4 files changed, 17 insertions, 7 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 5897394..384881e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -5,6 +5,7 @@ dependencies = [
  "getopts 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "glium 0.14.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "image 0.10.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "time 0.1.35 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -564,6 +565,16 @@ dependencies = [
 ]
 
 [[package]]
+name = "time"
+version = "0.1.35"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.12 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "user32-sys"
 version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/Cargo.toml b/Cargo.toml
index 5aa372f..1652bad 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,4 +11,5 @@ authors = ["bnewbold <bnewbold@robocracy.org>"]
 glium = "0.*"
 image = "0.*"
 getopts = "^0.2"
+time = "0.1"
 
diff --git a/src/bin/exuberantbovines.rs b/src/bin/exuberantbovines.rs
index 799fff5..e07f28c 100644
--- a/src/bin/exuberantbovines.rs
+++ b/src/bin/exuberantbovines.rs
@@ -12,7 +12,6 @@ use glium::Surface;
 mod cow_model;
 
 struct ExuberantBovines {
-    t: f64,
     display: glium::Display,
     program: glium::Program,
     model_vertices: Vec<glium::VertexBuffer<cow_model::Vertex>>,
@@ -92,7 +91,6 @@ impl ExuberantBovines {
         return ExuberantBovines {
             display: display,
             program: program,
-            t: 0.0,
             model_vertices: vec![face_vertices,
                                  hide_vertices,
                                  hoofs_vertices,
@@ -105,12 +103,11 @@ impl ExuberantBovines {
 
 impl ExuberantHack for ExuberantBovines {
 
-    fn draw_frame(&mut self) -> Result<(), String> {
+    fn draw_frame(&mut self, t: f64) -> Result<(), String> {
 
         let indices = glium::index::NoIndices(glium::index::PrimitiveType::TrianglesList);
 
-        self.t += 0.03;
-        let z: f32 = 0.5 * self.t.sin() as f32;
+        let z: f32 = 0.5 * t.sin() as f32;
 
         // Drawing Pipeline
         let mut target = self.display.draw();
diff --git a/src/lib.rs b/src/lib.rs
index c73fc0c..f24c658 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -4,6 +4,7 @@ extern crate glium;
 
 extern crate image;
 extern crate getopts;
+extern crate time;
 
 use std::env;
 use std::process::exit;
@@ -14,7 +15,7 @@ use glium::{DisplayBuild, Display};
 pub mod util;
 
 pub trait ExuberantHack {
-    fn draw_frame(&mut self) -> Result<(), String>;
+    fn draw_frame(&mut self, t: f64) -> Result<(), String>;
     fn get_display(&self) -> &Display;
 }
 
@@ -30,7 +31,7 @@ pub fn print_usage(opts: &Options) {
 pub fn run(hack: &mut ExuberantHack, conf: &Matches) {
 
     loop {
-        hack.draw_frame().ok();
+        hack.draw_frame(time::precise_time_s()).ok();
         for ev in hack.get_display().poll_events() {
             match ev {
                 glium::glutin::Event::Closed => return,