Feature/rotationmutator

scanpointgenerator/mutators/__init__.py

@@ -14,3 +14,4 @@
 ###
 
 from scanpointgenerator.mutators.randomoffsetmutator import RandomOffsetMutator
+from scanpointgenerator.mutators.rotationmutator import RotationMutator

scanpointgenerator/mutators/rotationmutator.py

@@ -0,0 +1,78 @@
+###
+# Copyright (c) 2019 Diamond Light Source Ltd.
+#
+# All rights reserved. This program and the accompanying materials
+# are made available under the terms of the Eclipse Public License v1.0
+# which accompanies this distribution, and is available at
+# http://www.eclipse.org/legal/epl-v10.html
+#
+# Contributors:
+#    Bryan Tester
+#
+###
+
+from annotypes import Anno, Union, Array, Sequence
+from math import cos, sin, pi
+from scanpointgenerator.core import Mutator, Point
+
+with Anno("Axes to apply rotation to, "
+          "in the order the offsets should be applied"):
+    AAxes = Array[str]
+UAxes = Union[AAxes, Sequence[str], str]
+with Anno("Centre of rotation"):
+    ACoR = Array[float]
+UCoR = Union[ACoR, Sequence[float]]
+with Anno("Angle by which to rotate points (in degrees)"):
+    ARotationAngle = float
+
+
+@Mutator.register_subclass("scanpointgenerator:mutator/RotationMutator:1.0")
+class RotationMutator(Mutator):
+    """Mutator to apply a rotation to the points of an ND
+    ScanPointGenerator"""
+
+    def __init__(self, axes, angle, centreOfRotation):
+        # type: (UAxes, ARotationAngle, UCoR) -> None
+        self.angle = ARotationAngle(angle)
+        self.axes = AAxes(axes)
+        self.centreOfRotation = ACoR(centreOfRotation)
+        msg = "Can only rotate in the plane of a pair of orthogonal axes"
+        assert len(self.axes) == 2, msg
+        assert len(self.centreOfRotation) == 2, msg
+
+    def mutate(self, point, idx):
+        rotated = Point()
+        rotated.indexes = point.indexes
+        rotated.lower = point.lower.copy()
+        rotated.upper = point.upper.copy()
+        rotated.duration = point.duration
+        pos = point.positions
+        rotated.positions = pos.copy()
+        i = self.axes[0]
+        j = self.axes[1]
+        i_off = self.centreOfRotation[0]
+        j_off = self.centreOfRotation[1]
+        rad = pi*(self.angle/180.0)  # convert degrees to radians
+        rotated.positions[i] = (cos(rad) * (pos[i] - i_off)
+                                - sin(rad) * (pos[j] - j_off)) + i_off
+        rotated.positions[j] = (cos(rad) * (pos[j] - j_off)
+                                + sin(rad) * (pos[i] - i_off)) + j_off
+        if (i in point.lower and i in point.upper)\
+                or (j in point.lower and j in point.upper):
+            i_low = pos[i]
+            i_up = pos[i]
+            j_up = pos[j]
+            j_low = pos[j]
+            if j in point.lower:
+                j_low = point.lower[j]
+            if j in point.upper:
+                j_up = point.upper[j]
+            if i in point.lower:
+                i_low = point.lower[i]
+            if i in point.upper:
+                i_up = point.upper[i]
+            rotated.upper[i] = (cos(rad) * (i_up - i_off) - sin(rad) * (j_up - j_off)) + i_off
+            rotated.upper[j] = (cos(rad) * (j_up - j_off) + sin(rad) * (i_up - i_off)) + j_off
+            rotated.lower[i] = (cos(rad) * (i_low - i_off) - sin(rad) * (j_low - j_off)) + i_off
+            rotated.lower[j] = (cos(rad) * (j_low - j_off) + sin(rad) * (i_low - i_off)) + j_off
+        return rotated

