() > 0)
			{
				BLOCKTYPE Block = m_World->GetBlock((int)floor(GetPosX()), (int)floor(GetPosY()), (int)ceil(GetPosZ()));
				if (!IsBlockRail(Block) && g_BlockIsSolid[Block])
				{
					// We could try to detect a block in front based purely on coordinates, but xoft made a bounding box system - why not use? :P
					cBoundingBox bbBlock(Vector3d((int)floor(GetPosX()), (int)floor(GetPosY()), (int)ceil(GetPosZ())), 0.5, 1);
					cBoundingBox bbMinecart(Vector3d(GetPosX(), floor(GetPosY()), GetPosZ()), GetWidth() / 2, GetHeight());

					if (bbBlock.DoesIntersect(bbMinecart))
					{
						SetSpeed(0, 0, 0);
						SetPosZ(floor(GetPosZ()) + 0.4);
						return true;
					}
				}
			}
			else
			{
				BLOCKTYPE Block = m_World->GetBlock((int)floor(GetPosX()), (int)floor(GetPosY()), (int)floor(GetPosZ()) - 1);
				if (!IsBlockRail(Block) && g_BlockIsSolid[Block])
				{
					cBoundingBox bbBlock(Vector3d((int)floor(GetPosX()), (int)floor(GetPosY()), (int)floor(GetPosZ()) - 1), 0.5, 1);
					cBoundingBox bbMinecart(Vector3d(GetPosX(), floor(GetPosY()), GetPosZ() - 1), GetWidth() / 2, GetHeight());

					if (bbBlock.DoesIntersect(bbMinecart))
					{
						SetSpeed(0, 0, 0);
						SetPosZ(floor(GetPosZ()) + 0.65);
						return true;
					}
				}
			}
			break;
		}
		case E_META_RAIL_XM_XP:
		{
			if (GetSpeedX() > 0)
			{
				BLOCKTYPE Block = m_World->GetBlock((int)ceil(GetPosX()), (int)floor(GetPosY()), (int)floor(GetPosZ()));
				if (!IsBlockRail(Block) && g_BlockIsSolid[Block])
				{
					cBoundingBox bbBlock(Vector3d((int)ceil(GetPosX()), (int)floor(GetPosY()), (int)floor(GetPosZ())), 0.5, 1);
					cBoundingBox bbMinecart(Vector3d(GetPosX(), floor(GetPosY()), GetPosZ()), GetWidth() / 2, GetHeight());

					if (bbBlock.DoesIntersect(bbMinecart))
					{
						SetSpeed(0, 0, 0);
						SetPosX(floor(GetPosX()) + 0.4);
						return true;
					}
				}
			}
			else
			{
				BLOCKTYPE Block = m_World->GetBlock((int)floor(GetPosX()) - 1, (int)floor(GetPosY()), (int)floor(GetPosZ()));
				if (!IsBlockRail(Block) && g_BlockIsSolid[Block])
				{
					cBoundingBox bbBlock(Vector3d((int)floor(GetPosX()) - 1, (int)floor(GetPosY()), (int)floor(GetPosZ())), 0.5, 1);
					cBoundingBox bbMinecart(Vector3d(GetPosX() - 1, floor(GetPosY()), GetPosZ()), GetWidth() / 2, GetHeight());

					if (bbBlock.DoesIntersect(bbMinecart))
					{
						SetSpeed(0, 0, 0);
						SetPosX(floor(GetPosX()) + 0.65);
						return true;
					}
				}
			}
			break;
		}			
		case E_META_RAIL_CURVED_ZM_XM:
		case E_META_RAIL_CURVED_ZM_XP:
		case E_META_RAIL_CURVED_ZP_XM:
		case E_META_RAIL_CURVED_ZP_XP:
		{
			BLOCKTYPE BlockXM = m_World->GetBlock((int)floor(GetPosX()) - 1, (int)floor(GetPosY()), (int)floor(GetPosZ()));
			BLOCKTYPE BlockXP = m_World->GetBlock((int)floor(GetPosX()) + 1, (int)floor(GetPosY()), (int)floor(GetPosZ()));
			BLOCKTYPE BlockZM = m_World->GetBlock((int)floor(GetPosX()), (int)floor(GetPosY()), (int)floor(GetPosZ()) + 1);
			BLOCKTYPE BlockZP = m_World->GetBlock((int)floor(GetPosX()), (int)floor(GetPosY()), (int)floor(GetPosZ()) + 1);
			if (
				(!IsBlockRail(BlockXM) && g_BlockIsSolid[BlockXM]) ||
				(!IsBlockRail(BlockXP) && g_BlockIsSolid[BlockXP]) ||
				(!IsBlockRail(BlockZM) && g_BlockIsSolid[BlockZM]) ||
				(!IsBlockRail(BlockZP) && g_BlockIsSolid[BlockZP])
				)
			{
				SetSpeed(0, 0, 0);
				SetPosition((int)floor(GetPosX()) + 0.5, GetPosY(), (int)floor(GetPosZ()) + 0.5);
				return true;
			}
			break;
		}
		default: break;
	}
	return false;
}





