Merge pull request #142 from aepsil0n/vector_cast

Type-cast a vector component-wise

src/aabb.rs

@@ -24,9 +24,9 @@ use point::{Point, Point2, Point3};
 use vector::{Vector, Vector2, Vector3};
 use ray::{Ray2};
 use intersect::Intersect;
-use num::{BaseNum, BaseFloat};
+use num::{zero, one, BaseNum, BaseFloat};
 use std::fmt;
-use std::num::{zero, one, Float};
+use std::num::Float;
 
 pub trait Aabb<S: BaseNum, V: Vector<S>, P: Point<S, V>> {
     /// Create a new AABB using two points as opposing corners.

src/angle.rs

@@ -16,10 +16,10 @@
 //! Angle units for type-safe, self-documenting code.
 
 use std::fmt;
-use std::num::{One, one, Zero, zero, cast, Float};
+use std::num::{cast, Float};
 
 use approx::ApproxEq;
-use num::BaseFloat;
+use num::{BaseFloat, One, one, Zero, zero};
 
 /// An angle, in radians
 #[deriving(Clone, PartialEq, PartialOrd, Hash, Encodable, Decodable, Rand)]

src/cgmath.rs

@@ -77,7 +77,7 @@ pub use obb::{Obb2, Obb3};
 pub use sphere::Sphere;
 
 pub use approx::ApproxEq;
-pub use num::{PartialOrd, BaseNum, BaseInt, BaseFloat};
+pub use num::{BaseNum, BaseInt, BaseFloat, One, one, Zero, zero};
 
 // Modules
 

src/line.rs

@@ -15,9 +15,7 @@
 
 //! Line segments
 
-use std::num::{Zero, zero, One, one};
-
-use num::{BaseNum, BaseFloat};
+use num::{BaseNum, BaseFloat, Zero, zero, One, one};
 use point::{Point, Point2, Point3};
 use vector::{Vector, Vector2};
 use ray::{Ray2};

src/matrix.rs

@@ -17,12 +17,12 @@
 
 use std::fmt;
 use std::mem;
-use std::num::{Zero, zero, One, one, cast};
+use std::num::cast;
 
 use angle::{Rad, sin, cos, sin_cos};
 use approx::ApproxEq;
 use array::{Array1, Array2, FixedArray};
-use num::{BaseFloat, BaseNum};
+use num::{BaseFloat, BaseNum, Zero, zero, One, one};
 use point::{Point, Point3};
 use quaternion::{Quaternion, ToQuaternion};
 use vector::{Vector, EuclideanVector};

src/num.rs

@@ -17,7 +17,7 @@ use approx::ApproxEq;
 
 use std::cmp;
 use std::fmt;
-use std::num::{FloatMath, Int, Primitive};
+use std::num::{FloatMath, Int, NumCast, Float};
 
 /// A trait providing a [partial ordering](http://mathworld.wolfram.com/PartialOrder.html).
 pub trait PartialOrd {
@@ -57,21 +57,90 @@ macro_rules! partial_ord_float (
 partial_ord_float!(f32)
 partial_ord_float!(f64)
 
