xref: /aosp_15_r20/external/fonttools/Lib/fontTools/misc/vector.py (revision e1fe3e4ad2793916b15cccdc4a7da52a7e1dd0e9)
1from numbers import Number
2import math
3import operator
4import warnings
5
6
7__all__ = ["Vector"]
8
9
10class Vector(tuple):
11    """A math-like vector.
12
13    Represents an n-dimensional numeric vector. ``Vector`` objects support
14    vector addition and subtraction, scalar multiplication and division,
15    negation, rounding, and comparison tests.
16    """
17
18    __slots__ = ()
19
20    def __new__(cls, values, keep=False):
21        if keep is not False:
22            warnings.warn(
23                "the 'keep' argument has been deprecated",
24                DeprecationWarning,
25            )
26        if type(values) == Vector:
27            # No need to create a new object
28            return values
29        return super().__new__(cls, values)
30
31    def __repr__(self):
32        return f"{self.__class__.__name__}({super().__repr__()})"
33
34    def _vectorOp(self, other, op):
35        if isinstance(other, Vector):
36            assert len(self) == len(other)
37            return self.__class__(op(a, b) for a, b in zip(self, other))
38        if isinstance(other, Number):
39            return self.__class__(op(v, other) for v in self)
40        raise NotImplementedError()
41
42    def _scalarOp(self, other, op):
43        if isinstance(other, Number):
44            return self.__class__(op(v, other) for v in self)
45        raise NotImplementedError()
46
47    def _unaryOp(self, op):
48        return self.__class__(op(v) for v in self)
49
50    def __add__(self, other):
51        return self._vectorOp(other, operator.add)
52
53    __radd__ = __add__
54
55    def __sub__(self, other):
56        return self._vectorOp(other, operator.sub)
57
58    def __rsub__(self, other):
59        return self._vectorOp(other, _operator_rsub)
60
61    def __mul__(self, other):
62        return self._scalarOp(other, operator.mul)
63
64    __rmul__ = __mul__
65
66    def __truediv__(self, other):
67        return self._scalarOp(other, operator.truediv)
68
69    def __rtruediv__(self, other):
70        return self._scalarOp(other, _operator_rtruediv)
71
72    def __pos__(self):
73        return self._unaryOp(operator.pos)
74
75    def __neg__(self):
76        return self._unaryOp(operator.neg)
77
78    def __round__(self, *, round=round):
79        return self._unaryOp(round)
80
81    def __eq__(self, other):
82        if isinstance(other, list):
83            # bw compat Vector([1, 2, 3]) == [1, 2, 3]
84            other = tuple(other)
85        return super().__eq__(other)
86
87    def __ne__(self, other):
88        return not self.__eq__(other)
89
90    def __bool__(self):
91        return any(self)
92
93    __nonzero__ = __bool__
94
95    def __abs__(self):
96        return math.sqrt(sum(x * x for x in self))
97
98    def length(self):
99        """Return the length of the vector. Equivalent to abs(vector)."""
100        return abs(self)
101
102    def normalized(self):
103        """Return the normalized vector of the vector."""
104        return self / abs(self)
105
106    def dot(self, other):
107        """Performs vector dot product, returning the sum of
108        ``a[0] * b[0], a[1] * b[1], ...``"""
109        assert len(self) == len(other)
110        return sum(a * b for a, b in zip(self, other))
111
112    # Deprecated methods/properties
113
114    def toInt(self):
115        warnings.warn(
116            "the 'toInt' method has been deprecated, use round(vector) instead",
117            DeprecationWarning,
118        )
119        return self.__round__()
120
121    @property
122    def values(self):
123        warnings.warn(
124            "the 'values' attribute has been deprecated, use "
125            "the vector object itself instead",
126            DeprecationWarning,
127        )
128        return list(self)
129
130    @values.setter
131    def values(self, values):
132        raise AttributeError(
133            "can't set attribute, the 'values' attribute has been deprecated",
134        )
135
136    def isclose(self, other: "Vector", **kwargs) -> bool:
137        """Return True if the vector is close to another Vector."""
138        assert len(self) == len(other)
139        return all(math.isclose(a, b, **kwargs) for a, b in zip(self, other))
140
141
142def _operator_rsub(a, b):
143    return operator.sub(b, a)
144
145
146def _operator_rtruediv(a, b):
147    return operator.truediv(b, a)
148