From 34817ebc3f9f06113e5e6c56f473c34834198860 Mon Sep 17 00:00:00 2001
From: Fay Carsons <faycarsons23@gmail.com>
Date: Sat, 13 Jan 2024 13:17:22 -0500
Subject: [PATCH 1/5] added flowfield example, dune fmt

---
 examples/dune         |   5 ++
 examples/flowfield.ml |  96 ++++++++++++++++++++++++++++++++
 examples/noise.ml     | 124 ++++++++++++++++++++++++++++++++++++++++++
 examples/noise.mli    |  12 ++++
 lib/shape.ml          |   4 ++
 5 files changed, 241 insertions(+)
 create mode 100644 examples/flowfield.ml
 create mode 100644 examples/noise.ml
 create mode 100644 examples/noise.mli

diff --git a/examples/dune b/examples/dune
index 1c42610..0887f20 100644
--- a/examples/dune
+++ b/examples/dune
@@ -102,3 +102,8 @@
  (name donut_with_scale)
  (modules donut_with_scale)
  (libraries joy))
+
+(executable 
+ (name flowfield)
+ (modules flowfield noise)
+ (libraries joy base))
diff --git a/examples/flowfield.ml b/examples/flowfield.ml
new file mode 100644
index 0000000..4c726e3
--- /dev/null
+++ b/examples/flowfield.ml
@@ -0,0 +1,96 @@
+open Noise
+open Joy
+
+let size = 800
+let tau = 2. *. Float.pi
+let num_steps = 8
+let grid_divisor = 64
+let octaves = 6
+let noise_scale = 4.
+let _ = Stdlib.Random.self_init
+let seed = Stdlib.Random.float 1000.
+
+let palette =
+  List.map
+    (fun (r, g, b) -> (r /. 255., g /. 255., b /. 255.))
+    [
+      (74., 58., 59.);
+      (152., 65., 54.);
+      (194., 106., 122.);
+      (236., 192., 161.);
+      (240., 240., 228.);
+    ]
+
+let clamp = function
+  | n when n > size - 1 -> size - 1
+  | n when n < 0 -> 0
+  | n -> n
+
+let fclamp max = function f when f > max -> max | f when f < 0. -> 0. | f -> f
+
+let flowfield () =
+  Bigarray.Array2.init Bigarray.Float32 Bigarray.c_layout size size (fun x y ->
+      let noise =
+        fractal2 octaves
+          ((float_of_int x /. float_of_int size *. noise_scale) +. seed)
+          ((float_of_int y /. float_of_int size *. noise_scale) +. seed)
+      in
+      let uni = (noise *. 0.5) +. 0.5 in
+      fclamp tau uni *. tau)
+
+let grid divison =
+  let grid_size = size / divison in
+  let spacing = size / grid_size in
+  List.init (grid_size * grid_size) (fun i ->
+      (i / grid_size * spacing, i mod grid_size * spacing))
+
+let uni_to_bi (x, y) =
+  let x = x - (size / 2) in
+  let y = y - (size / 2) in
+  (float_of_int x, float_of_int y)
+
+let vector_of_angle angle =
+  ( sin angle |> Float.round |> int_of_float,
+    cos angle |> Float.round |> int_of_float )
+
+let rec step n (x, y) flowfield =
+  if n >= 0 then
+    let cx, cy = (clamp x, clamp y) in
+    let angle = Bigarray.Array2.get flowfield cx cy in
+    let dx, dy = vector_of_angle angle in
+    step (n - 1) (x + dx, y + dy) flowfield
+  else (x, y)
+
+let make_line flowfield (x, y) =
+  let cx, cy = (clamp x, clamp y) in
+  let angle = Bigarray.Array2.get flowfield cx cy in
+  let dx, dy = vector_of_angle angle in
+  let next = (x + dx, y + dy) in
+  let final = step num_steps next flowfield in
+  let ax, ay = uni_to_bi (x, y) in
+  let bx, by = uni_to_bi final in
+  (line ~a:(point ax ay) (point bx by), (cx, cy))
+
+let render_with_color flowfield line (x, y) =
+  let color_idx =
+    Bigarray.Array2.get flowfield x y /. tau
+    |> ( *. ) (float_of_int (List.length palette))
