diff options
Diffstat (limited to 'src/Items/ItemEyeOfEnder.h')
| -rw-r--r-- | src/Items/ItemEyeOfEnder.h | 144 |
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); + } } ; |