feat: add ReorientFaceMesh node with metric 3D rotation pipeline

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/test_reorient_face_mesh.py

@@ -0,0 +1,66 @@
+import torch
+import math
+
+def test_input_types_exist():
+    from nodes.reorient_face_mesh import ReorientFaceMesh
+    types = ReorientFaceMesh.INPUT_TYPES()
+    assert "landmarks" in types["required"]
+    assert "face_matrix" in types["required"]
+
+def test_return_types():
+    from nodes.reorient_face_mesh import ReorientFaceMesh
+    assert "FACE_LANDMARKS" in ReorientFaceMesh.RETURN_TYPES
+    assert "FACE_NORMALS" in ReorientFaceMesh.RETURN_TYPES
+
+def test_zero_rotation_preserves_landmarks():
+    from nodes.reorient_face_mesh import ReorientFaceMesh
+    node = ReorientFaceMesh()
+    B = 1
+    landmarks = torch.rand(B, 478, 3)
+    landmarks[..., 0:2] = landmarks[..., 0:2]
+    landmarks[..., 2] = landmarks[..., 2] * 0.1 - 0.05
+    face_matrix = torch.eye(4).unsqueeze(0).expand(B, -1, -1).clone()
+    face_matrix[0, 2, 3] = -5.0
+
+    result_landmarks, normals = node.reorient(
+        landmarks, face_matrix,
+        pitch_offset=0.0, yaw_offset=0.0, roll_offset=0.0,
+        mode="additive"
+    )
+    assert result_landmarks.shape == (B, 478, 3)
+    assert normals.shape == (B, 478, 3)
+    assert torch.allclose(result_landmarks[..., :2], landmarks[..., :2], atol=0.01)
+
+def test_yaw_rotation_shifts_x():
+    from nodes.reorient_face_mesh import ReorientFaceMesh
+    node = ReorientFaceMesh()
+    B = 1
+    landmarks = torch.zeros(B, 478, 3)
+    landmarks[..., 0] = 0.5
+    landmarks[..., 1] = 0.5
+    landmarks[..., 2] = 0.0
+    face_matrix = torch.eye(4).unsqueeze(0).expand(B, -1, -1).clone()
+    face_matrix[0, 2, 3] = -5.0
+
+    result, _ = node.reorient(
+        landmarks, face_matrix,
+        pitch_offset=0.0, yaw_offset=20.0, roll_offset=0.0,
+        mode="additive"
+    )
+    assert result.shape == (B, 478, 3)
+
+def test_normals_are_unit_length():
+    from nodes.reorient_face_mesh import ReorientFaceMesh
+    node = ReorientFaceMesh()
+    B = 2
+    landmarks = torch.rand(B, 478, 3)
+    landmarks[..., 2] *= 0.1
+    face_matrix = torch.eye(4).unsqueeze(0).expand(B, -1, -1).clone()
+    face_matrix[:, 2, 3] = -5.0
+
+    _, normals = node.reorient(
+        landmarks, face_matrix,
+        pitch_offset=10.0, yaw_offset=-15.0, roll_offset=5.0
+    )
+    norms = torch.norm(normals, dim=-1)
+    assert torch.allclose(norms, torch.ones_like(norms), atol=1e-4)