# use-geometry
`use-geometry` is the feature-gated facade crate for the RustUse geometry workspace.
It reexports the focused child crates that make up the set so callers can depend on one crate for
pure geometry primitives, descriptors, notation, validation errors, and direct measurement helpers
while implementation stays split into explicit child crates.
The facade contains only crate-level documentation, public reexports, feature-gated child-crate
namespaces, and the `prelude` module. Many child crates begin with minimal primitives and metadata
rather than full algorithms.
## Taxonomy
| Foundations | `use-coordinate`, `use-dimension`, `use-angle`, `use-point` |
| Affine and Euclidean primitives | `use-bounds`, `use-line`, `use-ray`, `use-segment`, `use-plane`, `use-hyperplane`, `use-circle`, `use-sphere`, `use-hypersphere`, `use-torus` |
| Transformations | `use-transform`, `use-affine`, `use-projection`, `use-reflection`, `use-inversion` |
| Metric and relational geometry | `use-distance`, `use-orientation`, `use-intersection`, `use-containment`, `use-congruence`, `use-similarity`, `use-dihedral` |
| Curves and conics | `use-conic`, `use-curve`, `use-polyline`, `use-bezier`, `use-spline` |
| Surfaces and manifolds | `use-surface`, `use-manifold` |
| Planar regions | `use-triangle`, `use-rectangle`, `use-polygon` |
| Polytopes and solids | `use-simplex`, `use-orthotope`, `use-polytope`, `use-polyhedron`, `use-regular-polytope`, `use-archimedean`, `use-catalan-solid`, `use-johnson-solid` |
| Polytope notation and classification | `use-schlafli`, `use-wythoff`, `use-coxeter`, `use-uniform-polytope` |
| Incidence, projective geometry, and configurations | `use-incidence`, `use-projective`, `use-configuration`, `use-duality` |
| Representations and complexes | `use-mesh`, `use-face`, `use-cell`, `use-geometric-complex` |
| Constructions and decompositions | `use-hull`, `use-triangulation`, `use-tessellation`, `use-voronoi`, `use-delaunay` |
| Folding and unfolding | `use-folding`, `use-crease`, `use-origami`, `use-linkage`, `use-unfolding`, `use-rigid-folding`, `use-polyhedral-net` |
## Installation
```toml
[dependencies]
use-geometry = "0.2.1"
```
The default feature set enables `full`, which reexports every child crate. Disable default features
when you want a smaller facade surface:
```toml
[dependencies]
use-geometry = { version = "0.2.1", default-features = false, features = ["point", "schlafli", "regular-polytope"] }
```
Every child crate has a matching feature name without the `use-` prefix. Hyphenated feature names
use underscore namespace modules, such as `regular-polytope` through `use_geometry::regular_polytope`.
The line feature depends on the `use-line` package while exposing the `use_line` library through
`use_geometry::line`. The complex feature depends on the `use-geometric-complex` package while
exposing the `use_complex` library through `use_geometry::complex`.
## Example
```rust
# #[cfg(feature = "full")]
# fn main() -> Result<(), use_geometry::GeometryError> {
use use_geometry::{
Aabb2, Circle, Line2, Orientation2, Point2, RegularPolytope4, Segment2, Sphere,
Triangle, try_orientation_2d,
};
let a = Point2::try_new(0.0, 0.0)?;
let b = Point2::try_new(4.0, 0.0)?;
let c = Point2::try_new(0.0, 3.0)?;
let segment = Segment2::try_new(a, b)?;
let triangle = Triangle::try_new(a, b, c)?;
let circle = Circle::try_new(a, 3.0)?;
let line = Line2::try_from_points(a, b)?;
let bounds = Aabb2::from_points(a, c);
let sphere = Sphere::new(3.0).expect("valid sphere");
assert_eq!(segment.midpoint(), Point2::new(2.0, 0.0));
assert_eq!(triangle.area(), 6.0);
assert_eq!(try_orientation_2d(a, b, c)?, Orientation2::CounterClockwise);
assert_eq!(sphere.diameter(), 6.0);
assert!(circle.contains_point(Point2::new(0.0, 3.0)));
assert!(line.contains_point(Point2::new(2.0, 0.0)));
assert!(bounds.contains_point(Point2::new(0.0, 1.5)));
assert_eq!(RegularPolytope4::TwentyFourCell.schlafli_symbol().to_string(), "{3, 4, 3}");
# Ok(())
# }
# #[cfg(not(feature = "full"))]
# fn main() {}
```
## Notes
- Root exports are feature-gated reexports from child crates.
- Namespace modules such as `point`, `schlafli`, and `regular_polytope` mirror child crates.
- The prelude reexports the same child crate surface through enabled features.
- Named objects belong inside family crates, not standalone crates.
- `use-vector` remains in the `use-math` workspace and is used directly by child crates that need vector types.
- The `use-geometric-complex` package provides geometric complex and cell-complex vocabulary; the `use-complex` package remains the sibling math complex-number crate.