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author | shumkovnd <shumkovnd@yandex-team.com> | 2023-11-10 14:39:34 +0300 |
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committer | shumkovnd <shumkovnd@yandex-team.com> | 2023-11-10 16:42:24 +0300 |
commit | 77eb2d3fdcec5c978c64e025ced2764c57c00285 (patch) | |
tree | c51edb0748ca8d4a08d7c7323312c27ba1a8b79a /contrib/python/fonttools/fontTools/misc/transform.py | |
parent | dd6d20cadb65582270ac23f4b3b14ae189704b9d (diff) | |
download | ydb-77eb2d3fdcec5c978c64e025ced2764c57c00285.tar.gz |
KIKIMR-19287: add task_stats_drawing script
Diffstat (limited to 'contrib/python/fonttools/fontTools/misc/transform.py')
-rw-r--r-- | contrib/python/fonttools/fontTools/misc/transform.py | 495 |
1 files changed, 495 insertions, 0 deletions
diff --git a/contrib/python/fonttools/fontTools/misc/transform.py b/contrib/python/fonttools/fontTools/misc/transform.py new file mode 100644 index 00000000000..f85b54b7312 --- /dev/null +++ b/contrib/python/fonttools/fontTools/misc/transform.py @@ -0,0 +1,495 @@ +"""Affine 2D transformation matrix class. + +The Transform class implements various transformation matrix operations, +both on the matrix itself, as well as on 2D coordinates. + +Transform instances are effectively immutable: all methods that operate on the +transformation itself always return a new instance. This has as the +interesting side effect that Transform instances are hashable, ie. they can be +used as dictionary keys. + +This module exports the following symbols: + +Transform + this is the main class +Identity + Transform instance set to the identity transformation +Offset + Convenience function that returns a translating transformation +Scale + Convenience function that returns a scaling transformation + +The DecomposedTransform class implements a transformation with separate +translate, rotation, scale, skew, and transformation-center components. + +:Example: + + >>> t = Transform(2, 0, 0, 3, 0, 0) + >>> t.transformPoint((100, 100)) + (200, 300) + >>> t = Scale(2, 3) + >>> t.transformPoint((100, 100)) + (200, 300) + >>> t.transformPoint((0, 0)) + (0, 0) + >>> t = Offset(2, 3) + >>> t.transformPoint((100, 100)) + (102, 103) + >>> t.transformPoint((0, 0)) + (2, 3) + >>> t2 = t.scale(0.5) + >>> t2.transformPoint((100, 100)) + (52.0, 53.0) + >>> import math + >>> t3 = t2.rotate(math.pi / 2) + >>> t3.transformPoint((0, 0)) + (2.0, 3.0) + >>> t3.transformPoint((100, 100)) + (-48.0, 53.0) + >>> t = Identity.scale(0.5).translate(100, 200).skew(0.1, 0.2) + >>> t.transformPoints([(0, 0), (1, 1), (100, 100)]) + [(50.0, 100.0), (50.550167336042726, 100.60135501775433), (105.01673360427253, 160.13550177543362)] + >>> +""" + +import math +from typing import NamedTuple +from dataclasses import dataclass + + +__all__ = ["Transform", "Identity", "Offset", "Scale", "DecomposedTransform"] + + +_EPSILON = 1e-15 +_ONE_EPSILON = 1 - _EPSILON +_MINUS_ONE_EPSILON = -1 + _EPSILON + + +def _normSinCos(v): + if abs(v) < _EPSILON: + v = 0 + elif v > _ONE_EPSILON: + v = 1 + elif v < _MINUS_ONE_EPSILON: + v = -1 + return v + + +class Transform(NamedTuple): + + """2x2 transformation matrix plus offset, a.k.a. Affine transform. + Transform