+    |> int_of_float
+  in
+  let _ = print_int color_idx in
+  let color = List.nth palette color_idx in
+  set_color color;
+  render line
+
+let () =
+  init ();
+  background (1., 1., 1., 1.);
+  let flowfield = flowfield () in
+  let interval = size / grid_divisor in
+  let indices = grid interval in
+  let lines, points = List.map (make_line flowfield) indices |> List.split in
+  let centered =
+    List.map (translate (float_of_int interval) (float_of_int interval)) lines
+  in
+  List.iter2 (render_with_color flowfield) centered points;
+  write ~filename:"flowfield.png" ()
diff --git a/examples/noise.ml b/examples/noise.ml
new file mode 100644
index 0000000..b8c6016
--- /dev/null
+++ b/examples/noise.ml
@@ -0,0 +1,124 @@
+open Base
+
+(* borrowed from
+   https://gist.githubusercontent.com/tjammer/509981fed4d50683cdb800da5bf16ab1/raw/da2b8cc86718ef7e93e2e2c707dcfe443809d7cc/simplex.ml *)
+let permutation =
+  [|
+    151; 160; 137; 91; 90; 15; 131; 13; 201; 95; 96; 53; 194; 233; 7; 225; 140;
+    36; 103; 30; 69; 142; 8; 99; 37; 240; 21; 10; 23; 190; 6; 148; 247; 120;
+    234; 75; 0; 26; 197; 62; 94; 252; 219; 203; 117; 35; 11; 32; 57; 177; 33;
+    88; 237; 149; 56; 87; 174; 20; 125; 136; 171; 168; 68; 175; 74; 165; 71;
+    134; 139; 48; 27; 166; 77; 146; 158; 231; 83; 111; 229; 122; 60; 211; 133;
+    230; 220; 105; 92; 41; 55; 46; 245; 40; 244; 102; 143; 54; 65; 25; 63; 161;
+    1; 216; 80; 73; 209; 76; 132; 187; 208; 89; 18; 169; 200; 196; 135; 130;
+    116; 188; 159; 86; 164; 100; 109; 198; 173; 186; 3; 64; 52; 217; 226; 250;
+    124; 123; 5; 202; 38; 147; 118; 126; 255; 82; 85; 212; 207; 206; 59; 227;
+    47; 16; 58; 17; 182; 189; 28; 42; 223; 183; 170; 213; 119; 248; 152; 2; 44;
+    154; 163; 70; 221; 153; 101; 155; 167; 43; 172; 9; 129; 22; 39; 253; 19; 98;
+    108; 110; 79; 113; 224; 232; 178; 185; 112; 104; 218; 246; 97; 228; 251; 34;
+    242; 193; 238; 210; 144; 12; 191; 179; 162; 241; 81; 51; 145; 235; 249; 14;
+    239; 107; 49; 192; 214; 31; 181; 199; 106; 157; 184; 84; 204; 176; 115; 121;
+    50; 45; 127; 4; 150; 254; 138; 236; 205; 93; 222; 114; 67; 29; 24; 72; 243;
+    141; 128; 195; 78; 66; 215; 61; 156; 180;
+  |]
+[@@ocamlformat "break-collection-expressions=wrap"]
+
+let hash n = permutation.(Int.of_float n land 255)
+
+let grad1 hash x =
+  let h = hash land 0x0F in
+  (* gradient value 1.0, 2.0 .. 8.0 *)
+  let grad = 1.0 +. Float.of_int (h land 7) in
+  let grad = if h land 8 <> 0 then -.grad else grad in
+  grad *. x
+
+let grad2 hash x y =
+  let h = hash land 0x3F in
+  let u, v = if h < 4 then (x, y) else (y, x) in
+  (if h land 1 <> 0 then -.u else u)
+  +. if h land 2 <> 0 then -2.0 *. v else 2.0 *. v
+
+let snoise1 x =
+  let i0 = Float.round_down x in
+  let i1 = i0 +. 1.0 in
+  let x0 = x -. i0 in
+  let x1 = x0 -. 1.0 in
+  let t0 = 1.0 -. (x0 *. x0) in
+  let t0 = t0 *. t0 in
+  let n0 = t0 *. t0 *. grad1 (hash i0) x0 in
+  let t1 = 1.0 -. (x1 *. x1) in
+  let t1 = t1 *. t1 in
+  let n1 = t1 *. t1 *. grad1 (hash i1) x1 in
+  (* The maximum value of this noise is 8*(3/4)^4 = 2.53125 *)
+  (* A factor of 0.395 scales to fit exactly within [-1,1] *)
+  0.395 *. (n0 +. n1)
+
+let snoise2 x y =
+  let _F2 = 0.366025403 in
+  (* F2 = (sqrt(3) - 1) / 2*)
