From 3316a77192183a4cf25904ab2381ab126bfe617a Mon Sep 17 00:00:00 2001
From: Brendan Zabarauskas <bjzaba@yahoo.com.au>
Date: Wed, 7 Nov 2012 12:36:35 +1000
Subject: [PATCH] Add mat4_from_rotation function

---
 src/funs/transform.rs | 20 ++++++++++++++++++++
 src/lmath.rc          |  1 +
 2 files changed, 21 insertions(+)
 create mode 100644 src/funs/transform.rs

diff --git a/src/funs/transform.rs b/src/funs/transform.rs
new file mode 100644
index 0000000..2ce818e
--- /dev/null
+++ b/src/funs/transform.rs
@@ -0,0 +1,20 @@
+use num::Num;
+use ncast::*;
+use funs::exp::*;
+use funs::trig::*;
+use matrix::Mat4;
+
+fn mat4_from_rotation<T:Copy Num NumCast Exp Trig>(axis: Vec3<T>, angle: T) -> Mat4<T> {
+    let angle_rad = radians(&angle);
+    let c = cos(&angle_rad);
+    let s = sin(&angle_rad);
+    
+    let _0: T = cast(0);
+    let _1: T = cast(1);
+    let t = _1 - c;
+    
+    Mat4::new(t * axis.x * axis.x + c,          t * axis.x * axis.y + s * axis.z, t * axis.x * axis.z - s * axis.y, _0,
+              t * axis.x * axis.y - s * axis.z, t * axis.y * axis.y + c,          t * axis.y * axis.z + s * axis.x, _0,
+              t * axis.x * axis.z - s - axis.y, t * axis.y * axis.z - s * axis.x, t * axis.z * axis.z + c,          _0,
+              _0, _0, _0, _1)
+}
\ No newline at end of file
diff --git a/src/lmath.rc b/src/lmath.rc
index 89f5f74..8e54154 100644
--- a/src/lmath.rc
+++ b/src/lmath.rc
@@ -35,6 +35,7 @@ pub mod funs {
   pub mod common;
   pub mod exp;
   pub mod relv;
+  pub mod transform;
   pub mod trig;
   
   #[test]