From 16e06c3855ccc871e1b2394c6e4a7fd4f9ea51c5 Mon Sep 17 00:00:00 2001
From: Brendan Zabarauskas <bjzaba@yahoo.com.au>
Date: Mon, 24 Dec 2012 13:46:25 +1000
Subject: [PATCH] Add is_zero method to Vector trait

---
 src/test/test_vec.rs | 9 +++++++++
 src/vec.rs           | 7 +++++++
 src/vec2.rs          | 6 ++++++
 src/vec3.rs          | 7 +++++++
 src/vec4.rs          | 8 ++++++++
 5 files changed, 37 insertions(+)

diff --git a/src/test/test_vec.rs b/src/test/test_vec.rs
index f4993f3..6c440b0 100644
--- a/src/test/test_vec.rs
+++ b/src/test/test_vec.rs
@@ -43,6 +43,9 @@ fn test_vec2() {
     assert -a      == Vec2::new(-1f, -2f);
     assert a.neg() == Vec2::new(-1f, -2f);
     
+    assert Vec2::new(0f, 0f).is_zero();
+    assert !Vec2::new(1f, 1f).is_zero();
+    
     assert a.mul_t(f1) == Vec2::new( 1.5f, 3.0f);
     assert a.div_t(f2) == Vec2::new( 2.0f, 4.0f);
     
@@ -183,6 +186,9 @@ fn test_vec3() {
     assert -a      == Vec3::new(-1f, -2f, -3f);
     assert a.neg() == Vec3::new(-1f, -2f, -3f);
     
+    assert Vec3::new(0f, 0f, 0f).is_zero();
+    assert !Vec3::new(1f, 1f, 1f).is_zero();
+    
     assert a.mul_t(f1) == Vec3::new( 1.5f, 3.0f, 4.5f);
     assert a.div_t(f2) == Vec3::new( 2.0f, 4.0f, 6.0f);
     
@@ -325,6 +331,9 @@ fn test_vec4() {
     assert -a      == Vec4::new(-1f, -2f, -3f, -4f);
     assert a.neg() == Vec4::new(-1f, -2f, -3f, -4f);
     
+    assert Vec4::new(0f, 0f, 0f, 0f).is_zero();
+    assert !Vec4::new(1f, 1f, 1f, 1f).is_zero();
+    
     assert a.mul_t(f1) == Vec4::new( 1.5f, 3.0f, 4.5f, 6.0f);
     assert a.div_t(f2) == Vec4::new( 2.0f, 4.0f, 6.0f, 8.0f);
     
diff --git a/src/vec.rs b/src/vec.rs
index 2a7366b..e5cce18 100644
--- a/src/vec.rs
+++ b/src/vec.rs
@@ -91,6 +91,13 @@ pub trait NumericVector<T>: Vector<T> Neg<self> {
      */
     static pure fn zero() -> self;
     
+    /**
+     * # Return value
+     *
+     * True if the vector is equal to zero
+     */
+    pure fn is_zero(&self) -> bool;
+    
     /**
      * # Return value
      *
diff --git a/src/vec2.rs b/src/vec2.rs
index 3660e87..d712f8a 100644
--- a/src/vec2.rs
+++ b/src/vec2.rs
@@ -85,6 +85,12 @@ pub impl<T:Copy Number> Vec2<T>: NumericVector<T> {
                   Number::zero())
     }
     
+    #[inline(always)]
+    pure fn is_zero(&self) -> bool {
+        self[0] == Number::zero() &&
+        self[1] == Number::zero()
+    }
+    
     #[inline(always)]
     pure fn mul_t(&self, value: T) -> Vec2<T> {
         Vec2::new(self[0] * value,
diff --git a/src/vec3.rs b/src/vec3.rs
index 3ab107d..2dc98e8 100644
--- a/src/vec3.rs
+++ b/src/vec3.rs
@@ -89,6 +89,13 @@ pub impl<T:Copy Number> Vec3<T>: NumericVector<T> {
                   Number::zero())
     }
     
+    #[inline(always)]
+    pure fn is_zero(&self) -> bool {
+        self[0] == Number::zero() &&
+        self[1] == Number::zero() &&
+        self[2] == Number::zero()
+    }
+    
     #[inline(always)]
     pure fn mul_t(&self, value: T) -> Vec3<T> {
         Vec3::new(self[0] * value,
diff --git a/src/vec4.rs b/src/vec4.rs
index 2a55126..6586d7e 100644
--- a/src/vec4.rs
+++ b/src/vec4.rs
@@ -93,6 +93,14 @@ pub impl<T:Copy Number> Vec4<T>: NumericVector<T> {
                   Number::zero())
     }
     
+    #[inline(always)]
+    pure fn is_zero(&self) -> bool {
+        self[0] == Number::zero() &&
+        self[1] == Number::zero() &&
+        self[2] == Number::zero() &&
+        self[3] == Number::zero()
+    }
+    
     #[inline(always)]
     pure fn mul_t(&self, value: T) -> Vec4<T> {
         Vec4::new(self[0] * value,