+  let _G2 = 0.211324865 in
+  (*G2 = (3 - sqrt(3)) / 6 = F2 / (1 + 2 * K)*)
+  (* skew the input space to determine which simplex cell we're in *)
+  let s = (x +. y) *. _F2 in
+  let xs, ys = (x +. s, y +. s) in
+  let i, j = Float.(round_down xs, round_down ys) in
+  (* unskew the cell origin back to (x, y) space *)
+  let t = (i +. j) *. _G2 in
+  let _X0 = i -. t in
+  let _Y0 = j -. t in
+  let x0, y0 = (x -. _X0, y -. _Y0) in
+  (* determine which simplex we're in *)
+  let i1, j1 = if Poly.(x0 > y0) then (1., 0.) else (0., 1.) in
+  (* A step of (1,0) in (i,j) means a step of (1-c,-c) in (x,y), and *)
+  (* a step of (0,1) in (i,j) means a step of (-c,1-c) in (x,y), where *)
+  (* c = (3-sqrt(3))/6 *)
+  let x1, y1 = Float.(x0 - i1 + _G2, y0 - j1 + _G2) in
+  let x2, y2 = Float.(x0 - 1.0 + (2.0 * _G2), y0 - 1.0 + (2.0 * _G2)) in
+  (* Work out the hashed gradient indices of the three simplex corners *)
+  let gi0 = (j |> hash |> Float.of_int) +. i |> hash in
+  let gi1 = (j +. j1 |> hash |> Float.of_int) +. i +. i1 |> hash in
+  let gi2 = (j +. 1. |> hash |> Float.of_int) +. i +. 1. |> hash in
+  let contrib x y gi =
+    let t = 0.5 -. (x *. x) -. (y *. y) in
+    if Float.(t < 0.0) then 0.0
+    else
+      let t = t *. t in
+      t *. t *. grad2 gi x y
+  in
+  (* Calculate the contribution from the first corner *)
+  let n0 = contrib x0 y0 gi0 in
+  (* Calculate the contribution from the second corner *)
+  let n1 = contrib x1 y1 gi1 in
+  (* Calculate the contribution from the third corner *)
+  let n2 = contrib x2 y2 gi2 in
+  45.23065 *. (n0 +. n1 +. n2)
+
+(* constants *)
+let frequency = ref 1.0
+let amplitude = ref 1.0
+let lacunarity = ref 2.0
+let persistence = ref 0.5
+
+let fractal1 octaves x =
+  let rec loop noise amp i =
+    if i = 0 then noise /. amp
+    else
+      let frequency = !frequency *. Float.int_pow !lacunarity (i - 1) in
+      let amplitude = !amplitude *. Float.int_pow !persistence (i - 1) in
+      loop
+        (noise +. (amplitude *. snoise1 (x *. frequency)))
+        (amp +. amplitude) (i - 1)
+  in
+  loop 0.0 0.0 octaves
+
+let fractal2 octaves x y =
+  let rec loop noise amp i =
+    if i = 0 then noise /. amp
+    else
+      let frequency = !frequency *. Float.int_pow !lacunarity (i - 1) in
+      let amplitude = !amplitude *. Float.int_pow !persistence (i - 1) in
+      loop
+        (noise +. (amplitude *. snoise2 (x *. frequency) (y *. frequency)))
+        (amp +. amplitude) (i - 1)
+  in
+  loop 0.0 0.0 octaves
diff --git a/examples/noise.mli b/examples/noise.mli
new file mode 100644
index 0000000..af1455a
--- /dev/null
+++ b/examples/noise.mli
@@ -0,0 +1,12 @@
+val permutation : int array
+val hash : float -> int
+val grad1 : int -> float -> float
+val grad2 : int -> float -> float -> float
+val snoise1 : float -> float
+val snoise2 : float -> float -> float
+val frequency : float ref
+val amplitude : float ref
+val lacunarity : float ref
+val persistence : float ref
+val fractal1 : int -> float -> float
+val fractal2 : int -> float -> float -> float
diff --git a/lib/shape.ml b/lib/shape.ml
index b47b594..d6f7089 100644
--- a/lib/shape.ml
+++ b/lib/shape.ml
@@ -41,10 +41,14 @@ let rectangle ?(c = center) width height =
       { x = x1 +. w; y = y1 };
     ]
 