instances are immutable: all transforming methods, eg. + rotate(), return a new Transform instance. + + :Example: + + >>> t = Transform() + >>> t + <Transform [1 0 0 1 0 0]> + >>> t.scale(2) + <Transform [2 0 0 2 0 0]> + >>> t.scale(2.5, 5.5) + <Transform [2.5 0 0 5.5 0 0]> + >>> + >>> t.scale(2, 3).transformPoint((100, 100)) + (200, 300) + + Transform's constructor takes six arguments, all of which are + optional, and can be used as keyword arguments:: + + >>> Transform(12) + <Transform [12 0 0 1 0 0]> + >>> Transform(dx=12) + <Transform [1 0 0 1 12 0]> + >>> Transform(yx=12) + <Transform [1 0 12 1 0 0]> + + Transform instances also behave like sequences of length 6:: + + >>> len(Identity) + 6 + >>> list(Identity) + [1, 0, 0, 1, 0, 0] + >>> tuple(Identity) + (1, 0, 0, 1, 0, 0) + + Transform instances are comparable:: + + >>> t1 = Identity.scale(2, 3).translate(4, 6) + >>> t2 = Identity.translate(8, 18).scale(2, 3) + >>> t1 == t2 + 1 + + But beware of floating point rounding errors:: + + >>> t1 = Identity.scale(0.2, 0.3).translate(0.4, 0.6) + >>> t2 = Identity.translate(0.08, 0.18).scale(0.2, 0.3) + >>> t1 + <Transform [0.2 0 0 0.3 0.08 0.18]> + >>> t2 + <Transform [0.2 0 0 0.3 0.08 0.18]> + >>> t1 == t2 + 0 + + Transform instances are hashable, meaning you can use them as + keys in dictionaries:: + + >>> d = {Scale(12, 13): None} + >>> d + {<Transform [12 0 0 13 0 0]>: None} + + But again, beware of floating point rounding errors:: + + >>> t1 = Identity.scale(0.2, 0.3).translate(0.4, 0.6) + >>> t2 = Identity.translate(0.08, 0.18).scale(0.2, 0.3) + >>> t1 + <Transform [0.2 0 0 0.3 0.08 0.18]> + >>> t2 + <Transform [0.2 0 0 0.3 0.08 0.18]> + >>> d = {t1: None} + >>> d + {<Transform [0.2 0 0 0.3 0.08 0.18]>: None} + >>> d[t2] + Traceback (most recent call last): + File "<stdin>", line 1, in ? + KeyError: <Transform [0.2 0 0 0.3 0.08 0.18]> + """ + + xx: float = 1 + xy: float = 0 + yx: float = 0 + yy: float = 1 + dx: float = 0 + dy: float = 0 + + def transformPoint(self, p): + """Transform a point. + + :Example: + + >>> t = Transform() + >>> t = t.scale(2.5, 5.5) + >>> t.transformPoint((100, 100)) + (250.0, 550.0) + """ + (x, y) = p + xx, xy, yx, yy, dx, dy = self + return (xx * x + yx * y + dx, xy * x + yy * y + dy) + + def transformPoints(self, points): + """Transform a list of points. + + :Example: + + >>> t = Scale(2, 3) + >>> t.transformPoints([(0, 0), (0, 100), (100, 100), (100, 0)]) + [(0, 0), (0, 300), (200, 300), (200, 0)] + >>> + """ + xx, xy, yx, yy, dx, dy = self + return [(xx * x + yx * y + dx, xy * x + yy * y + dy) for x, y in points] + + def transformVector(self, v): + """Transform an (dx, dy) vector, treating translation as zero. + + :Example: + + >>> t = Transform(2, 0, 0, 2, 10, 20) + >>> t.transformVector((3, -4)) + (6, -8) + >>> + """ + (dx, dy) = v + xx, xy, yx, yy = self[:4] + return (xx * dx + yx * dy, xy * dx + yy * dy) + + def transformVectors(self, vectors): + """Transform a list of (dx, dy) vector, treating translation as zero. + + :Example: + >>> t = Transform(2, 0, 0, 2, 10, 20) + >>> t.transformVectors([(3, -4), (5, -6)]) + [(6, -8), (10, -12)] + >>> + """ + xx, xy, yx, yy = self[:4] + return [(xx * dx + yx * dy, xy * dx + yy * dy) for dx, dy in