From 997594d7c36c9bb123407856561e95b61d39b623 Mon Sep 17 00:00:00 2001
From: adman <adman.else@gmail.com>
Date: Mon, 20 Apr 2026 20:23:25 +0200
Subject: [PATCH] fix chunk sections being one

---
 level/chunk_builder.go | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/level/chunk_builder.go b/level/chunk_builder.go
index 1903f9e..ad242a3 100644
--- a/level/chunk_builder.go
+++ b/level/chunk_builder.go
@@ -37,8 +37,16 @@ func (cb *ChunkBuilder) FillAllById(block, biome int32) {
 	cb.Blocks = make([][]int32, numSections)
 	cb.Biomes = make([][]int32, numSections)
 	for i := range cb.Blocks {
-		cb.Blocks[i] = blockSection
-		cb.Biomes[i] = biomeSection
+
+		// Otherwise setting one block will set it also in all other sections because the slice is the same
+		var blocks = make([]int32, BlocksPerChunkSection)
+		copy(blocks, blockSection)
+
+		var biomes = make([]int32, BiomesPerChunkSection)
+		copy(biomes, biomeSection)
+
+		cb.Blocks[i] = blocks
+		cb.Biomes[i] = biomes
 	}
 	return
 }