+<<<<<<< HEAD
 let ellipse ?(c = center) rx ry =
   let rx, ry = (float_of_int rx, float_of_int ry) in
   Ellipse { c; rx; ry }
 
+=======
+let ellipse ?(c = center) rx ry = Ellipse { c; rx; ry }
+>>>>>>> 7ad720e (added flowfield example, dune fmt)
 let line ?(a = center) b = Line { a; b }
 let polygon lst_points = Polygon lst_points
 

From d403b072aab1a1c91d2da47b3daf08c8569ada23 Mon Sep 17 00:00:00 2001
From: Fay Carsons <faycarsons23@gmail.com>
Date: Mon, 22 Jan 2024 21:23:14 -0500
Subject: [PATCH 2/5] fixed random seeding issue, switched line list to array,
 fmt

---
 examples/flowfield.ml | 44 +++++++++++++++++++++++++++++--------------
 1 file changed, 30 insertions(+), 14 deletions(-)

diff --git a/examples/flowfield.ml b/examples/flowfield.ml
index 4c726e3..a6fa592 100644
--- a/examples/flowfield.ml
+++ b/examples/flowfield.ml
@@ -1,14 +1,20 @@
-open Noise
 open Joy
 
-let size = 800
+(* Constants *)
+let size = 1200
 let tau = 2. *. Float.pi
-let num_steps = 8
-let grid_divisor = 64
-let octaves = 6
-let noise_scale = 4.
-let _ = Stdlib.Random.self_init
-let seed = Stdlib.Random.float 1000.
+let num_steps = 12
+let grid_divisor = 256
+let _ = Random.self_init ()
+let octaves = 4
+let noise_scale = 2. +. Random.float 3.
+
+(* Utilities & color palette *)
+
+let shuffle xs =
+  let nd = List.map (fun c -> (Random.bits (), c)) xs in
+  let sond = List.sort compare nd in
+  List.map snd sond
 
 let palette =
   List.map
@@ -20,6 +26,7 @@ let palette =
       (236., 192., 161.);
       (240., 240., 228.);
     ]
+  |> shuffle
 
 let clamp = function
   | n when n > size - 1 -> size - 1
@@ -28,31 +35,38 @@ let clamp = function
 
 let fclamp max = function f when f > max -> max | f when f < 0. -> 0. | f -> f
 
+(* Initialize flowfield, a large 2D array containing angles determined by
+   seeded simplex noise sampled at each coordinate *)
 let flowfield () =
+  let seed = Random.float 100. in
   Bigarray.Array2.init Bigarray.Float32 Bigarray.c_layout size size (fun x y ->
       let noise =
-        fractal2 octaves
+        Noise.fractal2 octaves
           ((float_of_int x /. float_of_int size *. noise_scale) +. seed)
           ((float_of_int y /. float_of_int size *. noise_scale) +. seed)
       in
       let uni = (noise *. 0.5) +. 0.5 in
       fclamp tau uni *. tau)
 
