From 68cced73afe546328cf94ed07c57deee47bfadec Mon Sep 17 00:00:00 2001 From: Tiger Wang Date: Sun, 20 Sep 2020 14:50:52 +0100 Subject: BlockHandler initialisation is a constant expression (#4891) * BlockHandler initialisation is a constant expression If we can't make it all namespaces, this is the next best I guess. + Tag handlers constexpr, const as needed + Inherit constructors * Privatise handler functions * More constexpr Co-authored-by: Alexander Harkness --- src/Blocks/BlockEndPortalFrame.h | 175 ++++++++++++++++++++++++++++++++++++--- 1 file changed, 165 insertions(+), 10 deletions(-) (limited to 'src/Blocks/BlockEndPortalFrame.h') diff --git a/src/Blocks/BlockEndPortalFrame.h b/src/Blocks/BlockEndPortalFrame.h index 567de8bcc..2aa0327cf 100644 --- a/src/Blocks/BlockEndPortalFrame.h +++ b/src/Blocks/BlockEndPortalFrame.h @@ -25,14 +25,9 @@ class cBlockEndPortalFrameHandler: public: - cBlockEndPortalFrameHandler(BLOCKTYPE a_BlockType): - Super(a_BlockType) - { - } - - - + using Super::Super; +private: virtual bool GetPlacementBlockTypeMeta( cChunkInterface & a_ChunkInterface, @@ -41,7 +36,7 @@ public: eBlockFace a_ClickedBlockFace, const Vector3i a_CursorPos, BLOCKTYPE & a_BlockType, NIBBLETYPE & a_BlockMeta - ) override + ) const override { a_BlockType = m_BlockType; a_BlockMeta = YawToMetaData(a_Player.GetYaw()); @@ -82,7 +77,167 @@ public: - virtual bool IsClickedThrough(void) override + 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 bool IsClickedThrough(void) const override { // TODO: Colision return true; @@ -92,7 +247,7 @@ public: - virtual ColourID GetMapBaseColourID(NIBBLETYPE a_Meta) override + virtual ColourID GetMapBaseColourID(NIBBLETYPE a_Meta) const override { UNUSED(a_Meta); return 27; -- cgit v1.2.3