low pri features

tests/node_tests/mask_shift.py

@@ -0,0 +1,74 @@
+import numpy as np
+import pytest
+
+
+def _make_mask():
+    """Create a simple test mask: 10x10 block of 255 in a 64x64 field."""
+    mask = np.zeros((64, 64), dtype=np.uint8)
+    mask[10:20, 10:20] = 255
+    return mask
+
+
+def test_output_shape():
+    from backend.nodes.mask_shift import MaskShift
+    node = MaskShift()
+    mask = _make_mask()
+
+    result, = node.process(mask, shift_x=5, shift_y=3, border_mode="zero")
+    assert result.shape == mask.shape
+    assert result.dtype == np.uint8
+
+    result_wrap, = node.process(mask, shift_x=-10, shift_y=7, border_mode="wrap")
+    assert result_wrap.shape == mask.shape
+
+    result_mirror, = node.process(mask, shift_x=2, shift_y=-4, border_mode="mirror")
+    assert result_mirror.shape == mask.shape
+
+
+def test_zero_shift_unchanged():
+    from backend.nodes.mask_shift import MaskShift
+    node = MaskShift()
+    mask = _make_mask()
+
+    result_zero, = node.process(mask, shift_x=0, shift_y=0, border_mode="zero")
+    assert np.array_equal(result_zero, mask)
+
+    result_wrap, = node.process(mask, shift_x=0, shift_y=0, border_mode="wrap")
+    assert np.array_equal(result_wrap, mask)
+
+    result_mirror, = node.process(mask, shift_x=0, shift_y=0, border_mode="mirror")
+    assert np.array_equal(result_mirror, mask)
+
+
+def test_wrap_mode():
+    from backend.nodes.mask_shift import MaskShift
+    node = MaskShift()
+    mask = _make_mask()
+
+    # Shift block right by 60 pixels — the block at cols 10:20 should wrap
+    # and appear at cols 70%64=6 to 80%64=16, spanning the boundary.
+    result, = node.process(mask, shift_x=60, shift_y=0, border_mode="wrap")
+    assert result.dtype == np.uint8
+    # The total number of masked pixels should be preserved in wrap mode
+    assert np.count_nonzero(result) == np.count_nonzero(mask)
+    # Original location should not all still be set
+    # (shift is large enough to move block away from original position)
+    assert not np.array_equal(result, mask)
+
+
+def test_zero_mode_fills():
+    from backend.nodes.mask_shift import MaskShift
+    node = MaskShift()
+    mask = _make_mask()
+
+    # Shift right by 5 — left 5 columns should be zeroed
+    result, = node.process(mask, shift_x=5, shift_y=0, border_mode="zero")
+    assert np.all(result[:, :5] == 0)
+    # Block should now be at cols 15:25, rows 10:20
+    assert np.all(result[10:20, 15:25] == 255)
+
+    # Shift down by 5 — top 5 rows should be zeroed
+    result2, = node.process(mask, shift_x=0, shift_y=5, border_mode="zero")
+    assert np.all(result2[:5, :] == 0)
+    # Block should now be at rows 15:25, cols 10:20
+    assert np.all(result2[15:25, 10:20] == 255)