diff --git a/layers.c b/layers.c
index 137dabe..c10ae2a 100644
--- a/layers.c
+++ b/layers.c
@@ -1398,6 +1398,28 @@ int sampleBiomeNoise(const BiomeNoise *bn, int64_t *np, int x, int y, int z,
     return id;
 }
 
+void genBiomeNoiseChunkSection(const BiomeNoise *bn, int out[4][4][4],
+    int cx, int cy, int cz, uint64_t *dat)
+{
+    uint64_t buf = 0;
+    int i, j, k;
+    int x4 = cx << 2, y4 = cy << 2, z4 = cz << 2;
+    if (dat == NULL)
+        dat = &buf;
+    if (*dat == 0)
+    {   // try to determine the ending point of the last chunk section
+        sampleBiomeNoise(bn, NULL, x4+3, y4-1, z4+3, dat, 0);
+    }
+
+    // iteration order is important
+    for (i = 0; i < 4; ++i) {
+        for (j = 0; j < 4; ++j) {
+            for (k = 0; k < 4; ++k) {
+                out[i][j][k] = sampleBiomeNoise(bn, NULL, x4+i, y4+j, z4+k, dat, 0);
+            }
+        }
+    }
+}
 
 static void genBiomeNoise3D(const BiomeNoise *bn, int *out, Range r, int opt)
 {
diff --git a/layers.h b/layers.h
index 33adf69..8a2cc57 100644
--- a/layers.h
+++ b/layers.h
@@ -445,6 +445,18 @@ void initBiomeNoise(BiomeNoise *bn, int mc);
 void setBiomeSeed(BiomeNoise *bn, uint64_t seed, int large);
 int sampleBiomeNoise(const BiomeNoise *bn, int64_t *np, int x, int y, int z,
     uint64_t *dat, uint32_t flags);
+/**
+ * Currently, in 1.18, we have to generate biomes a chunk at a time to get an
+ * accurate mapping of the biomes in the level storage, as there is no longer a
+ * unique mapping from noise points to biomes (MC-241546). Note that the results
+ * from this are not suitable for chunk population/structure generation.
+ * The output is in the form out[x][y][z] for the 64 biome points in the chunk
+ * section. The coordinates {cx,cy,cz} are all at scale 1:16 and the 'dat'
+ * argument should be the previous noise sampling and can be left NULL.
+ */
+void genBiomeNoiseChunkSection(const BiomeNoise *bn, int out[4][4][4],
+    int cx, int cy, int cz, uint64_t *dat);
+
 /**
  * The scaled biome noise generation applies for the Overworld version 1.18.
  * The 'sha' hash of the seed is only required for voronoi at scale 1:1.