Crate clipper2

Expand description

clipper2 is a path/polygon clipping and offsetting library that supports operations like difference, inflate, intersect, point-in-polygon, union, xor, simplify.

The create uses the clipper2c-sys crate that in turn is a Rust wrapper around the C++ version of Clipper2.

The crate exposes the Clipper API in two alternative ways until the best version has been figured out.

Through the Path/Paths struct methods:
- Path::inflate
- Path::simplify
- Path::is_point_inside
- Paths::inflate
- Paths::simplify
- Paths::to_clipper_subject returns a Clipper builder struct with the current set of paths as the first subject, and allowing to make boolean operations on several sets of paths in one go.
- Paths::to_clipper_open_subject similar but adds the current set of paths as an open “line” rather than a closed path/polygon.
Via the plain functions:

The Path/Paths structs also thas some transformation methods such as:

Path::translate / Paths::translate for moving a path in by a x/y offset
Path::rotate / Paths::rotate for rotating a path in by x radians
Path::scale / Paths::scale for scaling a path by multiplier

§Examples

use clipper2::*;

let path_a: Paths = vec![(0.2, 0.2), (6.0, 0.2), (6.0, 6.0), (0.2, 6.0)].into();
let path_b: Paths = vec![(5.0, 5.0), (8.0, 5.0), (8.0, 8.0), (5.0, 8.0)].into();

let output: Vec<Vec<(f64, f64)>> = path_a
    .to_clipper_subject()
    .add_clip(path_b)
    .difference(FillRule::default())
    .expect("Failed difference operation")
    .into();

dbg!(output);

Image displaying the result of the difference example

More examples can be found in the examples directory.

Structs§

Bounds: Represents an area from one min and one max Point.
Centi: Scale by 100. This is the default.
Clipper: The Clipper struct used as a builder for applying boolean operations to paths.
Deci: Scale by 10.
Milli: Scale by 1000.
NoSubjects: A state indicating no subjects and no clips.
One: No scaling.
Path: A collection of points.
Paths: A collection of paths.
Point: XY Point with custom scaler.
WithClips: A state indicating one or more subjects and one or more clips.
WithSubjects: A state indicating one or more subjects and no clips.

Enums§

ClipperError: Errors that can occur during clipper operations.
EndType: The EndType enumerator is only needed when offsetting (inflating/shrinking). It isn’t needed for polygon clipping.
FillRule: The Clipper Library supports 4 filling rules: Even-Odd, Non-Zero, Positive and Negative. These rules are base on the winding numbers (see below) of each polygon sub-region, which in turn are based on the orientation of each path. Orientation is determined by the order in which vertices are declared during path construction, and whether these vertices progress roughly clockwise or counter-clockwise.
JoinType: The JoinType enumeration is only needed when offsetting (inflating/shrinking). It isn’t needed for polygon clipping. It specifies how to manage offsetting at convex angled joins. Concave joins will always be offset with a mitered join.
PathError: Path related errors
PointInPolygonResult: The result indicates whether the point is inside, or outside, or on one of the specified polygon’s edges.

Traits§

ClipperState: The state of the Clipper struct.
PointScaler: The point scaling trait allows to choose a multiplier for the point values at compile time.

Functions§