From a9273389ea064ba10782dfd55c7bb9d93828ffbe Mon Sep 17 00:00:00 2001
From: Brendan Zabarauskas <bjzaba@yahoo.com.au>
Date: Wed, 14 Nov 2012 17:55:55 +1000
Subject: [PATCH] Improve length tests and add distance tests

---
 src/test/test_vector.rs | 87 +++++++++++++++++++++++++++++------------
 src/vector.rs           |  7 ----
 2 files changed, 63 insertions(+), 31 deletions(-)

diff --git a/src/test/test_vector.rs b/src/test/test_vector.rs
index 7ae1f88..98959c5 100644
--- a/src/test/test_vector.rs
+++ b/src/test/test_vector.rs
@@ -38,19 +38,32 @@ fn test_Vec2() {
     // fuzzy_eq
     // eq
     
-    assert a.length2().fuzzy_eq(&5f);
-    assert a.length().fuzzy_eq(&2.236068f);
-    
-    let c = Vec2::new(-2.0f, -1.0f);
-    let d = Vec2::new( 1.0f,  0.0f);
-    let f3 = 0.75f;
-    
-    assert c.lerp(&d, f3) == Vec2::new(0.250f, -0.250f);
     // assert c.abs()       == Vec2::new( 2.0f,  1.0f);
     // assert c.min(&d)      == Vec2::new(-2.0f, -1.0f);
     // assert c.max(&d)      == Vec2::new( 1.0f,  0.0f);
 }
 
+#[test]
+fn test_Vec2_geometric() {
+    let a = Vec2::new(5f, 12f); // (5, 12, 13) Pythagorean triple
+    let b0 = Vec2::new(3f, 4f); // (3, 4, 5) Pythagorean triple
+    let b = a.add_v(&b0);
+    
+    assert a.length() == 13f;
+    assert a.length2() == 13f * 13f;
+    
+    assert b0.length() == 5f;
+    assert b0.length2() == 5f * 5f;
+    
+    assert a.distance(&b) == 5f;
+    assert a.distance2(&b) == 5f * 5f;
+    
+    let c = Vec2::new(-2.0f, -1.0f);
+    let d = Vec2::new( 1.0f,  0.0f);
+    
+    assert c.lerp(&d, 0.75f) == Vec2::new(0.250f, -0.250f);
+}
+
 #[test]
 fn test_Vec3() {
     // assert Vec3::dim == 3;
@@ -91,19 +104,32 @@ fn test_Vec3() {
     // fuzzy_eq
     // eq
     
-    assert a.length2().fuzzy_eq(&14f);
-    assert a.length().fuzzy_eq(&3.74165738677f);
-    
-    let c = Vec3::new(-2.0f, -1.0f, 1.0f);
-    let d = Vec3::new( 1.0f,  0.0f, 0.5f);
-    let f3 = 0.75f;
-    
-    assert c.lerp(&d, f3) == Vec3::new(0.250f, -0.250f, 0.625f);
     // assert c.abs()        == Vec3::new( 2.0f,  1.0f, 1.0f);
     // assert c.min(&d)      == Vec3::new(-2.0f, -1.0f, 0.5f);
     // assert c.max(&d)      == Vec3::new( 1.0f,  0.0f, 1.0f);
 }
 
+#[test]
+fn test_Vec3_geometric() {
+    let a = Vec3::new(2f, 3f, 6f); // (2, 3, 6, 7) Pythagorean quadruple
+    let b0 = Vec3::new(1f, 4f, 8f); // (1, 4, 8, 9) Pythagorean quadruple
+    let b = a.add_v(&b0);
+    
+    assert a.length() == 7f;
+    assert a.length2() == 7f * 7f;
+    
+    assert b0.length() == 9f;
+    assert b0.length2() == 9f * 9f;
+    
+    assert a.distance(&b) == 9f;
+    assert a.distance2(&b) == 9f * 9f;
+    
+    let c = Vec3::new(-2.0f, -1.0f, 1.0f);
+    let d = Vec3::new( 1.0f,  0.0f, 0.5f);
+    
+    assert c.lerp(&d, 0.75f) == Vec3::new(0.250f, -0.250f, 0.625f);
+}
+
 #[test]
 fn test_Vec4() {
     // assert Vec4::dim == 4;
@@ -147,15 +173,28 @@ fn test_Vec4() {
     // fuzzy_eq
     // eq
     
