nalgebra/src/geometry/transform_construction.rs

75 lines
2.0 KiB
Rust

use num::One;
use simba::scalar::RealField;
use crate::base::allocator::Allocator;
use crate::base::dimension::{DimNameAdd, DimNameSum, U1};
use crate::base::{Const, DefaultAllocator, OMatrix};
use crate::geometry::{TCategory, Transform};
impl<T: RealField, C: TCategory, const D: usize> Default for Transform<T, C, D>
where
Const<D>: DimNameAdd<U1>,
DefaultAllocator: Allocator<T, DimNameSum<Const<D>, U1>, DimNameSum<Const<D>, U1>>,
{
fn default() -> Self {
Self::identity()
}
}
impl<T: RealField, C: TCategory, const D: usize> Transform<T, C, D>
where
Const<D>: DimNameAdd<U1>,
DefaultAllocator: Allocator<T, DimNameSum<Const<D>, U1>, DimNameSum<Const<D>, U1>>,
{
/// Creates a new identity transform.
///
/// # Example
///
/// ```
/// # use nalgebra::{Transform2, Projective2, Affine2, Transform3, Projective3, Affine3, Point2, Point3};
///
/// let pt = Point2::new(1.0, 2.0);
/// let t = Projective2::identity();
/// assert_eq!(t * pt, pt);
///
/// let aff = Affine2::identity();
/// assert_eq!(aff * pt, pt);
///
/// let aff = Transform2::identity();
/// assert_eq!(aff * pt, pt);
///
/// // Also works in 3D.
/// let pt = Point3::new(1.0, 2.0, 3.0);
/// let t = Projective3::identity();
/// assert_eq!(t * pt, pt);
///
/// let aff = Affine3::identity();
/// assert_eq!(aff * pt, pt);
///
/// let aff = Transform3::identity();
/// assert_eq!(aff * pt, pt);
/// ```
#[inline]
pub fn identity() -> Self {
Self::from_matrix_unchecked(OMatrix::<
_,
DimNameSum<Const<D>, U1>,
DimNameSum<Const<D>, U1>,
>::identity())
}
}
impl<T: RealField, C: TCategory, const D: usize> One for Transform<T, C, D>
where
Const<D>: DimNameAdd<U1>,
DefaultAllocator: Allocator<T, DimNameSum<Const<D>, U1>, DimNameSum<Const<D>, U1>>,
{
/// Creates a new identity transform.
#[inline]
fn one() -> Self {
Self::identity()
}
}