geom3

What is it?

geom3 is a rust library for dealing with 3D basic geometric calculations, such as Lines (Rays), Spheres or Planes (Triangles will be available soon). Its the perfect toolset if you plan to start your own raytracer.

What does it do?

You can create/operate with 3D geometric shapes, and calculate intersections, reflections, etc It uses vector3 project for managing 3d vectors (https://docs.rs/crate/vector3/latest)

How do I get started?

Make sure you have a project set up using cargo then:

cargo add geom3

Changelog

• 1.0.1: Breaking changes: changed interface to get input parameters as references instead of values
• 1.0.2: Better documentation

Pending:

• Documentation with explanation of formulas in all functions
• Triangle3 class (with barycentric coordinates support)

Examples:

geom3 uses the vectorial form of the line to calculate intersections. It will calculate only the lambda of each intersection.

let sphere = Sphere::new(&Vector3::new(0.0, 0.0, 0.0), 2.0);
let line = Line3::new(&Vector3::new(0.0, 0.0, 0.0), &Vector3::new(0.0, 0.0, 10.0));
let instersection: List::<f64> = sphere.intersects(&line);
for (_i, &lambda) in instersection.iter().enumerate() {
     let point = line.calc_point(lambda);
}

This provides:

• Better performace: If you just want to know if there is intersection, It will be faster
• If you need the point of each intersection, you can easily calculate it with the calc_point function of the Line3.
• More flexibility: if you want not only to know if it intersects, but also if it intersects "behind" or "beyond" the line director vector, you can easily do it checking if lambda is negative or higher than 1.0

Please, take a look to the unittests for more examples