vectors] + + def translate(self, x=0, y=0): + """Return a new transformation, translated (offset) by x, y. + + :Example: + >>> t = Transform() + >>> t.translate(20, 30) + <Transform [1 0 0 1 20 30]> + >>> + """ + return self.transform((1, 0, 0, 1, x, y)) + + def scale(self, x=1, y=None): + """Return a new transformation, scaled by x, y. The 'y' argument + may be None, which implies to use the x value for y as well. + + :Example: + >>> t = Transform() + >>> t.scale(5) + <Transform [5 0 0 5 0 0]> + >>> t.scale(5, 6) + <Transform [5 0 0 6 0 0]> + >>> + """ + if y is None: + y = x + return self.transform((x, 0, 0, y, 0, 0)) + + def rotate(self, angle): + """Return a new transformation, rotated by 'angle' (radians). + + :Example: + >>> import math + >>> t = Transform() + >>> t.rotate(math.pi / 2) + <Transform [0 1 -1 0 0 0]> + >>> + """ + import math + + c = _normSinCos(math.cos(angle)) + s = _normSinCos(math.sin(angle)) + return self.transform((c, s, -s, c, 0, 0)) + + def skew(self, x=0, y=0): + """Return a new transformation, skewed by x and y. + + :Example: + >>> import math + >>> t = Transform() + >>> t.skew(math.pi / 4) + <Transform [1 0 1 1 0 0]> + >>> + """ + import math + + return self.transform((1, math.tan(y), math.tan(x), 1, 0, 0)) + + def transform(self, other): + """Return a new transformation, transformed by another + transformation. + + :Example: + >>> t = Transform(2, 0, 0, 3, 1, 6) + >>> t.transform((4, 3, 2, 1, 5, 6)) + <Transform [8 9 4 3 11 24]> + >>> + """ + xx1, xy1, yx1, yy1, dx1, dy1 = other + xx2, xy2, yx2, yy2, dx2, dy2 = self + return self.__class__( + xx1 * xx2 + xy1 * yx2, + xx1 * xy2 + xy1 * yy2, + yx1 * xx2 + yy1 * yx2, + yx1 * xy2 + yy1 * yy2, + xx2 * dx1 + yx2 * dy1 + dx2, + xy2 * dx1 + yy2 * dy1 + dy2, + ) + + def reverseTransform(self, other): + """Return a new transformation, which is the other transformation + transformed by self. self.reverseTransform(other) is equivalent to + other.transform(self). + + :Example: + >>> t = Transform(2, 0, 0, 3, 1, 6) + >>> t.reverseTransform((4, 3, 2, 1, 5, 6)) + <Transform [8 6 6 3 21 15]> + >>> Transform(4, 3, 2, 1, 5, 6).transform((2, 0, 0, 3, 1, 6)) + <Transform [8 6 6 3 21 15]> + >>> + """ + xx1, xy1, yx1, yy1, dx1, dy1 = self + xx2, xy2, yx2, yy2, dx2, dy2 = other + return self.__class__( + xx1 * xx2 + xy1 * yx2, + xx1 * xy2 + xy1 * yy2, + yx1 * xx2 + yy1 * yx2, + yx1 * xy2 + yy1 * yy2, + xx2 * dx1 + yx2 * dy1 + dx2, + xy2 * dx1 + yy2 * dy1 + dy2, + ) + + def inverse(self): + """Return the inverse transformation. + + :Example: + >>> t = Identity.translate(2, 3).scale(4, 5) + >>> t.transformPoint((10, 20)) + (42, 103) + >>> it = t.inverse() + >>> it.transformPoint((42, 103)) + (10.0, 20.0) + >>> + """ + if self == Identity: + return self + xx, xy, yx, yy, dx, dy = self + det = xx * yy - yx * xy + xx, xy, yx, yy = yy / det, -xy / det, -yx / det, xx / det + dx, dy = -xx * dx - yx * dy, -xy * dx - yy * dy + return self.