-    assert a.length2().fuzzy_eq(&30f);
-    assert a.length().fuzzy_eq(&5.477226f);
-    
-    let c = Vec4::new(-2.0f, -1.0f, 1.0f, 2.0f);
-    let d = Vec4::new( 1.0f,  0.0f, 0.5f, 1.0f);
-    let f3 = 0.75f;
-    
-    assert c.lerp(&d, f3) == Vec4::new(0.250f, -0.250f, 0.625f, 1.250f);
     // assert c.abs()        == Vec4::new( 2.0f,  1.0f, 1.0f, 2.0f);
     // assert c.min(&d)      == Vec4::new(-2.0f, -1.0f, 0.5f, 1.0f);
     // assert c.max(&d)      == Vec4::new( 1.0f,  0.0f, 1.0f, 2.0f);
+}
+
+#[test]
+fn test_Vec4_geometric() {
+    let a = Vec4::new(1f, 2f, 4f, 10f); // (1, 2, 4, 10, 11) Pythagorean quintuple
+    let b0 = Vec4::new(1f, 2f, 8f, 10f); // (1, 2, 8, 10, 13) Pythagorean quintuple
+    let b = a.add_v(&b0);
+    
+    assert a.length() == 11f;
+    assert a.length2() == 11f * 11f;
+    
+    assert b0.length() == 13f;
+    assert b0.length2() == 13f * 13f;
+    
+    assert a.distance(&b) == 13f;
+    assert a.distance2(&b) == 13f * 13f;
+
+    let c = Vec4::new(-2.0f, -1.0f, 1.0f, 2.0f);
+    let d = Vec4::new( 1.0f,  0.0f, 0.5f, 1.0f);
+    
+    assert c.lerp(&d, 0.75f) == Vec4::new(0.250f, -0.250f, 0.625f, 1.250f);
 }
\ No newline at end of file
diff --git a/src/vector.rs b/src/vector.rs
index 2219a47..cf6e9da 100644
--- a/src/vector.rs
+++ b/src/vector.rs
@@ -185,13 +185,11 @@ pub impl<T:Copy Num NumCast Exp> Vec2<T>: GeometricVector<T> {
         self.length2().sqrt()
     }
     
-    // TODO: tests
     #[inline(always)]
     pure fn distance2(other: &Vec2<T>) -> T {
         other.sub_v(&self).length2()
     }
     
-    // TODO: tests
     #[inline(always)]
     pure fn distance(other: &Vec2<T>) -> T {
         other.distance2(&self).sqrt()
@@ -375,13 +373,11 @@ pub impl<T:Copy Num NumCast Exp> Vec3<T>: GeometricVector<T> {
         self.length2().sqrt()
     }
     
-    // TODO: tests
     #[inline(always)]
     pure fn distance2(other: &Vec3<T>) -> T {
         other.sub_v(&self).length2()
     }
     
-    // TODO: tests
     #[inline(always)]
     pure fn distance(other: &Vec3<T>) -> T {
         other.distance2(&self).sqrt()
@@ -442,7 +438,6 @@ pub impl<T:Copy FuzzyEq> Vec3<T>: FuzzyEq {
 pub struct Vec4<T> { x: T, y: T, z: T, w: T }
 
 pub mod Vec4 {
-    
     #[inline(always)]
     pub pure fn new<T>(x: T, y: T, z: T, w: T) -> Vec4<T> {
         Vec4 { x: move x, y: move y, z: move z, w: move w }
@@ -570,13 +565,11 @@ pub impl<T:Copy Num NumCast Exp> Vec4<T>: GeometricVector<T> {
         self.length2().sqrt()
     }
     
-    // TODO: tests
     #[inline(always)]
     pure fn distance2(other: &Vec4<T>) -> T {
         other.sub_v(&self).length2()
     }
     
-    // TODO: tests
     #[inline(always)]
     pure fn distance(other: &Vec4<T>) -> T {
         other.distance2(&self).sqrt()