mcserver/source/blocks/BlockLeaves.h

163 lines
4.0 KiB
C++

#pragma once
#include "Block.h"
#include "../MersenneTwister.h"
#include "../cWorld.h"
#include "../BlockArea.h"
// Leaves can be this many blocks that away (inclusive) from the log not to decay
#define LEAVES_CHECK_DISTANCE 6
#define PROCESS_NEIGHBOR(x,y,z) \
switch (a_Area.GetBlockType(x, y, z)) \
{ \
case E_BLOCK_LEAVES: a_Area.SetBlockType(x, y, z, E_BLOCK_SPONGE + i + 1); break; \
case E_BLOCK_LOG: return true; \
}
bool HasNearLog(cBlockArea &a_Area, int a_BlockX, int a_BlockY, int a_BlockZ);
class cBlockLeavesHandler : public cBlockHandler
{
public:
cBlockLeavesHandler(BLOCKTYPE a_BlockID)
: cBlockHandler(a_BlockID)
{
}
virtual int GetDropID() override
{
MTRand rand;
if(rand.randInt(5) == 0)
{
return E_ITEM_SAPLING;
}
return E_ITEM_EMPTY;
}
void OnDestroyed(cWorld *a_World, int a_X, int a_Y, int a_Z) override
{
cBlockHandler::OnDestroyed(a_World, a_X, a_Y, a_Z);
//0.5% chance of dropping an apple
NIBBLETYPE Meta = a_World->GetBlockMeta(a_X, a_Y, a_Z);
//check if Oak (0x1 and 0x2 bit not set)
MTRand rand;
if(!(Meta & 3) && rand.randInt(200) == 100)
{
cItems Drops;
Drops.push_back(cItem(E_ITEM_RED_APPLE, 1, 0));
a_World->SpawnItemPickups(Drops, a_X, a_Y, a_Z);
}
}
virtual void OnNeighborChanged(cWorld *a_World, int a_X, int a_Y, int a_Z) override
{
NIBBLETYPE Meta = a_World->GetBlockMeta(a_X, a_Y, a_Z);
a_World->SetBlockMeta(a_X, a_Y, a_Z, Meta & 0x7); //Unset 0x8 bit so it gets checked for decay
}
virtual bool NeedsRandomTicks() override
{
return true;
}
virtual void OnUpdate(cWorld *a_World, int a_X, int a_Y, int a_Z) override
{
NIBBLETYPE Meta = a_World->GetBlockMeta(a_X, a_Y, a_Z);
if ((Meta & 0x04) != 0)
{
// Player-placed leaves, don't decay
return;
}
if (Meta & 0x8)
{
// These leaves have been checked for decay lately and nothing around them changed
return;
}
// Get the data around the leaves:
cBlockArea Area;
if (!Area.Read(
a_World,
a_X - LEAVES_CHECK_DISTANCE, a_X + LEAVES_CHECK_DISTANCE,
a_Y - LEAVES_CHECK_DISTANCE, a_Y + LEAVES_CHECK_DISTANCE,
a_Z - LEAVES_CHECK_DISTANCE, a_Z + LEAVES_CHECK_DISTANCE,
cBlockArea::baTypes)
)
{
// Cannot check leaves, a chunk is missing too close
return;
}
if (HasNearLog(Area, a_X, a_Y, a_Z))
{
// Wood found, the leaves stay; mark them as checked:
a_World->SetBlockMeta(a_X, a_Y, a_Z, Meta | 0x8);
return;
}
// Decay the leaves:
DropBlock(a_World, a_X, a_Y, a_Z);
a_World->DigBlock(a_X, a_Y, a_Z);
}
};
bool HasNearLog(cBlockArea &a_Area, int a_BlockX, int a_BlockY, int a_BlockZ)
{
// Filter the blocks into a {leaves, log, other (air)} set:
BLOCKTYPE * Types = a_Area.GetBlockTypes();
for (int i = a_Area.GetBlockCount() - 1; i > 0; i--)
{
switch (Types[i])
{
case E_BLOCK_LEAVES:
case E_BLOCK_LOG:
{
break;
}
default:
{
Types[i] = E_BLOCK_AIR;
break;
}
}
} // for i - Types[]
// Perform a breadth-first search to see if there's a log connected within 4 blocks of the leaves block:
// Simply replace all reachable leaves blocks with a sponge block plus iteration (in the Area) and see if we can reach a log in 4 iterations
a_Area.SetBlockType(a_BlockX, a_BlockY, a_BlockZ, E_BLOCK_SPONGE);
for (int i = 0; i < LEAVES_CHECK_DISTANCE; i++)
{
for (int y = a_BlockY - i; y <= a_BlockY + i; y++)
{
for (int z = a_BlockZ - i; z <= a_BlockZ + i; z++)
{
for (int x = a_BlockX - i; x <= a_BlockX + i; x++)
{
if (a_Area.GetBlockType(x, y, z) != E_BLOCK_SPONGE + i)
{
continue;
}
PROCESS_NEIGHBOR(x - 1, y, z);
PROCESS_NEIGHBOR(x + 1, y, z);
PROCESS_NEIGHBOR(x, y, z - 1);
PROCESS_NEIGHBOR(x, y, z + 1);
PROCESS_NEIGHBOR(x, y + 1, z);
PROCESS_NEIGHBOR(x, y - 1, z);
} // for x
} // for z
} // for y
} // for i - BFS iterations
return false;
}