__class__(xx, xy, yx, yy, dx, dy) + + def toPS(self): + """Return a PostScript representation + + :Example: + + >>> t = Identity.scale(2, 3).translate(4, 5) + >>> t.toPS() + '[2 0 0 3 8 15]' + >>> + """ + return "[%s %s %s %s %s %s]" % self + + def toDecomposed(self) -> "DecomposedTransform": + """Decompose into a DecomposedTransform.""" + return DecomposedTransform.fromTransform(self) + + def __bool__(self): + """Returns True if transform is not identity, False otherwise. + + :Example: + + >>> bool(Identity) + False + >>> bool(Transform()) + False + >>> bool(Scale(1.)) + False + >>> bool(Scale(2)) + True + >>> bool(Offset()) + False + >>> bool(Offset(0)) + False + >>> bool(Offset(2)) + True + """ + return self != Identity + + def __repr__(self): + return "<%s [%g %g %g %g %g %g]>" % ((self.__class__.__name__,) + self) + + +Identity = Transform() + + +def Offset(x=0, y=0): + """Return the identity transformation offset by x, y. + + :Example: + >>> Offset(2, 3) + <Transform [1 0 0 1 2 3]> + >>> + """ + return Transform(1, 0, 0, 1, x, y) + + +def Scale(x, y=None): + """Return the identity transformation scaled by x, y. The 'y' argument + may be None, which implies to use the x value for y as well. + + :Example: + >>> Scale(2, 3) + <Transform [2 0 0 3 0 0]> + >>> + """ + if y is None: + y = x + return Transform(x, 0, 0, y, 0, 0) + + +@dataclass +class DecomposedTransform: + """The DecomposedTransform class implements a transformation with separate + translate, rotation, scale, skew, and transformation-center components. + """ + + translateX: float = 0 + translateY: float = 0 + rotation: float = 0 # in degrees, counter-clockwise + scaleX: float = 1 + scaleY: float = 1 + skewX: float = 0 # in degrees, clockwise + skewY: float = 0 # in degrees, counter-clockwise + tCenterX: float = 0 + tCenterY: float = 0 + + @classmethod + def fromTransform(self, transform): + # Adapted from an answer on + # https://math.stackexchange.com/questions/13150/extracting-rotation-scale-values-from-2d-transformation-matrix + a, b, c, d, x, y = transform + + sx = math.copysign(1, a) + if sx < 0: + a *= sx + b *= sx + + delta = a * d - b * c + + rotation = 0 + scaleX = scaleY = 0 + skewX = skewY = 0 + + # Apply the QR-like decomposition. + if a != 0 or b != 0: + r = math.sqrt(a * a + b * b) + rotation = math.acos(a / r) if b >= 0 else -math.acos(a / r) + scaleX, scaleY = (r, delta / r) + skewX, skewY = (math.atan((a * c + b * d) / (r * r)), 0) + elif c != 0 or d != 0: + s = math.sqrt(c * c + d * d) + rotation = math.pi / 2 - ( + math.acos(-c / s) if d >= 0 else -math.acos(c / s) + ) + scaleX, scaleY = (delta / s, s) + skewX, skewY = (0, math.atan((a * c + b * d) / (s * s))) + else: + # a = b = c = d = 0 + pass + + return DecomposedTransform( + x, + y, + math.degrees(rotation), + scaleX * sx, + scaleY, + math.degrees(skewX) * sx, + math.degrees(skewY), + 0, + 0, + ) + + def toTransform(self): + """Return the Transform() equivalent of this transformation. + + :Example: + >>> DecomposedTransform(scaleX=2, scaleY=2).toTransform() + <Transform [2 0 0 2 0 0]> + >>> + """ + t = Transform() + t = t.translate( + self.translateX + self.tCenterX, self.translateY + self.tCenterY + ) + t = t.rotate(math.radians(self.rotation)) + t = t.scale(self.scaleX, self.scaleY) + t = t.skew(math.radians(self.skewX), math.radians(self.skewY)) + t = t.translate(-self.tCenterX, -self.tCenterY) + return t + + +if __name__ == "__main__": + import sys + import doctest + + sys.exit(doctest.testmod().failed) |