tests/test_mutators/test_rotationmutator.py

@@ -0,0 +1,227 @@
+import os
+import sys
+sys.path.append(os.path.join(os.path.dirname(__file__), ".."))
+import unittest
+
+from test_util import ScanPointGeneratorTest
+from scanpointgenerator.compat import range_
+from scanpointgenerator.mutators import RotationMutator
+from scanpointgenerator import Point
+
+from pkg_resources import require
+require("mock")
+from mock import MagicMock
+
+float_error_tolerance = 1e-12
+
+def make_point(j,k):
+    pt = Point()
+    pt.indexes = [j, k]
+    if k == 9:
+        pt.positions = {"x": j / 10., "y": k / 10.}
+        pt.lower = {"x": j / 10., "y": (k - 0.5) / 10.}
+        pt.upper = {"x": (j + 0.5) / 10., "y": 0.45}
+    elif k == 0:
+        pt.positions = {"x": j / 10., "y": k / 10.}
+        pt.lower = {"x": (j - 0.5) / 10., "y": 0.45}
+        pt.upper = {"x": j / 10., "y": (k + 0.5) / 10.}
+    else:
+        pt.positions = {"x": j / 10., "y": k / 10.}
+        pt.lower = {"x": j / 10., "y": (k - 0.5) / 10.}
+        pt.upper = {"x": j / 10., "y": (k + 0.5) / 10.}
+    return pt
+
+class RotationMutatorTest(ScanPointGeneratorTest):
+
+    def test_init(self):
+        m = RotationMutator(["x", "y"], 30, [0., 0.])
+        self.assertEqual(30, m.angle)
+
+    def test_init_fails_for_invalid_axes(self):
+        self.assertRaises(AssertionError, RotationMutator, ["x"], 30, [0.])
+        self.assertRaises(AssertionError, RotationMutator, ["x", "y", "z"], 30, [0., 0., 0.])
+
+    def test_mutate_simple(self):
+        def point_gen():
+            for j in range_(10):
+                for k in range_(10):
+                    pt = make_point(j, k)
+                    yield pt
+        m = RotationMutator(["x", "y"], 30, [0., 0.])
+        original = [p for p in point_gen()]
+        mutated = [m.mutate(p, i) for i, p in enumerate(point_gen())]
+        for o, m in zip(original, mutated):
+            op_x, mp_x = o.positions["x"], m.positions["x"]
+            op_y, mp_y = o.positions["y"], m.positions["y"]
+            ou_x, mu_x = o.upper["x"], m.upper["x"]
+            ou_y, mu_y = o.upper["y"], m.upper["y"]
+            ol_x, ml_x = o.lower["x"], m.lower["x"]
+            ol_y, ml_y = o.lower["y"], m.lower["y"]
+            self.assertTrue(abs((op_x**2 + op_y**2) - (mp_x**2 + mp_y**2)) < float_error_tolerance)
+
+        for i in range(len(original) - 1):
+            # check distance between consecutive points is preserved
+            o_step = (original[i + 1].positions["x"] - original[i].positions["x"]) ** 2 + \
+                     (original[i + 1].positions["y"] - original[i].positions["y"]) ** 2
+            m_step = (mutated[i + 1].positions["x"] - mutated[i].positions["x"]) ** 2 + \
+                     (mutated[i + 1].positions["y"] - mutated[i].positions["y"]) ** 2
+            self.assertTrue(abs(o_step - m_step) < float_error_tolerance)
+
+            # check angle between points preserved
+            o_dot = (original[i + 1].positions["x"] * original[i].positions["x"]) + \
+                    (original[i + 1].positions["y"] * original[i].positions["y"])
+            m_dot = (mutated[i + 1].positions["x"] * mutated[i].positions["x"]) + \
+                    (mutated[i + 1].positions["y"] * mutated[i].positions["y"])
+            self.assertTrue(abs(o_dot - m_dot) < float_error_tolerance)
+
+            # check bounds still correct
