adding more nodes

tests/node_tests/shade.py

@@ -0,0 +1,36 @@
+import numpy as np
+import pytest
+from tests.node_tests._shared import make_field
+
+
+def test_output_shape():
+    """Output shape should match input shape."""
+    from backend.nodes.shade import Shade
+
+    node = Shade()
+    field = make_field(shape=(64, 64))
+    result, = node.process(field, azimuth=315.0, elevation=45.0, blend=0.5)
+    assert result.data.shape == field.data.shape
+
+
+def test_output_range():
+    """With blend=1.0, output values should be in [0, 1]."""
+    from backend.nodes.shade import Shade
+
+    node = Shade()
+    field = make_field(shape=(64, 64))
+    result, = node.process(field, azimuth=315.0, elevation=45.0, blend=1.0)
+    assert result.data.min() >= 0.0 - 1e-12
+    assert result.data.max() <= 1.0 + 1e-12
+
+
+def test_flat_surface():
+    """A flat (constant) surface should produce uniform-ish shading output."""
+    from backend.nodes.shade import Shade
+
+    node = Shade()
+    data = np.ones((64, 64), dtype=np.float64) * 5.0
+    field = make_field(data=data)
+    result, = node.process(field, azimuth=315.0, elevation=45.0, blend=1.0)
+    # Flat surface -> all surface normals point straight up -> uniform shading
+    assert np.std(result.data) < 1e-10