add flip node

tests/test_nodes.py

@@ -256,6 +256,81 @@ def test_rotate_field_overlay_warning():
     print("  PASS\n")
 
 
+def test_flip_field():
+    print("=== Test: FlipField ===")
+    from backend.nodes.flip_field import FlipField
+    from backend.node_registry import get_node_info
+
+    node = FlipField()
+    data = np.arange(1, 10, dtype=np.float64).reshape(3, 3)
+    markup_overlay = {
+        "kind": "markup",
+        "shapes": [
+            {"kind": "line", "x1": 0.1, "y1": 0.2, "x2": 0.9, "y2": 0.8, "width": 2, "color": "#ffffff"},
+            {"kind": "rectangle", "x1": 0.15, "y1": 0.1, "x2": 0.45, "y2": 0.6, "width": 3, "color": "#ff0000"},
+        ],
+    }
+    annotation_overlay = {
+        "kind": "annotation",
+        "show_scale_bar": True,
+        "show_color_map": False,
+        "text_size": 14.0,
+    }
+    field = DataField(
+        data=data,
+        xreal=3.0,
+        yreal=4.0,
+        xoff=10.0,
+        yoff=20.0,
+        si_unit_xy="nm",
+        si_unit_z="nm",
+        overlays=[markup_overlay, annotation_overlay],
+    )
+
+    assert get_node_info("FlipField")["category"] == "Modify"
+
+    flipped_x, = node.process(field, axis="x")
+    assert np.array_equal(flipped_x.data, np.flipud(data))
+    assert flipped_x.xreal == field.xreal
+    assert flipped_x.yreal == field.yreal
+    assert flipped_x.xoff == field.xoff
+    assert flipped_x.yoff == field.yoff
+    assert flipped_x.si_unit_xy == field.si_unit_xy
+    assert flipped_x.si_unit_z == field.si_unit_z
+    assert np.isclose(flipped_x.overlays[0]["shapes"][0]["x1"], 0.1)
+    assert np.isclose(flipped_x.overlays[0]["shapes"][0]["y1"], 0.8)
+    assert np.isclose(flipped_x.overlays[0]["shapes"][0]["x2"], 0.9)
+    assert np.isclose(flipped_x.overlays[0]["shapes"][0]["y2"], 0.2)
+    assert np.isclose(flipped_x.overlays[0]["shapes"][1]["x1"], 0.15)
+    assert np.isclose(flipped_x.overlays[0]["shapes"][1]["y1"], 0.4)
+    assert np.isclose(flipped_x.overlays[0]["shapes"][1]["x2"], 0.45)
+    assert np.isclose(flipped_x.overlays[0]["shapes"][1]["y2"], 0.9)
+    assert flipped_x.overlays[1] == annotation_overlay
+
+    flipped_y, = node.process(field, axis="y")
+    assert np.array_equal(flipped_y.data, np.fliplr(data))
+    assert np.isclose(flipped_y.overlays[0]["shapes"][0]["x1"], 0.9)
+    assert np.isclose(flipped_y.overlays[0]["shapes"][0]["y1"], 0.2)
+    assert np.isclose(flipped_y.overlays[0]["shapes"][0]["x2"], 0.1)
+    assert np.isclose(flipped_y.overlays[0]["shapes"][0]["y2"], 0.8)
+    assert np.isclose(flipped_y.overlays[0]["shapes"][1]["x1"], 0.55)
+    assert np.isclose(flipped_y.overlays[0]["shapes"][1]["y1"], 0.1)
+    assert np.isclose(flipped_y.overlays[0]["shapes"][1]["x2"], 0.85)
+    assert np.isclose(flipped_y.overlays[0]["shapes"][1]["y2"], 0.6)
+    assert flipped_y.overlays[1] == annotation_overlay
+
+    assert field.overlays[0]["shapes"][0]["x1"] == markup_overlay["shapes"][0]["x1"]
+    assert field.overlays[0]["shapes"][0]["y1"] == markup_overlay["shapes"][0]["y1"]
+
+    try:
+        node.process(field, axis="diagonal")
+        raise AssertionError("Expected invalid flip axis to raise ValueError")
+    except ValueError:
+        pass
+
+    print("  PASS\n")
+
+
 def test_view3d_normalizes_small_physical_extents_for_display():
     print("=== Test: View3D extent normalization ===")
     from backend.nodes.view_3d import View3D
@@ -2437,6 +2512,7 @@ if __name__ == "__main__":
     test_median_filter()
     test_crop_resize_field()
     test_rotate_field()
+    test_flip_field()
     test_colormap_adjust()
     test_edge_detect()
     test_fft_filter_1d()