+            self.assertEqual(original[i + 1].lower["x"], original[i].upper["x"])
+            self.assertEqual(original[i + 1].lower["y"], original[i].upper["y"])
+            self.assertEqual(mutated[i + 1].lower["x"], mutated[i].upper["x"])
+            self.assertEqual(mutated[i + 1].lower["y"], mutated[i].upper["y"])
+
+    def test_mutate_cor(self):
+        def point_gen():
+            for j in range_(10):
+                for k in range_(10):
+                    pt = make_point(j, k)
+                yield pt
+        CoR = [2., 3.]
+        m = RotationMutator(["x", "y"], 30, CoR)
+        original = [p for p in point_gen()]
+        mutated = [m.mutate(p, i) for i, p in enumerate(point_gen())]
+        o_r = []
+        m_r = []
+        o_rel_x = []
+        o_rel_y = []
+        m_rel_x = []
+        m_rel_y = []
+        for o, m in zip(original, mutated):
+            op_x, mp_x = o.positions["x"], m.positions["x"]
+            op_y, mp_y = o.positions["y"], m.positions["y"]
+            ou_x, mu_x = o.upper["x"], m.upper["x"]
+            ou_y, mu_y = o.upper["y"], m.upper["y"]
+            ol_x, ml_x = o.lower["x"], m.lower["x"]
+            ol_y, ml_y = o.lower["y"], m.lower["y"]
+            # self.assertNotEqual(op_x, mp_x)
+            # self.assertNotEqual(op_y, mp_y)
+            o_rel_x += [op_x - CoR[0]]
+            o_rel_y += [op_y - CoR[1]]
+            m_rel_x += [mp_x - CoR[0]]
+            m_rel_y += [mp_y - CoR[1]]
+            o_r += [(op_x - CoR[0]) ** 2 + (op_y - CoR[1]) ** 2]
+            m_r += [(mp_x - CoR[0]) ** 2 + (mp_y - CoR[1]) ** 2]
+
+            self.assertTrue(abs(m_r[-1] - o_r[-1]) < float_error_tolerance)
+
+        for i in range(len(original) - 1):
+            # check distance between consecutive points is preserved
+            o_step = (original[i + 1].positions["x"] - original[i].positions["x"]) ** 2 + \
+                     (original[i + 1].positions["y"] - original[i].positions["y"]) ** 2
+            m_step = (mutated[i + 1].positions["x"] - mutated[i].positions["x"]) ** 2 + \
+                     (mutated[i + 1].positions["y"] - mutated[i].positions["y"]) ** 2
+            self.assertTrue(abs(o_step - m_step) < float_error_tolerance)
+
+            # check angle between points preserved
+            o_dot = (o_rel_x[i + 1] * o_rel_x[i]) + (o_rel_y[i + 1] * o_rel_y[i])
+            m_dot = (m_rel_x[i + 1] * m_rel_x[i]) + (m_rel_y[i + 1] * m_rel_y[i])
+            self.assertTrue(abs(o_dot - m_dot) < float_error_tolerance)
+
+    def test_mutate_90_degrees(self):
+        def point_gen():
+            for j in range_(10):
+                for k in range_(10):
+                    pt = make_point(j, k)
+                yield pt
+        m = RotationMutator(["x", "y"], 90, [0., 0.])
+        original = [p for p in point_gen()]
+        mutated = [m.mutate(p, i) for i, p in enumerate(point_gen())]
+        for o, m in zip(original, mutated):
+            op_x, mp_x = o.positions["x"], m.positions["x"]
+            op_y, mp_y = o.positions["y"], m.positions["y"]
+            ou_x, mu_x = o.upper["x"], m.upper["x"]
+            ou_y, mu_y = o.upper["y"], m.upper["y"]
+            ol_x, ml_x = o.lower["x"], m.lower["x"]
+            ol_y, ml_y = o.lower["y"], m.lower["y"]
+            # self.assertNotEqual(op_x, mp_x)
+            # self.assertNotEqual(op_y, mp_y)
