summaryrefslogtreecommitdiffstats
path: root/src/Items/ItemEyeOfEnder.h
diff options
context:
space:
mode:
Diffstat (limited to 'src/Items/ItemEyeOfEnder.h')
-rw-r--r--src/Items/ItemEyeOfEnder.h144
1 files changed, 144 insertions, 0 deletions
diff --git a/src/Items/ItemEyeOfEnder.h b/src/Items/ItemEyeOfEnder.h
index 3849feb00..6a636cb12 100644
--- a/src/Items/ItemEyeOfEnder.h
+++ b/src/Items/ItemEyeOfEnder.h
@@ -46,6 +46,11 @@ public:
{
a_Player->GetInventory().RemoveOneEquippedItem();
}
+
+ cChunkInterface ChunkInterface(a_World->GetChunkMap());
+
+ // Try to spawn portal:
+ FindAndSetPortal(a_ClickedBlockPos, FacingMeta & 3, ChunkInterface, *a_World);
return true;
}
}
@@ -58,6 +63,145 @@ public:
return false;
}
+
+
+
+ /** 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;
+ }
+
+ 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);
+ }
+ }
+ 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);
+ }
} ;