yes

mc/data/multi_noise_test.go

@@ -1,6 +1,7 @@
 package data
 
 import (
+	"math"
 	"testing"
 )
 
@@ -32,3 +33,44 @@ func TestMultiNoiseLookup_NetherOrigin(t *testing.T) {
 		t.Errorf("nether origin = %s, want minecraft:nether_wastes", biome)
 	}
 }
+
+func TestMultiNoiseLookup_BVHMatchesBruteForce(t *testing.T) {
+	data, err := LoadMultiNoise("1.21.11")
+	if err != nil {
+		t.Fatalf("LoadMultiNoise: %v", err)
+	}
+
+	brute := func(preset string, q point6) (string, int64) {
+		best := result{dist: int64(math.MaxInt64)}
+		for _, p := range data.Presets[preset] {
+			d := q.dist(p)
+			if d < best.dist {
+				best.dist = d
+				best.biome = p.Biome
+			}
+		}
+		return best.biome, best.dist
+	}
+
+	presets := []string{MultiNoiseOverworld, MultiNoiseNether}
+	for _, preset := range presets {
+		for i := 0; i < 1000; i++ {
+			q := point6{
+				t: int64(i%20000 - 10000),
+				h: int64((i*7)%20000 - 10000),
+				c: int64((i*13)%20000 - 10000),
+				e: int64((i*17)%20000 - 10000),
+				d: int64((i*3)%20000 - 10000),
+				w: int64((i*11)%20000 - 10000),
+			}
+			wantBiome, wantDist := brute(preset, q)
+			gotBiome, err := data.Lookup(preset, q.t, q.h, q.c, q.e, q.d, q.w)
+			if err != nil {
+				t.Fatalf("Lookup(%s): %v", preset, err)
+			}
+			if gotBiome != wantBiome {
+				t.Errorf("preset=%s query=%+v got=%s want=%s dist=%d", preset, q, gotBiome, wantBiome, wantDist)
+			}
+		}
+	}
+}