diff --git a/rtiow/src/perlin.rs b/rtiow/src/perlin.rs
index 2c3a393..7e99cb6 100644
--- a/rtiow/src/perlin.rs
+++ b/rtiow/src/perlin.rs
@@ -31,21 +31,11 @@ fn perlin_generate() -> Vec<Vec3> {
         }).collect()
 }
 
-fn permute(p: &mut Vec<usize>, n: usize) {
+fn perlin_generate_perm() -> Vec<usize> {
     //let mut rng: XorShiftRng = SeedableRng::from_seed(SEED);
     let mut rng = rand::thread_rng();
-    let mut random = || rng.gen_range::<f32>(0., 1.);
-    for i in (0..n).rev() {
-        let target = (random() * (i + 1) as f32) as usize;
-        let tmp = p[i];
-        p[i] = p[target];
-        p[target] = tmp;
-    }
-}
-
-fn perlin_generate_perm() -> Vec<usize> {
     let mut p: Vec<usize> = (0..256).map(|i| i).collect();
-    permute(p.as_mut(), 256);
+    rng.shuffle(&mut p);
     p
 }
 
diff --git a/rtiow/src/renderer.rs b/rtiow/src/renderer.rs
index ed3ef68..d20b689 100644
--- a/rtiow/src/renderer.rs
+++ b/rtiow/src/renderer.rs
@@ -28,6 +28,7 @@ pub enum Model {
     Test,
     CornellBox,
     CornellSmoke,
+    PerlinDebug,
 }
 
 impl Model {
@@ -40,6 +41,7 @@ impl Model {
             Model::Test => scenes::test::new(&opt),
             Model::CornellBox => scenes::cornell_box::new(&opt),
             Model::CornellSmoke => scenes::cornell_smoke::new(&opt),
+            Model::PerlinDebug => scenes::perlin_debug::new(&opt),
         }
     }
 }
@@ -64,6 +66,7 @@ impl str::FromStr for Model {
             "test" => Ok(Model::Test),
             "cornell_box" => Ok(Model::CornellBox),
             "cornell_smoke" => Ok(Model::CornellSmoke),
+            "perlin_debug" => Ok(Model::PerlinDebug),
             _ => Err(ModelParseError(s.to_owned())),
         }
     }
@@ -82,8 +85,8 @@ pub struct Opt {
     #[structopt(short = "s", long = "subsample", default_value = "8")]
     pub subsamples: usize,
     /// Select scene to render, one of: "bench", "book", "tutorial", "bvh", "test", "cornell_box",
-    /// "cornell_smoke"
-    #[structopt(long = "model", default_value = "cornell_smoke")]
+    /// "cornell_smoke", "perlin_debug"
+    #[structopt(long = "model", default_value = "perlin_debug")]
     pub model: Model,
     /// Path to store pprof profile data, i.e. /tmp/cpuprofile.pprof
     #[structopt(long = "pprof", parse(from_os_str))]
diff --git a/rtiow/src/scenes/mod.rs b/rtiow/src/scenes/mod.rs
index f6f2b2c..ae0cd14 100644
--- a/rtiow/src/scenes/mod.rs
+++ b/rtiow/src/scenes/mod.rs
@@ -3,5 +3,6 @@ pub mod book;
 pub mod bvh;
 pub mod cornell_box;
 pub mod cornell_smoke;
+pub mod perlin_debug;
 pub mod test;
 pub mod tutorial;
diff --git a/rtiow/src/scenes/perlin_debug.rs b/rtiow/src/scenes/perlin_debug.rs
new file mode 100644
index 0000000..4edd561
--- /dev/null
+++ b/rtiow/src/scenes/perlin_debug.rs
@@ -0,0 +1,60 @@
+use std::sync::Arc;
+
+use camera::Camera;
+use hitable::Hit;
+use hitable_list::HitableList;
+use kdtree::KDTree;
+use material::Lambertian;
+use renderer::Opt;
+use renderer::Scene;
+use sphere::Sphere;
+use texture::NoiseTexture;
+use texture::Texture;
+use vec3::Vec3;
+
+pub fn new(opt: &Opt) -> Scene {
+    let lookfrom = Vec3::new(13., 2., 3.);
+    let lookat = Vec3::new(0., 0., 0.);
+    let dist_to_focus = 10.0;
+    let aperture = 0.0;
+    let time_min = 0.;
+    let time_max = 1.;
+    let camera = Camera::new(
+        lookfrom,
+        lookat,
+        Vec3::new(0., 1., 0.),
+        20.,
+        opt.width as f32 / opt.height as f32,
+        aperture,
+        dist_to_focus,
+        time_min,
+        time_max,
+    );
+    let pertext: Arc<Texture> = Arc::new(NoiseTexture::with_scale(10.));
+
+    let objects: Vec<Box<Hit>> = vec![
+        Box::new(Sphere::new(
+            Vec3::new(0., -1000., 0.),
+            1000.,
+            Lambertian::new(Arc::clone(&pertext)),
+        )),
+        Box::new(Sphere::new(
+            Vec3::new(0., 2., 0.),
+            2.0,
+            Lambertian::new(Arc::clone(&pertext)),
+        )),
+    ];
+    let world: Box<Hit> = if opt.use_accel {
+        Box::new(KDTree::new(objects, time_min, time_max))
+    } else {
+        Box::new(HitableList::new(objects))
+    };
+    Scene {
+        camera,
+        world,
+        subsamples: opt.subsamples,
+        width: opt.width,
+        height: opt.height,
+        global_illumination: true,
+    }
+}
diff --git a/rtiow/src/texture.rs b/rtiow/src/texture.rs
index 255f768..ad5cfcb 100644
--- a/rtiow/src/texture.rs
+++ b/rtiow/src/texture.rs
@@ -1,12 +1,21 @@
+use std::sync::Arc;
+
 use image::RgbImage;
 
 use perlin::turb;
+use perlin::GENERATOR;
 use vec3::Vec3;
 
 pub trait Texture: Send + Sync {
     fn value(&self, u: f32, v: f32, p: Vec3) -> Vec3;
 }
 
+impl Texture for Arc<Texture> {
+    fn value(&self, u: f32, v: f32, p: Vec3) -> Vec3 {
+        (**self).value(u, v, p)
+    }
+}
+
 #[derive(Debug, PartialEq)]
 pub struct ConstantTexture {
     color: Vec3,
@@ -75,9 +84,11 @@ impl NoiseTexture {
 
 impl Texture for NoiseTexture {
     fn value(&self, _u: f32, _v: f32, p: Vec3) -> Vec3 {
-        Vec3::new(1., 1., 1.) * turb(self.scale * p, 7)
+        let _ = GENERATOR;
+        let _ = turb;
+        //Vec3::new(1., 1., 1.) * turb(self.scale * p, 7)
         //Vec3::new(1., 1., 1.) * 0.5 * (1. + turb(self.scale * p, 7))
-        //Vec3::new(1., 1., 1.) * 0.5 * (1. + (self.scale * p.x + 5. * turb(p, 7)).sin())
+        Vec3::new(1., 1., 1.) * 0.5 * (1. + (self.scale * p.z + 10. * turb(p, 7)).sin())
         //Vec3::new(1., 1., 1.) * 0.5 * (1. + GENERATOR.noise(self.scale * p))
     }
 }