Add static methods to build canonical axis.

For exemple use: Vec3::x() to create the vector Vec3::new(1.0, 0.0, 0.0).
The same aplies for y, z, w, etc.

README.md

@@ -10,8 +10,7 @@ usable for graphics too.
 
 ## Compilation
 You will need the last rust compiler from the master branch.
-I pull the compiler and fix my code almost every days. If you encounter
+If you encounter problems, make sure you have the last version before creating an issue.
-problems, make sure you have the last version.
 
     git clone git://github.com/sebcrozet/nalgebra.git
     cd nalgebra

src/vec.rs

@@ -40,6 +40,7 @@ pub struct Vec1<N>
 }
 
 new_impl!(Vec1, x)
+vec_axis_impl!(Vec1, x)
 vec_cast_impl!(Vec1, x)
 indexable_impl!(Vec1, 1)
 new_repeat_impl!(Vec1, val, x)
@@ -77,6 +78,7 @@ pub struct Vec2<N>
 }
 
 new_impl!(Vec2, x, y)
+vec_axis_impl!(Vec2, x, y)
 vec_cast_impl!(Vec2, x, y)
 indexable_impl!(Vec2, 2)
 new_repeat_impl!(Vec2, val, x, y)
@@ -118,6 +120,7 @@ pub struct Vec3<N>
 
 
 new_impl!(Vec3, x, y, z)
+vec_axis_impl!(Vec3, x, y, z)
 vec_cast_impl!(Vec3, x, y, z)
 indexable_impl!(Vec3, 3)
 new_repeat_impl!(Vec3, val, x, y, z)
@@ -159,6 +162,7 @@ pub struct Vec4<N>
 }
 
 new_impl!(Vec4, x, y, z, w)
+vec_axis_impl!(Vec4, x, y, z, w)
 vec_cast_impl!(Vec4, x, y, z, w)
 indexable_impl!(Vec4, 4)
 new_repeat_impl!(Vec4, val, x, y, z, w)
@@ -202,6 +206,7 @@ pub struct Vec5<N>
 }
 
 new_impl!(Vec5, x, y, z, w, a)
+vec_axis_impl!(Vec5, x, y, z, w, a)
 vec_cast_impl!(Vec5, x, y, z, w, a)
 indexable_impl!(Vec5, 5)
 new_repeat_impl!(Vec5, val, x, y, z, w, a)
@@ -247,6 +252,7 @@ pub struct Vec6<N>
 }
 
 new_impl!(Vec6, x, y, z, w, a, b)
+vec_axis_impl!(Vec6, x, y, z, w, a, b)
 vec_cast_impl!(Vec6, x, y, z, w, a, b)
 indexable_impl!(Vec6, 6)
 new_repeat_impl!(Vec6, val, x, y, z, w, a, b)

src/vec_macros.rs

@@ -16,6 +16,38 @@ macro_rules! new_impl(
     }
   )
 )
+
+macro_rules! vec_axis_impl(
+  ($t: ident, $comp0: ident $(,$compN: ident)*) => (
+    impl<N: Zero + One> $t<N>
+    {
+      /// Create a unit vector with its `$comp0` component equal to 1.0.
+      #[inline]
+      pub fn $comp0() -> $t<N>
+      {
+        let mut res: $t<N> = Zero::zero();
+
+        res.$comp0 = One::one();
+
+        res
+      }
+
+      $(
+        /// Create a unit vector with its `$compN` component equal to 1.0.
+        #[inline]
+        pub fn $compN() -> $t<N>
+        {
+          let mut res: $t<N> = Zero::zero();
+
+          res.$compN = One::one();
+
+          res
+        }
+      )*
+    }
+  )
+)
+
 macro_rules! vec_cast_impl(
   ($t: ident, $comp0: ident $(,$compN: ident)*) => (
     impl<Nin: NumCast + Clone, Nout: NumCast> VecCast<$t<Nout>> for $t<Nin>