Struct Triangle 

pub struct Triangle { /* private fields */ }

A constructed 2D triangle represented by three vertices.

Use Triangle::try_new when the vertices come from user input, files, or other external sources. Use Triangle::new when the points are already trusted.

Examples

use use_geometry::{
    Orientation2, Point2, Triangle, triangle_area,
    triangle_twice_signed_area,
};

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 triangle = Triangle::try_new(a, b, c)?;

assert_eq!(triangle.orientation(), Orientation2::CounterClockwise);
assert_eq!(triangle.twice_signed_area(), triangle_twice_signed_area(a, b, c));
assert_eq!(triangle.area(), triangle_area(a, b, c));
assert_eq!(triangle.sides(), [4.0, 5.0, 3.0]);

Implementations

impl Triangle

pub const fn new(a: Point2, b: Point2, c: Point2) -> Self

Creates a triangle from three points.

pub fn try_new(a: Point2, b: Point2, c: Point2) -> Result<Self, GeometryError>

Creates a triangle from three points with finite coordinates.

Use this constructor at API boundaries where coordinates may still need validation. Triangle::new remains available for already-validated points.

Errors

Returns GeometryError::NonFiniteComponent when any vertex contains a non-finite coordinate.

Examples

use use_geometry::{Point2, Triangle};

let triangle = Triangle::try_new(
    Point2::try_new(0.0, 0.0)?,
    Point2::try_new(4.0, 0.0)?,
    Point2::try_new(0.0, 3.0)?,
)?;

assert_eq!(triangle.area(), 6.0);

pub const fn a(self) -> Point2

Returns the first vertex.

pub const fn b(self) -> Point2

Returns the second vertex.

pub const fn c(self) -> Point2

Returns the third vertex.

pub const fn vertices(self) -> [Point2; 3]

Returns the triangle vertices in [a, b, c] order.

pub fn twice_signed_area(self) -> f64

Returns twice the signed area of the triangle.

The sign depends on the vertex winding order.

pub fn twice_area(self) -> f64

Returns twice the unsigned area of the triangle.

pub fn orientation(self) -> Orientation2

Returns the triangle orientation implied by the vertex winding order.

pub fn area(self) -> f64

Returns the triangle area.

pub fn sides(self) -> [f64; 3]

Returns the triangle side lengths in [ab, bc, ca] order.

pub fn perimeter(self) -> f64

Returns the triangle perimeter.

pub fn centroid(self) -> Point2

Returns the triangle centroid.

pub fn is_degenerate(self) -> bool

Returns true when the triangle is exactly degenerate.

Exact degeneracy means the signed twice-area is exactly zero, which in turn means the vertices are collinear.

pub fn is_degenerate_with_tolerance( self, tolerance: f64, ) -> Result<bool, GeometryError>

Returns true when the triangle’s unsigned twice-area is within tolerance of zero.

Use this when you care about practical collapse in measured or generated geometry rather than exact arithmetic collapse.

Errors

Returns GeometryError::NonFiniteTolerance when tolerance is NaN or infinite.

Returns GeometryError::NegativeTolerance when tolerance is negative.

pub const fn aabb(self) -> Aabb2

Returns the triangle bounding box.

Trait Implementations

impl Clone for Triangle

fn clone(&self) -> Triangle

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Triangle

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for Triangle

fn eq(&self, other: &Triangle) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Triangle

impl StructuralPartialEq for Triangle