-/// Base numeric types with partial ordering
-pub trait BaseNum: Primitive + PartialOrd + fmt::Show {}
+/// Additive neutral element
+pub trait Zero {
+    fn zero() -> Self;
+    fn is_zero(&self) -> bool;
+}
+
+/// Multiplicative neutral element
+pub trait One {
+    fn one() -> Self;
+}
+
+/// Base numeric types with partial ordering
+pub trait BaseNum:
+    Copy + NumCast + Clone + Add<Self, Self> + Sub<Self, Self> +
+    Mul<Self, Self> + Div<Self, Self> + Rem<Self, Self> + Neg<Self> + PartialEq
+    + PartialOrd + cmp::PartialOrd + fmt::Show + Zero + One
+{}
+
+
+macro_rules! impl_basenum_int (
+    ($T: ident) => (
+        impl BaseNum for $T {}
+        impl Zero for $T {
+            fn zero() -> $T {
+                Int::zero()
+            }
+
+            fn is_zero(&self) -> bool {
+                *self == Int::zero()
+            }
+        }
+
+        impl One for $T {
+            fn one() -> $T {
+                Int::one()
+            }
+        }
+    )
+)
+
+impl_basenum_int!(i8)
+impl_basenum_int!(i16)
+impl_basenum_int!(i32)
+impl_basenum_int!(i64)
+impl_basenum_int!(u8)
+impl_basenum_int!(u16)
+impl_basenum_int!(u32)
+impl_basenum_int!(u64)
+impl_basenum_int!(int)
+impl_basenum_int!(uint)
+
+
+macro_rules! impl_basenum_float (
+    ($T: ident) => (
+        impl BaseNum for $T {}
+        impl Zero for $T {
+            fn zero() -> $T {
+                Float::zero()
+            }
+
+            fn is_zero(&self) -> bool {
+                *self == Float::zero()
+            }
+        }
+
+        impl One for $T {
+            fn one() -> $T {
+                Float::one()
+            }
+        }
+    )
+)
+
+impl_basenum_float!(f32)
+impl_basenum_float!(f64)
+
+pub fn zero<T: Zero>() -> T {
+    Zero::zero()
+}
+
+pub fn one<T: One>() -> T {
+    One::one()
+}
 
-impl BaseNum for i8 {}
-impl BaseNum for i16 {}
-impl BaseNum for i32 {}
-impl BaseNum for i64 {}
-impl BaseNum for int {}
-impl BaseNum for u8 {}
-impl BaseNum for u16 {}
-impl BaseNum for u32 {}
-impl BaseNum for u64 {}
-impl BaseNum for uint {}
-impl BaseNum for f32 {}
-impl BaseNum for f64 {}
 
 /// Base integer types
 pub trait BaseInt : BaseNum + Int {}

src/plane.rs

@@ -14,11 +14,10 @@
 // limitations under the License.
 
 use std::fmt;
-use std::num::Zero;
 
 use approx::ApproxEq;
 use intersect::Intersect;
-use num::BaseFloat;
+use num::{BaseFloat, Zero, zero};
 use point::{Point, Point3};
 use ray::Ray3;
 use vector::{Vector3, Vector4};
@@ -80,7 +79,7 @@ impl<S: BaseFloat> Plane<S> {
         // find the normal vector that is perpendicular to v1 and v2
         let mut n = v0.cross(&v1);
 
-        if n.approx_eq(&Vector3::zero()) { None }
+        if n.approx_eq(&zero()) { None }
         else {
             // compute the normal and the distance to the plane
             n.normalize_self();

src/point.rs

@@ -19,11 +19,10 @@
 
 use std::fmt;
 use std::mem;
-use std::num::{one, zero};
 
 use approx::ApproxEq;
 use array::{Array1, FixedArray};
-use num::{BaseNum, BaseFloat};
+use num::{BaseNum, BaseFloat, one, zero};
 use vector::*;
 
 /// A point in 2-dimensional space.

src/projection.rs

@@ -13,12 +13,12 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use std::num::{zero, one, cast};
+use std::num::cast;
 
 use angle::{Angle, tan, cot};
 use frustum::Frustum;
 use matrix::{Matrix4, ToMatrix4};
-use num::BaseFloat;
+use num::{BaseFloat, zero, one};
 use plane::Plane;
 
 /// Create a perspective projection matrix.

