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#[cfg(feature = "arbitrary")]
use quickcheck::{Arbitrary, Gen};
use num::{Bounded, One, Zero};
#[cfg(feature = "rand-no-std")]
use rand::{
Rng,
distr::{Distribution, StandardUniform},
};
use crate::base::allocator::Allocator;
use crate::base::dimension::{DimNameAdd, DimNameSum, U1};
use crate::base::{DefaultAllocator, Scalar};
use crate::{
Const, DimName, OPoint, OVector, Point1, Point2, Point3, Point4, Point5, Point6, Vector1,
Vector2, Vector3, Vector4, Vector5, Vector6,
};
use simba::scalar::{ClosedDivAssign, SupersetOf};
use crate::geometry::Point;
impl<T: Scalar + Zero, D: DimName> Default for OPoint<T, D>
where
DefaultAllocator: Allocator<D>,
{
fn default() -> Self {
Self::origin()
}
}
/// # Other construction methods
impl<T: Scalar, D: DimName> OPoint<T, D>
where
DefaultAllocator: Allocator<D>,
{
/// Creates a new point with all coordinates equal to zero.
///
/// # Example
///
/// ```
/// # use nalgebra::{Point2, Point3};
/// // This works in any dimension.
/// // The explicit crate::<f32> type annotation may not always be needed,
/// // depending on the context of type inference.
/// let pt = Point2::<f32>::origin();
/// assert!(pt.x == 0.0 && pt.y == 0.0);
///
/// let pt = Point3::<f32>::origin();
/// assert!(pt.x == 0.0 && pt.y == 0.0 && pt.z == 0.0);
/// ```
#[inline]
pub fn origin() -> Self
where
T: Zero,
{
Self::from(OVector::from_element(T::zero()))
}
/// Creates a new point from a slice.
///
/// # Example
///
/// ```
/// # use nalgebra::{Point2, Point3};
/// let data = [ 1.0, 2.0, 3.0 ];
///
/// let pt = Point2::from_slice(&data[..2]);
/// assert_eq!(pt, Point2::new(1.0, 2.0));
///
/// let pt = Point3::from_slice(&data);
/// assert_eq!(pt, Point3::new(1.0, 2.0, 3.0));
/// ```
#[inline]
pub fn from_slice(components: &[T]) -> Self {
Self::from(OVector::from_row_slice(components))
}
/// Creates a new point from its homogeneous vector representation.
///
/// In practice, this builds a D-dimensional points with the same first D component as `v`
/// divided by the last component of `v`. Returns `None` if this divisor is zero.
///
/// # Example
///
/// ```
/// # use nalgebra::{Point2, Point3, Vector3, Vector4};
///
/// let coords = Vector4::new(1.0, 2.0, 3.0, 1.0);
/// let pt = Point3::from_homogeneous(coords);
/// assert_eq!(pt, Some(Point3::new(1.0, 2.0, 3.0)));
///
/// // All component of the result will be divided by the
/// // last component of the vector, here 2.0.
/// let coords = Vector4::new(1.0, 2.0, 3.0, 2.0);
/// let pt = Point3::from_homogeneous(coords);
/// assert_eq!(pt, Some(Point3::new(0.5, 1.0, 1.5)));
///
/// // Fails because the last component is zero.
/// let coords = Vector4::new(1.0, 2.0, 3.0, 0.0);
/// let pt = Point3::from_homogeneous(coords);
/// assert!(pt.is_none());
///
/// // Works also in other dimensions.
/// let coords = Vector3::new(1.0, 2.0, 1.0);
/// let pt = Point2::from_homogeneous(coords);
/// assert_eq!(pt, Some(Point2::new(1.0, 2.0)));
/// ```
#[inline]
pub fn from_homogeneous(v: OVector<T, DimNameSum<D, U1>>) -> Option<Self>
where
T: Scalar + Zero + One + ClosedDivAssign,
D: DimNameAdd<U1>,
DefaultAllocator: Allocator<DimNameSum<D, U1>>,
{
if !v[D::DIM].is_zero() {
let coords = v.generic_view((0, 0), (D::name(), Const::<1>)) / v[D::DIM].clone();
Some(Self::from(coords))
} else {
None
}
}
/// Cast the components of `self` to another type.