void cMinecart::DoTakeDamage(TakeDamageInfo & TDI)
{
	if (TDI.Attacker->IsPlayer() && ((cPlayer *)TDI.Attacker)->IsGameModeCreative())
	{
		Destroy();
		TDI.FinalDamage = GetMaxHealth(); // Instant hit for creative
		super::DoTakeDamage(TDI);
		return; // No drops for creative
	}

	m_LastDamage = TDI.FinalDamage;
	super::DoTakeDamage(TDI);

	m_World->BroadcastEntityMetadata(*this);

	if (GetHealth() <= 0)
	{
		Destroy();
		
		cItems Drops;
		switch (m_Payload)
		{
			case mpNone:
			{
				Drops.push_back(cItem(E_ITEM_MINECART, 1, 0));
				break;
			}
			case mpChest:
			{
				Drops.push_back(cItem(E_ITEM_CHEST_MINECART, 1, 0));
				break;
			}
			case mpFurnace:
			{
				Drops.push_back(cItem(E_ITEM_FURNACE_MINECART, 1, 0));
				break;
			}
			case mpTNT:
			{
				Drops.push_back(cItem(E_ITEM_MINECART_WITH_TNT, 1, 0));
				break;
			}
			case mpHopper:
			{
				Drops.push_back(cItem(E_ITEM_MINECART_WITH_HOPPER, 1, 0));
				break;
			}
			default:
			{
				ASSERT(!"Unhandled minecart type when spawning pickup!");
				return;
			}
		}
		
		m_World->SpawnItemPickups(Drops, GetPosX(), GetPosY(), GetPosZ());
	}
}





void cMinecart::Destroyed()
{
	if (m_bIsOnDetectorRail)
	{
		m_World->SetBlock(m_DetectorRailPosition.x, m_DetectorRailPosition.y, m_DetectorRailPosition.z, E_BLOCK_DETECTOR_RAIL, m_World->GetBlockMeta(m_DetectorRailPosition) & 0x07);
	}
}





///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cEmptyMinecart:

cEmptyMinecart::cEmptyMinecart(double a_X, double a_Y, double a_Z) :
	super(mpNone, a_X, a_Y, a_Z)
{
}





void cEmptyMinecart::OnRightClicked(cPlayer & a_Player)
{
	if (m_Attachee != NULL)
	{
		if (m_Attachee->GetUniqueID() == a_Player.GetUniqueID())
		{
			// This player is already sitting in, they want out.
			a_Player.Detach();
			return;
		}
		
		if (m_Attachee->IsPlayer())
		{
			// Another player is already sitting in here, cannot attach
			return;
		}
		
		// Detach whatever is sitting in this minecart now:
		m_Attachee->Detach();
	}
	
	// Attach the player to this minecart
	a_Player.AttachTo(this);
}





///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cMinecartWithChest:

cMinecartWithChest::cMinecartWithChest(double a_X, double a_Y, double a_Z) :
	super(mpChest, a_X, a_Y, a_Z)
{
}





void cMinecartWithChest::SetSlot(int a_Idx, const cItem & a_Item)
{
	ASSERT((a_Idx >= 0) && (a_Idx < ARRAYCOUNT(m_Items)));
	
	m_Items[a_Idx] = a_Item;
}





void cMinecartWithChest::OnRightClicked(cPlayer & a_Player)
{
	// Show the chest UI window to the player
	// TODO
}





///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cMinecartWithFurnace:

cMinecartWithFurnace::cMinecartWithFurnace(double a_X, double a_Y, double a_Z) :
	super(mpFurnace, a_X, a_Y, a_Z),
	m_IsFueled(false),
	m_FueledTimeLeft(-1)
{
}





void cMinecartWithFurnace::OnRightClicked(cPlayer & a_Player)
{
	if (a_Player.GetEquippedItem().m_ItemType == E_ITEM_COAL)
	{
		if (!a_Player.IsGameModeCreative())
		{
			a_Player.GetInventory().RemoveOneEquippedItem();
		}
		if (!m_IsFueled) // We don't want to change the direction by right clicking it.
		{
			AddSpeed(a_Player.GetLookVector().x, 0, a_Player.GetLookVector().z);
		}
		m_IsFueled = true;
		m_FueledTimeLeft = m_FueledTimeLeft + 600; // The minecart will be active 600 more ticks.
		m_World->BroadcastEntityMetadata(*this);
	}
}





void cMinecartWithFurnace::Tick(float a_Dt, cChunk & a_Chunk)
{
	super::Tick(a_Dt, a_Chunk);

	if (m_IsFueled)
	{
		m_FueledTimeLeft--;
		if (m_FueledTimeLeft < 0)
		{
			m_IsFueled = false;
			m_World->BroadcastEntityMetadata(*this);
			return;
		}

		if (GetSpeed().Length() > 6)
		{
			return;
		}
		AddSpeed(GetSpeed() / 4);
	}
}





///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cMinecartWithTNT:

cMinecartWithTNT::cMinecartWithTNT(double a_X, double a_Y, double a_Z) :
	super(mpTNT, a_X, a_Y, a_Z)
{
}

// TODO: Make it activate when passing over activator rail





///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// cMinecartWithHopper:

cMinecartWithHopper::cMinecartWithHopper(double a_X, double a_Y, double a_Z) :
	super(mpHopper, a_X, a_Y, a_Z)
{
}

// TODO: Make it suck up blocks and travel further than any other cart and physics and put and take blocks
// AND AVARYTHING!!