src/quaternion.rs

@@ -15,13 +15,13 @@
 
 use std::fmt;
 use std::mem;
-use std::num::{zero, one, cast, Float};
+use std::num::{cast, Float};
 
 use angle::{Angle, Rad, acos, sin, sin_cos, rad};
 use approx::ApproxEq;
 use array::Array1;
 use matrix::{Matrix3, ToMatrix3, ToMatrix4, Matrix4};
-use num::BaseFloat;
+use num::{BaseFloat, one, zero};
 use point::Point3;
 use rotation::{Rotation, Rotation3, Basis3, ToBasis3};
 use vector::{Vector3, Vector, EuclideanVector};
@@ -87,7 +87,7 @@ impl<S: BaseFloat> Quaternion<S> {
     /// The multiplicative identity, ie: `q = 1 + 0i + 0j + 0i`
     #[inline]
     pub fn identity() -> Quaternion<S> {
-        Quaternion::from_sv(one::<S>(), Vector3::zero())
+        Quaternion::from_sv(one::<S>(), zero())
     }
 
     /// The result of multiplying the quaternion a scalar

src/sphere.rs

@@ -16,13 +16,11 @@
 //! Bounding sphere
 
 use intersect::Intersect;
-use num::BaseFloat;
+use num::{BaseFloat, zero};
 use point::{Point, Point3};
 use ray::Ray3;
 use vector::Vector;
 
-use std::num::zero;
-
 #[deriving(Clone, PartialEq, Encodable, Decodable)]
 pub struct Sphere<S> {
     pub center: Point3<S>,

src/transform.rs

@@ -13,11 +13,11 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use std::{fmt, num};
+use std::fmt;
 
 use approx::ApproxEq;
 use matrix::{Matrix, Matrix4, ToMatrix4};
-use num::{BaseNum, BaseFloat};
+use num::{BaseNum, BaseFloat, zero, one};
 use point::{Point, Point3};
 use ray::Ray;
 use rotation::{Rotation, Rotation3};
@@ -87,9 +87,9 @@ impl<S: BaseFloat, V: Vector<S>, P: Point<S, V>, R: Rotation<S, V, P>> Transform
     #[inline]
     fn identity() -> Decomposed<S, V, R> {
         Decomposed {
-            scale: num::one(),
+            scale: one(),
             rot: Rotation::identity(),
-            disp: num::zero(),
+            disp: zero(),
         }
     }
 
@@ -99,7 +99,7 @@ impl<S: BaseFloat, V: Vector<S>, P: Point<S, V>, R: Rotation<S, V, P>> Transform
         let rot: R = Rotation::look_at(&center.sub_p(eye), up);
         let disp: V = rot.rotate_vector(&origin.sub_p(eye));
         Decomposed {
-            scale: num::one(),
+            scale: one(),
             rot: rot,
             disp: disp,
         }
@@ -124,10 +124,10 @@ impl<S: BaseFloat, V: Vector<S>, P: Point<S, V>, R: Rotation<S, V, P>> Transform
     }
 
     fn invert(&self) -> Option<Decomposed<S, V, R>> {
-        if self.scale.approx_eq(&num::zero()) {
+        if self.scale.approx_eq(&zero()) {
             None
         } else {
-            let s = num::one::<S>() / self.scale;
+            let s = one::<S>() / self.scale;
             let r = self.rot.invert();
             let d = r.rotate_vector(&self.disp).mul_s(-s);
             Some(Decomposed {
@@ -144,7 +144,7 @@ pub trait Transform3<S>: Transform<S, Vector3<S>, Point3<S>>+ ToMatrix4<S> {}
 impl<S: BaseFloat + 'static, R: Rotation3<S>> ToMatrix4<S> for Decomposed<S, Vector3<S>, R> {
     fn to_matrix4(&self) -> Matrix4<S> {
         let mut m = self.rot.to_matrix3().mul_s(self.scale.clone()).to_matrix4();
-        m.w = self.disp.extend(num::one());
+        m.w = self.disp.extend(one());
         m
     }
 }
@@ -177,7 +177,7 @@ impl<S: BaseFloat + 'static> Transform<S, Vector3<S>, Point3<S>> for AffineMatri
 
