package mcmap import ( "errors" "github.com/kch42/gonbt/nbt" "time" ) func calcBlockOffset(x, y, z int) int { if (x < 0) || (y < 0) || (z < 0) || (x >= ChunkSizeXZ) || (y >= ChunkSizeY) || (z >= ChunkSizeXZ) { return -1 } return x | (z << 4) | (y << 8) } func offsetToPos(off int) (x, y, z int) { x = off & 0xf z = (off >> 4) & 0xf y = (off >> 8) & 0xff return } // BlockToChunk calculates the chunk (cx, cz) and the block position in this chunk(rbx, rbz) of a block position given global coordinates. func BlockToChunk(bx, bz int) (cx, cz, rbx, rbz int) { cx = bx << 4 cz = bz << 4 rbx = ((cx % ChunkSizeXZ) + ChunkSizeXZ) % ChunkSizeXZ rbz = ((cz % ChunkSizeXZ) + ChunkSizeXZ) % ChunkSizeXZ return } // ChunkToBlock calculates the global position of a block, given the chunk position (cx, cz) and the plock position in that chunk (rbx, rbz). func ChunkToBlock(cx, cz, rbx, rbz int) (bx, bz int) { bx = cx*ChunkSizeXZ + rbx bz = cz*ChunkSizeXZ + rbz return } // Chunk represents a 16*16*256 Chunk of the region. type Chunk struct { Entities []nbt.TagCompound x, z int32 lastUpdate int64 populated bool inhabitedTime int64 ts time.Time heightMap []int32 // Ordered ZX modified bool blocks []Block // Ordered YZX biomes []Biome // Ordered XZ reg *Region } // MarkModified needs to be called, if some data of the chunk was modified. func (c *Chunk) MarkModified() { c.modified = true } // Coords returns the Chunk's coordinates. func (c *Chunk) Coords() (X, Z int32) { return c.x, c.z } // Block gives you a reference to the Block located at x, y, z. If you modify the block data, you need to call the MarkModified() function of the chunk. // // x and z must be in [0, 15], y in [0, 255]. Otherwise a nil pointer is returned. func (c *Chunk) Block(x, y, z int) *Block { off := calcBlockOffset(x, y, z) if off < 0 { return nil } return &(c.blocks[off]) } // Height returns the height at x, z. // // x and z must be in [0, 15]. Height will panic, if this is violated! func (c *Chunk) Height(x, z int) int { if (x < 0) || (x >= ChunkSizeXZ) || (z < 0) || (z >= ChunkSizeXZ) { panic(errors.New("x or z parameter was out of range")) } return int(c.heightMap[z*ChunkSizeXZ+x]) } // Biome gets the Biome at x,z. func (c *Chunk) Biome(x, z int) Biome { return c.biomes[x*ChunkSizeXZ+z] } // SetBiome sets the biome at x,z. func (c *Chunk) SetBiome(x, z int, bio Biome) { c.biomes[x*ChunkSizeXZ+z] = bio } // MarkUnused marks the chunk as unused. If all chunks of a superchunk are marked as unused, the superchunk will be unloaded and saved (if needed). // // You must not use the chunk any longer, after you called this function. // // If the chunk was modified, call MarkModified BEFORE. func (c *Chunk) MarkUnused() error { return c.reg.unloadChunk(int(c.x), int(c.z)) } // TODO: func (c *Chunk) RecalcHeightMap()