to_trangulation hang on certain shape

[gordlea]

I've been having an issue where if I try to triangulate the following shape, the code hangs up in the to_trangulation function:

I've created a unit test that reproduces this:

    #[test]
    fn test_crasher4() {
        let shape: Shape<FloatPoint<f32>> = vec![
            vec![
                FloatPoint::<f32>::new(1.0, 1.0),
                FloatPoint::<f32>::new(1.0, 4.0),
                FloatPoint::<f32>::new(2.0, 4.0),
                FloatPoint::<f32>::new(2.0, 3.0),
                FloatPoint::<f32>::new(3.0, 3.0),
                FloatPoint::<f32>::new(3.0, 1.0),
            ]
        ];

        let triangulation = shape.to_triangulation(None, 0.);

        eprintln!("we made it here");
    }

It doesn't seem to matter what FillRule I use, I get the same results. Interestingly, I don't get a crash if I close the shape (end with 1.0, 1.0).

This may be a case of me doing something wrong, but I can't seem to figure it out.

[gordlea]

It seems to hang up in this loop here: https://github.com/iShape-Rust/iTriangle/blob/0.27.4/src/monotone/monotone_layout.rs#L255-L258

[gordlea]

Also, just noticed the same things happens with IntShape triangulation:

    #[test]
    fn test_crasher_int() {
        let int_shape: IntShape = vec![
            vec![
                IntPoint::new(1, 1),
                IntPoint::new(1, 4),
                IntPoint::new(2, 4),
                IntPoint::new(2, 3),
                IntPoint::new(3, 3),
                IntPoint::new(3, 1),
            ]
        ];

     
        let triangulation = int_shape.triangulation();

        eprintln!("we made it here");
    }

[NailxSharipov]

I'm not very proud of this library, as it was originally written 6 years ago and it's time for a rewrite. I don't recommend using it in production yet. But it seems that this bug has already been fixed in the latest version.
Anyway, I added your case to the test dataset.

[gordlea]

Hey, don't sell yourself short, the library works nicely and is well documented, which is more than I can say for most of the other ones out there, having tried them. 😄

I will give the latest version a try and report back.

[gordlea]

Interestingly, when I check out master and run the tests, they pass. In my project, I'm getting failures. I will dig deeper into this.

[gordlea]

Huh, when I check out the i_triangle locally, and include the local version in my workspace using i_triangle = { path = "../iTriangle" }, the tests don't hang. When I use i_triangle = "0.27.4" it hangs.

There doesn't seem to be any new commits since 0.27.4 was released, so I am a little stumped.

[NailxSharipov]

Here is a bug you are looking for. Just double check that your version has this fix.