     #[inline]
     fn transform_vector(&self, vec: &Vector3<S>) -> Vector3<S> {
-        self.mat.mul_v(&vec.extend(num::zero())).truncate()
+        self.mat.mul_v(&vec.extend(zero())).truncate()
     }
 
     #[inline]

src/vector.rs

@@ -22,29 +22,27 @@
 //! vector are also provided:
 //!
 //! ```rust
-//! use cgmath::{Vector2, Vector3, Vector4};
+//! use cgmath::{Vector2, Vector3, Vector4, one, zero};
 //!
 //! assert_eq!(Vector2::new(1.0f64, 0.0f64), Vector2::unit_x());
-//! assert_eq!(Vector3::new(0.0f64, 0.0f64, 0.0f64), Vector3::zero());
-//! assert_eq!(Vector4::from_value(1.0f64), Vector4::ident());
+//! assert_eq!(Vector3::new(0.0f64, 0.0f64, 0.0f64), zero());
+//! assert_eq!(Vector4::from_value(1.0f64), one());
 //! ```
 //!
 //! Vectors can be manipulated with typical mathematical operations (addition,
 //! subtraction, element-wise multiplication, element-wise division, negation)
-//! using the built-in operators. The additive and multiplicative inverses
-//! (zero and one) provided by the standard library's `Zero` and `One` are also
-//! available:
+//! using the built-in operators. The additive and multiplicative neutral
+//! elements (zero and one) are also provided by this library
 //!
 //! ```rust
-//! use std::num::{Zero, One};
-//! use cgmath::{Vector2, Vector3, Vector4};
+//! use cgmath::{Vector2, Vector3, Vector4, one, zero};
 //!
 //! let a: Vector2<f64> = Vector2::new(3.0, 4.0);
 //! let b: Vector2<f64> = Vector2::new(-3.0, -4.0);
 //!
-//! assert_eq!(a + b, Zero::zero());
+//! assert_eq!(a + b, zero());
 //! assert_eq!(-(a * b), Vector2::new(9.0f64, 16.0f64));
-//! assert_eq!(a / One::one(), a);
+//! assert_eq!(a / one(), a);
 //!
 //! // As with Rust's `int` and `f32` types, Vectors of different types cannot
 //! // be added and so on with impunity. The following will fail to compile:
@@ -66,13 +64,12 @@
 //! and [cross products](http://en.wikipedia.org/wiki/Cross_product).
 //!
 //! ```rust
-//! use std::num::Zero;
-//! use cgmath::{Vector, Vector2, Vector3, Vector4, dot};
+//! use cgmath::{Vector, Vector2, Vector3, Vector4, dot, zero};
 //!
 //! // All vectors implement the dot product as a method:
 //! let a: Vector2<f64> = Vector2::new(3.0, 6.0);
 //! let b: Vector2<f64> = Vector2::new(-2.0, 1.0);
-//! assert_eq!(a.dot(&b), Zero::zero());
+//! assert_eq!(a.dot(&b), zero());
 //!
 //! // But there is also a top-level function:
 //! assert_eq!(a.dot(&b), dot(a, b));
@@ -101,20 +98,17 @@
 
 use std::fmt;
 use std::mem;
-use std::num::{Zero, zero, One, one};
+use std::num::NumCast;
 
 use angle::{Rad, atan2, acos};
 use approx::ApproxEq;
 use array::{Array1, FixedArray};
-use num::{BaseNum, BaseFloat};
+use num::{BaseNum, BaseFloat, Zero, One, zero, one};
 
 /// A trait that specifies a range of numeric operations for vectors. Not all
 /// of these make sense from a linear algebra point of view, but are included
 /// for pragmatic reasons.
-pub trait Vector<S: BaseNum>: Array1<S>
-                  + Neg<Self>
-                  + Zero
-                  + One {
+pub trait Vector<S: BaseNum>: Array1<S> + Zero + One + Neg<Self> {
     /// Add a scalar to this vector, returning a new vector.
     fn add_s(&self, s: S) -> Self;
     /// Subtract a scalar from this vector, returning a new vector.
@@ -202,14 +196,25 @@ macro_rules! vec(
             }
         }
 
