From 7635d0127660ebd6b1aebe794d2a10c68d8da2b4 Mon Sep 17 00:00:00 2001
From: Brendan Zabarauskas <bjzaba@yahoo.com.au>
Date: Tue, 3 Sep 2013 22:12:54 +1000
Subject: [PATCH] Add normalize_self, normalize_self_to and lerp_self methods

---
 src/cgmath/vector.rs | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/src/cgmath/vector.rs b/src/cgmath/vector.rs
index 2dbd804..06ff90d 100644
--- a/src/cgmath/vector.rs
+++ b/src/cgmath/vector.rs
@@ -199,11 +199,32 @@ pub trait EuclideanVector
     }
 
     /// Returns the result of linarly interpolating the length of the vector
-    /// to the length of `other` by the specified amount.
+    /// towards the length of `other` by the specified amount.
     #[inline]
     fn lerp(&self, other: &Self, amount: S) -> Self {
         self.add_v(&other.sub_v(self).mul_s(amount))
     }
+
+    /// Normalises the vector to a length of `1`.
+    #[inline]
+    fn normalize_self(&mut self) {
+        let rlen = self.length().recip();
+        self.mul_self_s(rlen);
+    }
+
+    /// Normalizes the vector to `length`.
+    #[inline]
+    fn normalize_self_to(&mut self, length: S) {
+        let n = length / self.length();
+        self.mul_self_s(n);
+    }
+
+    /// Linearly interpolates the length of the vector towards the length of
+    /// `other` by the specified amount.
+    fn lerp_self(&mut self, other: &Self, amount: S) {
+        let v = other.sub_v(self).mul_s(amount);
+        self.add_self_v(&v);
+    }
 }
 
 impl<S: Clone + Float> EuclideanVector<S, [S, ..2]> for Vec2<S> {