diff --git a/LEGO1/lego/sources/misc/legounknown.cpp b/LEGO1/lego/sources/misc/legounknown.cpp
index 14178e44..6b4a710e 100644
--- a/LEGO1/lego/sources/misc/legounknown.cpp
+++ b/LEGO1/lego/sources/misc/legounknown.cpp
@@ -27,8 +27,52 @@ void LegoUnknown::FUN_1009a140(Vector3& p_point1, Vector3& p_point2, Vector3& p_
 	}
 }
 
-// STUB: LEGO1 0x1009a1e0
-LegoResult LegoUnknown::FUN_1009a1e0(float, Matrix4&, Vector3&, LegoU32)
+// FUNCTION: LEGO1 0x1009a1e0
+// FUNCTION: BETA10 0x10182d61
+LegoResult LegoUnknown::FUN_1009a1e0(float p_f1, Matrix4& p_mat, Vector3& p_v, LegoU32 p_und)
 {
-	return FAILURE;
+	Vector3 v1(p_mat[3]);
+	Vector3 v2(p_mat[0]);
+	Vector3 v3(p_mat[1]);
+	Vector3 v4(p_mat[2]);
+
+	if (p_f1 <= 0.001) {
+		v1 = m_unk0x00[0];
+		v4 = m_unk0x00[1];
+	}
+	else if (p_f1 >= 0.999) {
+		v1 = m_unk0x00[0];
+		((Vector3&) v2).Add(&m_unk0x00[1]);
+		((Vector3&) v3).Add(&m_unk0x00[2]);
+		((Vector3&) v4).Add(&m_unk0x00[3]);
+
+		for (LegoS32 i = 0; i < 3; i++) {
+			v4[i] = m_unk0x00[1][i] + m_unk0x00[2][i] * 2.0f + m_unk0x00[3][i] * 3.0f;
+		}
+	}
+	else {
+		float local30 = p_f1 * p_f1;
+		float local34 = local30 * p_f1;
+
+		for (LegoS32 i = 0; i < 3; i++) {
+			v1[i] = m_unk0x00[0][i] + m_unk0x00[1][i] * p_f1 + m_unk0x00[2][i] * local30 + m_unk0x00[3][i] * local34;
+			v4[i] = m_unk0x00[1][i] + m_unk0x00[2][i] * p_f1 * 2.0f + m_unk0x00[3][i] * local30 * 3.0f;
+		}
+	}
+
+	if (p_und) {
+		((Vector3&) v4).Mul(-1.0f);
+	}
+
+	if (v4.Unitize() != 0) {
+		return FAILURE;
+	}
+
+	v2.EqualsCross(&p_v, &v4);
+	if (v2.Unitize() != 0) {
+		return FAILURE;
+	}
+
+	v3.EqualsCross(&v4, &v2);
+	return SUCCESS;
 }
diff --git a/LEGO1/lego/sources/misc/legounknown.h b/LEGO1/lego/sources/misc/legounknown.h
index 03eafcee..1d0d1aef 100644
--- a/LEGO1/lego/sources/misc/legounknown.h
+++ b/LEGO1/lego/sources/misc/legounknown.h
@@ -13,7 +13,7 @@ class LegoUnknown {
 	~LegoUnknown();
 
 	void FUN_1009a140(Vector3& p_point1, Vector3& p_point2, Vector3& p_point3, Vector3& p_point4);
-	LegoResult FUN_1009a1e0(float, Matrix4&, Vector3&, LegoU32);
+	LegoResult FUN_1009a1e0(float p_f1, Matrix4& p_mat, Vector3& p_v, LegoU32 p_und);
 
 private:
 	Mx3DPointFloat m_unk0x00[4]; // 0x00
diff --git a/LEGO1/realtime/vector.h b/LEGO1/realtime/vector.h
index 198ed14b..01a15d49 100644
--- a/LEGO1/realtime/vector.h
+++ b/LEGO1/realtime/vector.h
@@ -104,7 +104,7 @@ class Vector2 {
 
 		if (sq > 0.0f) {
 			float root = sqrt(sq);
-			if (root > 0) {
+			if (root > 0.0f) {
 				DivScalarImpl(&root);
 				return 0;
 			}