-        impl<$S: BaseNum> $Self<$S> {
-            /// The additive identity of the vector.
+        impl<$S: Zero> Zero for $Self<$S> {
             #[inline]
-            pub fn zero() -> $Self<$S> { $Self::from_value(zero()) }
+            fn zero() -> $Self<S> { $Self { $($field: zero()),+ } }
 
-            /// The multiplicative identity of the vector.
             #[inline]
-            pub fn ident() -> $Self<$S> { $Self::from_value(one()) }
+            fn is_zero(&self) -> bool { $((self.$field.is_zero()) )&&+ }
+        }
+
+        impl<$S: One> One for $Self<$S> {
+            #[inline]
+            fn one() -> $Self<$S> { $Self { $($field: one()),+ } }
+        }
+
+        impl<$S: NumCast + Copy> $Self<$S> {
+            /// Component-wise casting to another type
+            #[inline]
+            pub fn cast<T: NumCast>(&self) -> $Self<T> {
+                $Self { $($field: NumCast::from(self.$field).unwrap()),+ }
+            }
         }
 
         impl<$S> FixedArray<[$S, ..$n]> for $Self<$S> {
@@ -307,11 +312,6 @@ macro_rules! vec(
             #[inline] fn sub(&self, v: &$Self<S>) -> $Self<S> { self.sub_v(v) }
         }
 
-        impl<S: BaseNum> Zero for $Self<S> {
-            #[inline] fn zero() -> $Self<S> { $Self::from_value(zero()) }
-            #[inline] fn is_zero(&self) -> bool { *self == zero() }
-        }
-
         impl<S: BaseNum> Neg<$Self<S>> for $Self<S> {
             #[inline] fn neg(&self) -> $Self<S> { $Self::new($(-self.$field),+) }
         }
@@ -328,10 +328,6 @@ macro_rules! vec(
             #[inline] fn rem(&self, v: &$Self<S>) -> $Self<S> { self.rem_v(v) }
         }
 
-        impl<S: BaseNum> One for $Self<S> {
-            #[inline] fn one() -> $Self<S> { $Self::from_value(one()) }
-        }
-
         impl<S: BaseFloat> ApproxEq<S> for $Self<S> {
             #[inline]
             fn approx_eq_eps(&self, other: &$Self<S>, epsilon: &S) -> bool {

tests/vector.rs

@@ -14,7 +14,10 @@
 // limitations under the License.
 
 #![feature(globs)]
+#![feature(phase)]
 
+#[phase(plugin)]
+extern crate cgmath;
 extern crate cgmath;
 
 use cgmath::*;
@@ -166,3 +169,10 @@ fn test_map() {
     assert_eq!(Vector3::new(7.12f64, 3.8f64, -6.98f64).map(|x| x.floor()), Vector3::new(7.0f64, 3.0f64, -7.0f64));
     assert_eq!(Vector3::new(7.12f64, 3.8f64, -6.98f64).map(|x| x.max(0.0f64)), Vector3::new(7.12f64, 3.8f64, 0.0f64));
 }
+
+#[test]
+fn test_cast() {
+    assert_approx_eq!(Vector2::new(0.9f64, 1.5).cast(), Vector2::new(0.9f32, 1.5));
+    assert_approx_eq!(Vector3::new(1.0f64, 2.4, -3.13).cast(), Vector3::new(1.0f32, 2.4, -3.13));
+    assert_approx_eq!(Vector4::new(13.5f64, -4.6, -8.3, 2.41).cast(), Vector4::new(13.5f32, -4.6, -8.3, 2.41));
+}