Add chunk example with palette and section unpacking, and configure .gitignore

examples/chunks/main.go

@@ -0,0 +1,80 @@
+package main
+
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"io"
+	"math"
+
+	"github.com/admin-else/queser"
+)
+
+func UnpackIndirectPalette(r io.Reader, bitsPerEntry uint8, numberOfEntries int) (err error) {
+	var palletLen queser.VarInt
+	palletLen, err = palletLen.Decode(r)
+	if err != nil {
+		return
+	}
+	var pallet []int32 // remember we can't use make because this is user-controlled data
+	for range palletLen {
+		var entry queser.VarInt
+		entry, err = queser.VarInt(0).Decode(r)
+		if err != nil {
+			return
+		}
+		pallet = append(pallet, int32(entry))
+	}
+	entriesPerLong := int(64 / bitsPerEntry)
+	numberOfLongs := int(math.Ceil(float64(numberOfEntries) / float64(entriesPerLong)))
+	var data []uint64
+	for range numberOfLongs {
+		var entry uint64
+		err = binary.Read(r, binary.BigEndian, &entry)
+		if err != nil {
+			return
+		}
+		data = append(data, entry)
+	}
+	fmt.Println(data)
+	return
+}
+
+func GetBit(data []uint64, index, bpe int32) uint64 {
+	// net.minecraft.util.collection.PackedIntegerArray
+	return 1
+}
+
+func UnpackPalette(r io.Reader, numberOfEntries int) (err error) {
+	var bitsPerEntry uint8
+	err = binary.Read(r, binary.BigEndian, &bitsPerEntry)
+	if err != nil {
+		return
+	}
+	err = UnpackIndirectPalette(r, bitsPerEntry, numberOfEntries)
+	return
+}
+
+func UnpackSection(r io.Reader) (err error) {
+	var blockCount int16
+	err = binary.Read(r, binary.BigEndian, &blockCount)
+	if err != nil {
+		return
+	}
+	err = UnpackPalette(r, 4096) // 4096 is the number of blocks in a chunk
+	return
+}
+
+func mainE() (err error) {
+	fmt.Println(packet.X*16, packet.Z*16)
+	b := bytes.NewBuffer(packet.ChunkData.Val)
+	err = UnpackSection(b)
+	return
+}
+
+func main() {
+	err := mainE()
+	if err != nil {
+		panic(err)
+	}
+}