Add to_homogeneous conversion method

src/vec.rs

@@ -199,7 +199,7 @@ pub trait NumericVector2<T>: NumericVector<T> {
 /**
  * A 3-dimensional vector with numeric components
  */
-pub trait NumericVector3<T>: NumericVector<T> {
+pub trait NumericVector3<T,HV>: NumericVector<T> {
     // static pure fn unit_x() -> self;
     // static pure fn unit_y() -> self;
     // static pure fn unit_z() -> self;
@@ -210,6 +210,11 @@ pub trait NumericVector3<T>: NumericVector<T> {
      * The cross product of the vector and `other`
      */
     pure fn cross(&self, other: &self) -> self;
+    
+    /**
+     * Convert the vector to its homogeneous form
+     */
+    pure fn to_homogeneous(&self) -> HV;
 }
 
 /**

src/vec3.rs

@@ -10,6 +10,8 @@ use numeric::types::float::Float;
 use numeric::types::number::Number;
 use numeric::types::number::Number::{one, zero};
 
+use vec::Vec4;
+
 /**
  * A 3-dimensional vector
  *
@@ -201,13 +203,17 @@ pub impl<T:Copy Number> Vec3<T>: MutableNumericVector<&self/T> {
     }
 }
 
-pub impl<T:Copy Number> Vec3<T>: NumericVector3<T> {
+pub impl<T:Copy Number> Vec3<T>: NumericVector3<T,Vec4<T>> {
     #[inline(always)]
     pure fn cross(&self, other: &Vec3<T>) -> Vec3<T> {
         Vec3::new((self[1] * other[2]) - (self[2] * other[1]),
                   (self[2] * other[0]) - (self[0] * other[2]),
                   (self[0] * other[1]) - (self[1] * other[0]))
     }
+    
+    pure fn to_homogeneous(&self) -> Vec4<T> {
+        Vec4::new(self.x, self.y, self.z, zero())
+    }
 }
 
 pub impl<T:Copy Number> Vec3<T>: MutableNumericVector3<&self/T> {