items and struture loading

level/packet.go

@@ -2,8 +2,6 @@ package level
 
 import (
 	"encoding/binary"
-	"errors"
-	"fmt"
 	"io"
 	"math"
 
@@ -22,7 +20,8 @@ func UnpackArrayPalette(r io.Reader, bitsPerEntry uint8, numberOfEntries int) (d
 	}
 	var pallet []int32 // remember we can't use make because this is user-controlled data
 	for range palletLen {
-		entry, err := proto_base.DecodeVarInt(r)
+		var entry int32
+		entry, err = proto_base.DecodeVarInt(r)
 		if err != nil {
 			return
 		}
@@ -76,20 +75,18 @@ func LongsToData(data []uint64, n, bpe int32) (ret []int32) {
 	return
 }
 
+// UnpackBlockData minecraft does this at net.minecraft.world.chunk.PaletteProvider
 func UnpackBlockData(r io.Reader) (blocks []int32, err error) {
 	var bitsPerEntry uint8
 	err = binary.Read(r, binary.BigEndian, &bitsPerEntry)
 	if err != nil {
 		return
 	}
-	fmt.Println("blocks bpe", bitsPerEntry)
 	switch bitsPerEntry {
 	case 0:
 		blocks, err = UnpackSingleValuePalette(r, BlocksPerChunkSection)
-	case 1, 2, 3, 4:
+	case 1, 2, 3, 4, 5, 6, 7, 8:
 		blocks, err = UnpackArrayPalette(r, bitsPerEntry, BlocksPerChunkSection)
-	case 5, 6, 7, 8:
-		err = errors.New("unimplemented")
 	default:
 		blocks, err = UnpackLongData(r, bitsPerEntry, BlocksPerChunkSection)
 	}
@@ -106,7 +103,6 @@ func UnpackBiomeData(r io.Reader) (biomes []int32, err error) {
 	if err != nil {
 		return
 	}
-	fmt.Println("biome bpe", bitsPerEntry)
 	switch bitsPerEntry {
 	case 0:
 		biomes, err = UnpackSingleValuePalette(r, BiomesPerChunkSection)
@@ -132,9 +128,18 @@ func UnpackSection(r io.Reader) (blocks, biomes []int32, err error) {
 		return
 	}
 	biomes, err = UnpackBiomeData(r)
-	if err != nil {
-		return
+	return
+}
+
+func UnpackNSections(r io.Reader, n int) (blocks, biomes [][]int32, err error) {
+	for range n {
+		var blocksSection, biomesSections []int32
+		blocksSection, biomesSections, err = UnpackSection(r)
+		if err != nil {
+			return
+		}
+		blocks = append(blocks, blocksSection)
+		biomes = append(biomes, biomesSections)
 	}
-
 	return
 }

level/structure.go

@@ -0,0 +1,44 @@
+package level
+
+import (
+	"github.com/admin-else/strom/nbt"
+	"github.com/go-viper/mapstructure/v2"
+)
+
+func LoadStructure(fileName string) (s *Structure, err error) {
+	n, err := nbt.ReadFilePath(fileName)
+	if err != nil {
+		return
+	}
+	s = &Structure{}
+	err = mapstructure.Decode(n.Value, s)
+	return
+}
+
+type Structure struct {
+	DataVersion int32
+	Blocks      []struct {
+		Pos   [3]int32
+		State int
+	}
+	Palette []struct {
+		Name       string
+		Properties map[string]string
+	}
+	Size [3]int32
+}
+
+func (s *Structure) GetBlock(x, y, z int32) (name string) {
+	for _, block := range s.Blocks {
+		if block.Pos[0] == x && block.Pos[1] == y && block.Pos[2] == z {
+			palletIndex := block.State
+
+			if palletIndex >= len(s.Palette) {
+				return ""
+			}
+
+			return s.Palette[palletIndex].Name
+		}
+	}
+	return ""
+}