+(* Create a n*n grid of points where lines will be placed *)
 let grid divison =
   let grid_size = size / divison in
   let spacing = size / grid_size in
-  List.init (grid_size * grid_size) (fun i ->
+  Array.init (grid_size * grid_size) (fun i ->
       (i / grid_size * spacing, i mod grid_size * spacing))
 
+(* scale 0-n coordinates to [-n/2..n/2] *)
 let uni_to_bi (x, y) =
   let x = x - (size / 2) in
   let y = y - (size / 2) in
   (float_of_int x, float_of_int y)
 
+(* Create a 2D vector from an angle *)
 let vector_of_angle angle =
   ( sin angle |> Float.round |> int_of_float,
     cos angle |> Float.round |> int_of_float )
 
+(* Step along the flowfield, following the angles at each point visited *)
 let rec step n (x, y) flowfield =
   if n >= 0 then
     let cx, cy = (clamp x, clamp y) in
@@ -61,6 +75,7 @@ let rec step n (x, y) flowfield =
     step (n - 1) (x + dx, y + dy) flowfield
   else (x, y)
 
+(* Given a coordinate, draws a line starting at that point, following flowfield *)
 let make_line flowfield (x, y) =
   let cx, cy = (clamp x, clamp y) in
   let angle = Bigarray.Array2.get flowfield cx cy in
@@ -71,13 +86,13 @@ let make_line flowfield (x, y) =
   let bx, by = uni_to_bi final in
   (line ~a:(point ax ay) (point bx by), (cx, cy))
 
+(* Renders line with color based on its angle *)
 let render_with_color flowfield line (x, y) =
   let color_idx =
     Bigarray.Array2.get flowfield x y /. tau
     |> ( *. ) (float_of_int (List.length palette))
     |> int_of_float
   in
-  let _ = print_int color_idx in
   let color = List.nth palette color_idx in
   set_color color;
   render line
@@ -85,12 +100,13 @@ let render_with_color flowfield line (x, y) =
 let () =
   init ();
   background (1., 1., 1., 1.);
+  set_line_width 0.0005;
   let flowfield = flowfield () in
   let interval = size / grid_divisor in
   let indices = grid interval in
-  let lines, points = List.map (make_line flowfield) indices |> List.split in
+  let lines, points = Array.map (make_line flowfield) indices |> Array.split in
   let centered =
-    List.map (translate (float_of_int interval) (float_of_int interval)) lines
+    Array.map (translate (float_of_int interval) (float_of_int interval)) lines
   in
-  List.iter2 (render_with_color flowfield) centered points;
+  Array.iter2 (render_with_color flowfield) centered points;
   write ~filename:"flowfield.png" ()

From 49922426ee2bc78bb59daff12c8adac07c6d2071 Mon Sep 17 00:00:00 2001
From: Fay Carsons <faycarsons23@gmail.com>
Date: Fri, 2 Feb 2024 11:46:33 -0500
Subject: [PATCH 3/5] migrate to int api

---
 examples/flowfield.ml | 38 ++++++++++++++++++--------------------
 lib/shape.ml          |  4 ----
 2 files changed, 18 insertions(+), 24 deletions(-)

diff --git a/examples/flowfield.ml b/examples/flowfield.ml
index a6fa592..0678512 100644
--- a/examples/flowfield.ml
+++ b/examples/flowfield.ml
@@ -1,30 +1,27 @@
-open Joy
-
 (* Constants *)
 let size = 1200
 let tau = 2. *. Float.pi
-let num_steps = 12
-let grid_divisor = 256
+let num_steps = 6
+let grid_divisor = 128
 let _ = Random.self_init ()
 let octaves = 4
 let noise_scale = 2. +. Random.float 3.
 
