svg.path 4.0.2

Usage

There are four path segment objects, Line, Arc, CubicBezier and QuadraticBezier.`There is also a Path object that acts as a collection of the path segment objects.

All coordinate values for these classes are given as complex values, where the .real part represents the X coordinate, and the .imag part representes the Y coordinate:

>>> from svg.path import Path, Line, Arc, CubicBezier, QuadraticBezier, Close

All of these objects have a .point() function which will return the coordinates of a point on the path, where the point is given as a floating point value where 0.0 is the start of the path and 1.0 is end end.

You can calculate the length of a Path or it’s segments with the .length() function. For CubicBezier and Arc segments this is done by geometric approximation and for this reason may be very slow. You can make it faster by passing in an error option to the method. If you don’t pass in error, it defaults to 1e-12:

>>> CubicBezier(300+100j, 100+100j, 200+200j, 200+300j).length(error=1e-5)
297.2208145656899

CubicBezier and Arc also has a min_depth option that specifies the minimum recursion depth. This is set to 5 by default, resulting in using a minimum of 32 segments for the calculation. Setting it to 0 is a bad idea for CubicBeziers, as they may become approximated to a straight line.

Line.length() and QuadraticBezier.length() also takes these parameters, but they are ignored.

CubicBezier and QuadraticBezier also has is_smooth_from(previous) methods, that check if the segment is a “smooth” segment compared to the given segment.

There is also a parse_path() function that will take an SVG path definition and return a Path object:

>>> from svg.path import parse_path
>>> parse_path('M 100 100 L 300 100')
Path(Move(to=(100+100j)), Line(start=(100+100j), end=(300+100j)))

>>> path = Path(Line(100+100j,300+100j), Line(100+100j,300+100j))
>>> path.append(QuadraticBezier(300+100j, 200+200j, 200+300j))
>>> path[0] = Line(200+100j,300+100j)
>>> del path[1]

>>> path.d()
'M 200,100 L 300,100 Q 200,200 200,300'

>>> path1 = parse_path('M 100 100 L 300 100 L 200 300 z')

>>> path2 = parse_path('M100,100L300,100L200,300z')

>>> path1 == path2
True

>>> path3 = Path(Line(100+100j,300+100j), Line(300+100j, 200+300j), Line(200+300j, 100+100j))

>>> path1 == path2
True

>>> path1.append(QuadraticBezier(300+100j, 200+200j, 200+300j))
>>> len(path1[2:]) == 3
True

>>> wrong = Path(Line(100+100j,200+100j), Close(200+300j, 0))

Future features

• Reversing paths. They should then reasonably be drawn “backwards” meaning each path segment also needs to be reversed.

• Mathematical transformations might make sense.

• Verifying that paths are correct, or protection against creating incorrect paths.

License

This module is under a MIT License.

4.0.2 (2019-11-04)

• A solution for the setup.cfg [Alex Grönholm]

4.0.1 (2019-11-03)

• The pure setup.cfg config didn’t work. All the tests pass fine, but when installing the package somewhere else, nothing gets installed. So I’m reverting that change for now.

4.0 (2019-11-02)

• Moved all the information from setup.py into setup.cfg.

• Added a Close() command which is different from a Line() command in no way at all, to simplify the handling of closepath commands and subpaths.

• Path()’s no longer have a closed attribute.

• Now fully supports the SVG 1.1 “F.6.2 Out-of-range parameters” list.

• Uses circular maths to calculate the length of circular arcs, more accurate and much faster.

3.1 (2019-10-25)

• The Move null command was not imported into __init__.py [blokhin]

• #41: Switched from pkg_resource-style namespace package for svg to a pkgutil style namespace package.

• A faster point() implementation for paths. [ClayJarCom]

• Dropped support for Python 2.6 and Python 3.3.

• Added support for Python 3.7 and 3.8.

3.0 (2018-08-14)

• Dropped support for Python 3.1 and 3.2. It still works, but it may stop. Added support for Python 3.6. Dropped support for Jython, it’s not supported by Travis, and hasn’t seen a release in over a year.

• #33: Move commands are now preserved when parsed.

• Subpaths are no longer merged even if they are joined.

• #30: Arcs where the endpoint is the same as the start point caused a crash. The SVG specs say that it instead should be the equavalent of skipping that section, which now is the case.

2.2 (2016-10-15)

• Don’t add a line when closing a path if it’s not needed.

2.1.1 (2016-02-28)

• #18: QuadraticBeziers could get a DivideByZero error under certain circumstances. [MTician]

• Accept an error parameter to Path.point() to be able to control error vs performance setting. [saschwarz]

• #25: Arc’s could create a MathDomain error under certain circumstances.

• #17: Set last_command always.

2.0.1 (2015-10-17)

• #20: The doctext for the closed() setter was incorrect.

• #19: Fixed so tests didn’t use relative paths. [danstender]

2.0 (2015-05-15)

• Nothing changed yet.

2.0b1 (2014-11-06)

• Added a Path.d() function to generate the Path’s d attribute.

• Added is_smooth_from() on QubicBezier and QuadradicBezier.

• Path()’s now have a .closed property.

• Fixed the representation so it’s parseable.

• The calculations for CubicBezier and Arc segments are now recursive, and will end when a specific accuracy has been achieved. This is somewhat faster for Arcs and somewhat slower for CubicBezier. However, you can now specify an accuracy, so if you want faster but looser calculations, you can have that.

• ‘t’ segments (smooth, relative QuadraticBeziers) whose previous segment was not a QuadraticBezier would get an incorrect control point.

1.2 (2014-11-01)

• New Quadradic Bezier implementation. [Justin Gruenberg]

• Solved issue #6: Z close path behavior. [abcjjy]

1.1 (2013-10-19)

• Floats with negative exponents work again.

• New tokenizer that is around 20 times faster.

1.0 (2013-05-28)

• Solved issue #2: Paths with negative values and no spaces didn’t work. [regebro]

1.0b1 (2013-02-03)

• Original release.