nvictus / svgpath2mpl

SVG path parser for matplotlib

svgpath2mpl

Parse SVG paths into matplotlib Path objects for plotting.

A path in SVG is defined by a 'path' element which contains a d="(path data)" attribute that contains moveto, line, curve (both cubic and quadratic Béziers), arc and closepath instructions. Matplotlib actually supports all of these instructions natively but doesn't provide a parser or fully compatible API.

Based on:

1. svg_parse for matplotlib by Nicolas P. Rougier (BSD license).
2. svg.path by Lennart Regebro (MIT license).

This module adds the path commands missing from (1), including smooth curves and endpoint-parameterized elliptical arcs.

>>> from svgpath2mpl import parse_path
>>> parse_path('M 100 100 L 300 100')
Path(array([[ 100.,  100.], [ 300.,  100.]]), array([1, 2], dtype=uint8))

See the Jupyter Notebook gallery of examples.

Resources

See the SVG Specification.

See the matplotlib path tutorial and API docs.

License

BSD (3-Clause).

svgpath2mpl's Issues

matplotlib patches.Arc behavior changed

I believe by mpl 2.0, the underlying implementation for extracting path commands from Arc patches no longer works as expected, causing arc commands to no longer render properly. I was working on a replacement back in March, but filing the issue now.

Multiple values per command are not correctly handled.

As per SVG specifications, a command can be followed by more than a set of values, for instance, the M command can be followed by 2n vales, not only by just two values.

Missing portions rendering some shapes

Hello.

I'm trying to render some SVGs like: https://fontawesome.com/icons/ice-cream

But I get some strange behavior, as some areas are ignored. It seems the source path has self-intersections, so I wonder if svgpath2mpl handles them.

The path in that SVG is: {'d': 'M368 160h-.94a144 144 0 1 0-286.12 0H80a48 48 0 0 0 0 96h288a48 48 0 0 0 0-96zM195.38 493.69a31.52 31.52 0 0 0 57.24 0L352 288H96z'}.

Any insight is appreciated.

"Absolute" Horizontal and Vertical lines still need to use one of existing coordinates

In the case of an 'absolute' horizontal line, you still need to use the existing Y value as the new Y value.
In the case of an 'absolute' vertical line, you still need to use the existing X value as the new X value.

This is different from most of the path elements, where "absolute" means that both the X and Y value should be used.

The following path will not be drawn correctly:

<path fill="#FF8080" stroke="#000000" stroke-width="5" d="M173.25,517V327l132-122l132,122v190"/>

This can be fixed by (for example) modifying parse_path as follows:

...
        elif command == 'H':
            # Horizontal line.
            verts = np.r_[values, 0. if is_relative else current_point[1]]
            codes = COMMANDS[command]

        elif command == 'V':
            # Vertical line.
            verts = np.r_[0. if is_relative else current_point[0], values]
            codes = COMMANDS[command]
...

Incorrect parsing of M x,y x,y x,y ...

According to the SVG 1.1 standard, "If a moveto is followed by multiple pairs of coordinates, the subsequent pairs are treated as implicit lineto commands."

svgpath2mpl incorrectly treats these as multiple moveto commands.

For example: 'm 11911.875,5278.5265 1.875,43.125 -322.5,-0.9375 0.938,-46.875 z'

is converted to:

Path(array([[11911.875 , 5278.5265],
[11913.75 , 5321.6515],
[11591.25 , 5320.714 ],
[11592.188 , 5273.839 ]]), array([1, 1, 1, 1], dtype=uint8))

When it should be:

Path(array([[11911.875 , 5278.5265],
[11913.75 , 5321.6515],
[11591.25 , 5320.714 ],
[11592.188 , 5273.839 ]]), array([1, 2, 2, 2], dtype=uint8))