Add impl Interpolate for some cgmath types.

Cargo.toml

@@ -18,3 +18,4 @@ is-it-maintained-open-issues = { repository = "phaazon/spline" }
 maintenance = { status = "actively-developed" }
 
 [dependencies]
+cgmath = "0.16"

src/lib.rs

@@ -64,6 +64,9 @@
 //!
 //! Feel free to have a look at the rest of the documentation for advanced usage.
 
+extern crate cgmath;
+
+use cgmath::{InnerSpace, Quaternion, Vector2, Vector3, Vector4};
 use std::cmp::Ordering;
 use std::f32::consts;
 use std::ops::{Add, Div, Mul, Sub};
@@ -285,6 +288,42 @@ impl Interpolate for f32 {
   }
 }
 
+impl Interpolate for Vector2<f32> {
+  fn lerp(a: Self, b: Self, t: f32) -> Self {
+    a.lerp(b, t)
+  }
+
+  fn cubic_hermite(x: (Self, f32), a: (Self, f32), b: (Self, f32), y: (Self, f32), t: f32) -> Self {
+    cubic_hermite(x, a, b, y, t)
+  }
+}
+
+impl Interpolate for Vector3<f32> {
+  fn lerp(a: Self, b: Self, t: f32) -> Self {
+    a.lerp(b, t)
+  }
+
+  fn cubic_hermite(x: (Self, f32), a: (Self, f32), b: (Self, f32), y: (Self, f32), t: f32) -> Self {
+    cubic_hermite(x, a, b, y, t)
+  }
+}
+
+impl Interpolate for Vector4<f32> {
+  fn lerp(a: Self, b: Self, t: f32) -> Self {
+    a.lerp(b, t)
+  }
+
+  fn cubic_hermite(x: (Self, f32), a: (Self, f32), b: (Self, f32), y: (Self, f32), t: f32) -> Self {
+    cubic_hermite(x, a, b, y, t)
+  }
+}
+
+impl Interpolate for Quaternion<f32> {
+  fn lerp(a: Self, b: Self, t: f32) -> Self {
+    a.nlerp(b, t)
+  }
+}
+
 // Default implementation of Interpolate::cubic_hermit.
 pub(crate) fn cubic_hermite<T>(x: (T, f32), a: (T, f32), b: (T, f32), y: (T, f32), t: f32) -> T
     where T: Copy + Add<Output = T> + Sub<Output = T> + Mul<f32, Output = T> + Div<f32, Output = T> {