adding more nodes

tests/node_tests/perspective_correction.py

@@ -0,0 +1,53 @@
+import numpy as np
+import pytest
+from tests.node_tests._shared import make_field
+
+
+def test_identity():
+    """All offsets zero should return output approximately equal to input."""
+    from backend.nodes.perspective_correction import PerspectiveCorrection
+
+    node = PerspectiveCorrection()
+    field = make_field(shape=(64, 64))
+    result, = node.process(
+        field,
+        top_left_x=0.0, top_left_y=0.0,
+        top_right_x=0.0, top_right_y=0.0,
+        bottom_left_x=0.0, bottom_left_y=0.0,
+        bottom_right_x=0.0, bottom_right_y=0.0,
+    )
+    assert result.data.shape == field.data.shape
+    assert np.allclose(result.data, field.data, atol=1e-10)
+
+
+def test_nonzero_offset():
+    """Non-zero offsets should change the data while preserving shape."""
+    from backend.nodes.perspective_correction import PerspectiveCorrection
+
+    node = PerspectiveCorrection()
+    field = make_field(shape=(64, 64))
+    result, = node.process(
+        field,
+        top_left_x=0.05, top_left_y=0.05,
+        top_right_x=-0.05, top_right_y=0.05,
+        bottom_left_x=0.05, bottom_left_y=-0.05,
+        bottom_right_x=-0.05, bottom_right_y=-0.05,
+    )
+    assert result.data.shape == field.data.shape
+    assert not np.allclose(result.data, field.data)
+
+
+def test_output_shape():
+    """Output shape must match input shape."""
+    from backend.nodes.perspective_correction import PerspectiveCorrection
+
+    node = PerspectiveCorrection()
+    field = make_field(shape=(48, 96))
+    result, = node.process(
+        field,
+        top_left_x=0.1, top_left_y=0.0,
+        top_right_x=0.0, top_right_y=0.0,
+        bottom_left_x=0.0, bottom_left_y=0.0,
+        bottom_right_x=0.0, bottom_right_y=0.0,
+    )
+    assert result.data.shape == (48, 96)