//Returns the chunk at the coordinates, also returns if the chunk existed
//before this
func (mw *MsgpackSystem) Chunk(x, z int) (*Chunk, bool) {
reg := mw.region(x>>5, z>>5)
reg.RLock()
rx := x & 0x1F
rz := z & 0x1F
idx := rx | (rz << 5)
offset := reg.Offsets[idx]
count := reg.SectionCounts[idx]
reg.RUnlock()
if offset == 0 {
return &Chunk{X: x, Z: z}, false
}
section := io.NewSectionReader(reg.file, int64(offset)*regionSectionSize, int64(count)*regionSectionSize)
gz, err := gzip.NewReader(section)
if err != nil {
panic(err)
}
chunk := &Chunk{}
err = msgpack.NewDecoder(gz).Decode(chunk)
gz.Close()
if err != nil {
panic(err)
}
return chunk, true
}
//Reads key into the passed struct pointer
func (mw *MsgpackSystem) Read(key string, v interface{}) error {
f, err := os.Open(filepath.Join(mw.path, "data", key+".nether"))
if err != nil {
return err
}
defer f.Close()
return msgpack.NewDecoder(f).Decode(v)
}
func (mw *MsgpackSystem) readLevel(level string) {
f, err := os.Open(level)
if err != nil {
panic(err)
}
defer f.Close()
err = msgpack.NewDecoder(f).Decode(mw)
if err != nil {
panic(err)
}
}
func (mw *MsgpackSystem) region(x, z int) *region {
key := (uint64(int32(x)) & 0xFFFFFFFF) | ((uint64(int32(z)) & 0xFFFFFFFF) << 32)
mw.regionLock.RLock()
reg, ok := mw.regions[key]
mw.regionLock.RUnlock()
if ok {
return reg
}
mw.regionLock.Lock()
reg, ok = mw.regions[key]
if ok {
mw.regionLock.Unlock()
return reg
}
reg = ®ion{}
file, err := os.OpenFile(filepath.Join(mw.path, "regions", fmt.Sprintf("%016X.region", key)), os.O_RDWR|os.O_CREATE, 0666)
if err != nil {
panic(err)
}
msgpack.NewDecoder(file).Decode(reg)
reg.file = file
reg.usedLocations = []bool{true, true, true}
for i, off := range reg.Offsets {
if off == 0 {
continue
}
count := reg.SectionCounts[i]
if len(reg.usedLocations) < off+count {
temp := reg.usedLocations
reg.usedLocations = make([]bool, off+count)
copy(reg.usedLocations, temp)
}
for j := off; j < off+count; j++ {
reg.usedLocations[j] = true
}
}
reg.Save()
mw.regions[key] = reg
mw.regionLock.Unlock()
return reg
}
//Loads the world by name
func GetWorld(name string, tryClose chan TryClose) *World {
root := filepath.Join("./worlds/", name)
f, err := os.Open(filepath.Join(root, "netherrack.meta"))
if err != nil {
return nil
}
defer f.Close()
meta := netherrackMeta{}
msgpack.NewDecoder(f).Decode(&meta)
sys, ok := systems[meta.SystemName]
if !ok {
panic("Unknown world system")
}
system := sys()
gen, ok := generators[meta.GeneratorName]
if !ok {
panic("Unknown world generator")
}
generator := gen()
w := &World{
Name: name,
system: system,
generator: generator,
tryClose: tryClose,
}
w.init()
w.system.Init(filepath.Join("./worlds/", w.Name))
w.system.Read("levelData", &w.worldData)
go w.run()
return w
}