+            self.assertTrue(abs((op_x**2 + op_y**2) - (mp_x**2 + mp_y**2)) < float_error_tolerance)
+            # rotate 90 degrees, mp_y = op_x, mp_x = -op_y
+            self.assertTrue(abs(op_x - mp_y) < float_error_tolerance)
+            self.assertTrue(abs(op_y + mp_x) < float_error_tolerance)
+
+        # check distance between consecutive points is preserved
+        for i in range(len(original) - 1):
+            o_step = (original[i + 1].positions["x"] - original[i].positions["x"]) ** 2 + \
+                     (original[i + 1].positions["y"] - original[i].positions["y"]) ** 2
+            m_step = (mutated[i + 1].positions["x"] - mutated[i].positions["x"]) ** 2 + \
+                     (mutated[i + 1].positions["y"] - mutated[i].positions["y"]) ** 2
+            self.assertTrue(abs(o_step - m_step) < float_error_tolerance)
+
+    def test_mutate_twice_opposite(self):
+        def point_gen():
+            for j in range_(10):
+                for k in range_(10):
+                    pt = make_point(j, k)
+                yield pt
+        m1 = RotationMutator(["x", "y"], 30, [0., 0.])
+        m2 = RotationMutator(["x", "y"], -30, [0., 0.])
+        original = [p for p in point_gen()]
+        mutated1 = [m1.mutate(p, i) for i, p in enumerate(point_gen())]
+        mutated2 = [m2.mutate(p, i) for i, p in enumerate(mutated1)]
+        for o, m in zip(original, mutated2):
+            op_x, mp_x = o.positions["x"], m.positions["x"]
+            op_y, mp_y = o.positions["y"], m.positions["y"]
+            ou_x, mu_x = o.upper["x"], m.upper["x"]
+            ou_y, mu_y = o.upper["y"], m.upper["y"]
+            ol_x, ml_x = o.lower["x"], m.lower["x"]
+            ol_y, ml_y = o.lower["y"], m.lower["y"]
+            # should be equal within floating point error
+            self.assertTrue(abs(mp_x - op_x) < float_error_tolerance)
+            self.assertTrue(abs(mu_x - ou_x) < float_error_tolerance)
+            self.assertTrue(abs(ml_x - ol_x) < float_error_tolerance)
+            self.assertTrue(abs(mp_y - op_y) < float_error_tolerance)
+            self.assertTrue(abs(mu_y - ou_y) < float_error_tolerance)
+            self.assertTrue(abs(ml_y - ol_y) < float_error_tolerance)
+
+
+class TestSerialisation(unittest.TestCase):
+
+    def setUp(self):
+        self.l = MagicMock()
+        self.l_dict = MagicMock()
+        self.centreOfRotation = [0., 0.]
+        self.m = RotationMutator(["x", "y"], 45, self.centreOfRotation)
+
+    def test_to_dict(self):
+        self.l.to_dict.return_value = self.l_dict
+
+        expected_dict = dict()
+        expected_dict['typeid'] = "scanpointgenerator:mutator/RotationMutator:1.0"
+        expected_dict['angle'] = 45
+        expected_dict['axes'] = ["x", "y"]
+        expected_dict['centreOfRotation'] = self.centreOfRotation
+
+        d = self.m.to_dict()
+
+        self.assertEqual(expected_dict, d)
+
+    def test_from_dict(self):
+
+        _dict = dict()
+        _dict['angle'] = 45
+        _dict['axes'] = ["x", "y"]
+        _dict['centreOfRotation'] = self.centreOfRotation
+
+        units_dict = dict()
+        units_dict['x'] = 'mm'
+        units_dict['y'] = 'mm'
+
+        m = RotationMutator.from_dict(_dict)
+
+        self.assertEqual(45, m.angle)
+        self.assertEqual(self.centreOfRotation, m.centreOfRotation)
+
+
+if __name__ == "__main__":
+    unittest.main(verbosity=2)