///
/// # Example
/// ```
/// # use nalgebra::Point2;
/// let pt = Point2::new(1.0f64, 2.0);
/// let pt2 = pt.cast::<f32>();
/// assert_eq!(pt2, Point2::new(1.0f32, 2.0));
/// ```
pub fn cast<To: Scalar>(self) -> OPoint<To, D>
where
OPoint<To, D>: SupersetOf<Self>,
DefaultAllocator: Allocator<D>,
{
crate::convert(self)
}
}
/*
*
* Traits that build points.
*
*/
impl<T: Scalar + Bounded, D: DimName> Bounded for OPoint<T, D>
where
DefaultAllocator: Allocator<D>,
{
#[inline]
fn max_value() -> Self {
Self::from(OVector::max_value())
}
#[inline]
fn min_value() -> Self {
Self::from(OVector::min_value())
}
}
#[cfg(feature = "rand-no-std")]
impl<T: Scalar, D: DimName> Distribution<OPoint<T, D>> for StandardUniform
where
StandardUniform: Distribution<T>,
DefaultAllocator: Allocator<D>,
{
/// Generate a `Point` where each coordinate is an independent variate from `[0, 1)`.
#[inline]
fn sample<'a, G: Rng + ?Sized>(&self, rng: &mut G) -> OPoint<T, D> {
OPoint::from(rng.random::<OVector<T, D>>())
}
}
#[cfg(feature = "arbitrary")]
impl<T: Scalar + Arbitrary + Send, D: DimName> Arbitrary for OPoint<T, D>
where
<DefaultAllocator as Allocator<D>>::Buffer<T>: Send,
DefaultAllocator: Allocator<D>,
{
#[inline]
fn arbitrary(g: &mut Gen) -> Self {
Self::from(OVector::arbitrary(g))
}
}
/*
*
* Small points construction from components.
*
*/
// NOTE: the impl for Point1 is not with the others so that we
// can add a section with the impl block comment.
/// # Construction from individual components
impl<T: Scalar> Point1<T> {
/// Initializes this point from its components.
///
/// # Example
///
/// ```
/// # use nalgebra::Point1;
/// let p = Point1::new(1.0);
/// assert_eq!(p.x, 1.0);
/// ```
#[inline]
pub const fn new(x: T) -> Self {
Point {
coords: Vector1::new(x),
}
}
}
macro_rules! componentwise_constructors_impl(
($($doc: expr_2021; $Point: ident, $Vector: ident, $($args: ident:$irow: expr_2021),*);* $(;)*) => {$(
impl<T: Scalar> $Point<T> {
#[doc = "Initializes this point from its components."]
#[doc = "# Example\n```"]
#[doc = $doc]
#[doc = "```"]
#[inline]
pub const fn new($($args: T),*) -> Self {
Point { coords: $Vector::new($($args),*) }
}
}
)*}
);
componentwise_constructors_impl!(
"# use nalgebra::Point2;\nlet p = Point2::new(1.0, 2.0);\nassert!(p.x == 1.0 && p.y == 2.0);";
Point2, Vector2, x:0, y:1;
"# use nalgebra::Point3;\nlet p = Point3::new(1.0, 2.0, 3.0);\nassert!(p.x == 1.0 && p.y == 2.0 && p.z == 3.0);";
Point3, Vector3, x:0, y:1, z:2;
"# use nalgebra::Point4;\nlet p = Point4::new(1.0, 2.0, 3.0, 4.0);\nassert!(p.x == 1.0 && p.y == 2.0 && p.z == 3.0 && p.w == 4.0);";
Point4, Vector4, x:0, y:1, z:2, w:3;
"# use nalgebra::Point5;\nlet p = Point5::new(1.0, 2.0, 3.0, 4.0, 5.0);\nassert!(p.x == 1.0 && p.y == 2.0 && p.z == 3.0 && p.w == 4.0 && p.a == 5.0);";
Point5, Vector5, x:0, y:1, z:2, w:3, a:4;
"# use nalgebra::Point6;\nlet p = Point6::new(1.0, 2.0, 3.0, 4.0, 5.0, 6.0);\nassert!(p.x == 1.0 && p.y == 2.0 && p.z == 3.0 && p.w == 4.0 && p.a == 5.0 && p.b == 6.0);";
Point6, Vector6, x:0, y:1, z:2, w:3, a:4, b:5;
);