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#pragma once
#include "BlockHandler.h"
class cBlockEndPortalFrameHandler final :
public cYawRotator<cBlockHandler, 0x03,
E_META_END_PORTAL_FRAME_ZP,
E_META_END_PORTAL_FRAME_XM,
E_META_END_PORTAL_FRAME_ZM,
E_META_END_PORTAL_FRAME_XP
>
{
using Super = cYawRotator<
cBlockHandler, 0x03,
E_META_END_PORTAL_FRAME_ZP,
E_META_END_PORTAL_FRAME_XM,
E_META_END_PORTAL_FRAME_ZM,
E_META_END_PORTAL_FRAME_XP
>;
public:
using Super::Super;
private:
virtual void OnPlaced(cChunkInterface & a_ChunkInterface, cWorldInterface & a_WorldInterface, Vector3i a_BlockPos, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta) const override
{
// E_META_END_PORTAL_FRAME_EYE is the bit which signifies the eye of ender is in it.
// LOG("PortalPlaced, meta %d", a_BlockMeta);
if ((a_BlockMeta & E_META_END_PORTAL_FRAME_EYE) == E_META_END_PORTAL_FRAME_EYE)
{
// LOG("Location is %d %d %d", a_BlockX, a_BlockY, a_BlockZ);
// Direction is the first two bits, masked by 0x3
FindAndSetPortal(a_BlockPos, a_BlockMeta & 3, a_ChunkInterface, a_WorldInterface);
}
}
/** Returns false if portal cannot be made, true if portal was made. */
static bool FindAndSetPortal(Vector3i a_FirstFrame, NIBBLETYPE a_Direction, cChunkInterface & a_ChunkInterface, cWorldInterface & a_WorldInterface)
{
/*
PORTAL FINDING ALGORITH
=======================
- Get clicked base block
- Check diagonally (clockwise) for another portal block
- if exists, and has eye, Continue. Abort if any are facing the wrong direction.
- if doesn't exist, check horizontally (the block to the left of this block). Abort if there is no horizontal block.
- After a corner has been met, traverse the portal clockwise, ensuring valid portal frames connect the rectangle.
- Track the NorthWest Corner, and the dimensions.
- If dimensions are valid, create the portal.
*/
static_assert((E_META_END_PORTAL_FRAME_ZM - E_META_END_PORTAL_FRAME_XM) == 1, "Should be going clockwise");
const int MIN_PORTAL_WIDTH = 3;
const int MAX_PORTAL_WIDTH = 4;
// Directions to use for the clockwise traversal.
static const Vector3i Left[] =
{
{ 1, 0, 0}, // 0, South, left block is East / XP
{ 0, 0, 1}, // 1, West, left block is South / ZP
{-1, 0, 0}, // 2, North, left block is West / XM
{ 0, 0, -1}, // 3, East, left block is North / ZM
};
static const Vector3i LeftForward[] =
{
{ 1, 0, 1}, // 0, South, left block is SouthEast / XP ZP
{-1, 0, 1}, // 1, West, left block is SouthWest / XM ZP
{-1, 0, -1}, // 2, North, left block is NorthWest / XM ZM
{ 1, 0, -1}, // 3, East, left block is NorthEast / XP ZM
};
int EdgesComplete = -1; // We start search _before_ finding the first edge
Vector3i NorthWestCorner;
int EdgeWidth[4] = { 1, 1, 1, 1 };
NIBBLETYPE CurrentDirection = a_Direction;
Vector3i CurrentPos = a_FirstFrame;
// Scan clockwise until we have seen all 4 edges
while (EdgesComplete < 4)
{
// Check if we are at a corner
Vector3i NextPos = CurrentPos + LeftForward[CurrentDirection];
if (IsPortalFrame(a_ChunkInterface.GetBlock(NextPos)))
{
// We have found the corner, move clockwise to next edge
if (CurrentDirection == E_META_END_PORTAL_FRAME_XP)
{
// We are on the NW (XM, ZM) Corner
// Relative to the previous frame, the portal should appear to the right of this portal frame.
NorthWestCorner = NextPos - Left[CurrentDirection];
}
if (EdgesComplete == -1)
{
// Reset current width, we will revisit it last
EdgeWidth[CurrentDirection] = 1;
}
// Rotate 90 degrees clockwise
CurrentDirection = (CurrentDirection + 1) % 4;
EdgesComplete++;
}
else
{
// We are not at a corner, keep walking the edge
NextPos = CurrentPos + Left[CurrentDirection];
EdgeWidth[CurrentDirection]++;
if (EdgeWidth[CurrentDirection] > MAX_PORTAL_WIDTH)
{
// Don't build a portal that is too long.
return false;
}
}
if (!IsValidFrameAtPos(a_ChunkInterface, NextPos, CurrentDirection))
{
// Neither the edge nor the corner are valid portal blocks.
return false;
}
CurrentPos = NextPos;
}
if ((EdgeWidth[0] != EdgeWidth[2]) || (EdgeWidth[1] != EdgeWidth[3]))
{
// Mismatched Portal Dimensions.
return false;
}
if ((EdgeWidth[0] < MIN_PORTAL_WIDTH) || (EdgeWidth[1] < MIN_PORTAL_WIDTH))
{
// Portal too small.
return false;
}
// LOG("NW corner (low corner) %d %d %d", Corner.x, Corner.y, Corner.z);
// LOG("%d by %d", Width[0], Width[1]);
for (int i = 0; i < EdgeWidth[0]; i++)
{
for (int j = 0; j < EdgeWidth[1]; j++)
{
a_ChunkInterface.SetBlock(NorthWestCorner.x + i, NorthWestCorner.y, NorthWestCorner.z + j, E_BLOCK_END_PORTAL, 0);
// TODO: Create block entity so portal doesn't become invisible on relog.
}
}
return true;
}
/** Return true if this block is a portal frame, has an eye, and is facing the correct direction. */
static bool IsValidFrameAtPos(cChunkInterface & a_ChunkInterface, Vector3i a_BlockPos, NIBBLETYPE a_ShouldFace)
{
BLOCKTYPE BlockType;
NIBBLETYPE BlockMeta;
return (
a_ChunkInterface.GetBlockTypeMeta(a_BlockPos, BlockType, BlockMeta) &&
(BlockType == E_BLOCK_END_PORTAL_FRAME) &&
(BlockMeta == (a_ShouldFace | E_META_END_PORTAL_FRAME_EYE))
);
}
/** Return true if this block is a portal frame. */
static bool IsPortalFrame(BLOCKTYPE BlockType)
{
return (BlockType == E_BLOCK_END_PORTAL_FRAME);
}
virtual ColourID GetMapBaseColourID(NIBBLETYPE a_Meta) const override
{
UNUSED(a_Meta);
return 27;
}
};
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