tip modelling and deconvolution

backend/nodes/field_arithmetic.py

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+from __future__ import annotations
+
+import numpy as np
+
+from backend.node_registry import register_node
+from backend.data_types import DataField
+
+
+@register_node(display_name="Field Arithmetic")
+class FieldArithmetic:
+    @classmethod
+    def INPUT_TYPES(cls):
+        return {
+            "required": {
+                "field_a": ("DATA_FIELD",),
+                "field_b": ("DATA_FIELD",),
+                "operation": (["add", "subtract", "multiply", "divide", "min", "max", "hypot"],),
+            }
+        }
+
+    OUTPUTS = (
+        ('DATA_FIELD', 'result'),
+    )
+    FUNCTION = "process"
+
+    DESCRIPTION = (
+        "Apply a point-wise arithmetic operation to two DATA_FIELDs of the same resolution. "
+        "add/subtract/multiply/divide/min/max perform element-wise operations; "
+        "hypot computes sqrt(a² + b²) per pixel. "
+        "Equivalent to gwy_data_field_sum_fields / subtract_fields / multiply_fields / "
+        "divide_fields / min_of_fields / max_of_fields / hypot_of_fields in arithmetic.c."
+    )
+
+    def process(self, field_a: DataField, field_b: DataField, operation: str) -> tuple:
+        if field_a.data.shape != field_b.data.shape:
+            raise ValueError(
+                f"Fields must have the same resolution: "
+                f"{field_a.data.shape} vs {field_b.data.shape}"
+            )
+
+        a = field_a.data
+        b = field_b.data
+
+        if operation == "add":
+            result = a + b
+        elif operation == "subtract":
+            result = a - b
+        elif operation == "multiply":
+            result = a * b
+        elif operation == "divide":
+            result = a / b
+        elif operation == "min":
+            result = np.minimum(a, b)
+        elif operation == "max":
+            result = np.maximum(a, b)
+        elif operation == "hypot":
+            result = np.hypot(a, b)
+        else:
+            raise ValueError(f"Unknown operation: {operation!r}")
+
+        return (field_a.replace(data=result),)