 (* Utilities & color palette *)
 
+(* Randomly shuffles a list *)
 let shuffle xs =
-  let nd = List.map (fun c -> (Random.bits (), c)) xs in
-  let sond = List.sort compare nd in
-  List.map snd sond
+  let pairs = List.map (fun c -> (Random.bits (), c)) xs in
+  let sorted = List.sort compare pairs in
+  List.map snd sorted
 
 let palette =
-  List.map
-    (fun (r, g, b) -> (r /. 255., g /. 255., b /. 255.))
     [
-      (74., 58., 59.);
-      (152., 65., 54.);
-      (194., 106., 122.);
-      (236., 192., 161.);
-      (240., 240., 228.);
+      (74, 58, 59);
+      (152, 65, 54);
+      (194, 106, 122);
+      (236, 192, 161);
+      (240, 240, 228);
     ]
   |> shuffle
 
@@ -84,7 +81,7 @@ let make_line flowfield (x, y) =
   let final = step num_steps next flowfield in
   let ax, ay = uni_to_bi (x, y) in
   let bx, by = uni_to_bi final in
-  (line ~a:(point ax ay) (point bx by), (cx, cy))
+  (Joy.line ~a:{x = ax;y = ay} {x = bx; y = by}, (cx, cy))
 
 (* Renders line with color based on its angle *)
 let render_with_color flowfield line (x, y) =
@@ -94,19 +91,20 @@ let render_with_color flowfield line (x, y) =
     |> int_of_float
   in
   let color = List.nth palette color_idx in
-  set_color color;
-  render line
+  Joy.set_color color;
+  Joy.render line
 
 let () =
+  let open Joy in
   init ();
-  background (1., 1., 1., 1.);
-  set_line_width 0.0005;
+  background (255, 255, 255, 255);
+  set_line_width 3;
   let flowfield = flowfield () in
   let interval = size / grid_divisor in
   let indices = grid interval in
   let lines, points = Array.map (make_line flowfield) indices |> Array.split in
   let centered =
-    Array.map (translate (float_of_int interval) (float_of_int interval)) lines
+    Array.map (translate interval interval) lines
   in
   Array.iter2 (render_with_color flowfield) centered points;
   write ~filename:"flowfield.png" ()
diff --git a/lib/shape.ml b/lib/shape.ml
index d6f7089..b47b594 100644
--- a/lib/shape.ml
+++ b/lib/shape.ml
@@ -41,14 +41,10 @@ let rectangle ?(c = center) width height =
       { x = x1 +. w; y = y1 };
     ]
 
-<<<<<<< HEAD
 let ellipse ?(c = center) rx ry =
   let rx, ry = (float_of_int rx, float_of_int ry) in
   Ellipse { c; rx; ry }
 
-=======
-let ellipse ?(c = center) rx ry = Ellipse { c; rx; ry }
->>>>>>> 7ad720e (added flowfield example, dune fmt)
 let line ?(a = center) b = Line { a; b }
 let polygon lst_points = Polygon lst_points
 

From 1d7d6a0842fe41a339391cf3c7dba52a57411a59 Mon Sep 17 00:00:00 2001
From: Fay Carsons <faycarsons23@gmail.com>
Date: Tue, 27 Feb 2024 14:07:06 -0500
Subject: [PATCH 4/5] update flowfield.ml to new API

---
 examples/flowfield.ml | 23 +++++++++++------------
 1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/examples/flowfield.ml b/examples/flowfield.ml
index 0678512..906f56d 100644
--- a/examples/flowfield.ml
+++ b/examples/flowfield.ml
@@ -49,7 +49,7 @@ let flowfield () =
 let grid divison =
   let grid_size = size / divison in
   let spacing = size / grid_size in
-  Array.init (grid_size * grid_size) (fun i ->
+  List.init (grid_size * grid_size) (fun i ->
       (i / grid_size * spacing, i mod grid_size * spacing))
 
 (* scale 0-n coordinates to [-n/2..n/2] *)
@@ -83,28 +83,27 @@ let make_line flowfield (x, y) =
   let bx, by = uni_to_bi final in
   (Joy.line ~a:{x = ax;y = ay} {x = bx; y = by}, (cx, cy))
 
-(* Renders line with color based on its angle *)
-let render_with_color flowfield line (x, y) =
-  let color_idx =
-    Bigarray.Array2.get flowfield x y /. tau
+(* Adds color to line, based on its angle *)
+let add_color flowfield line (x, y) = 
+  let color = 
+    Bigarray.Array2.get flowfield x y /. tau 
     |> ( *. ) (float_of_int (List.length palette))
     |> int_of_float
+    |> List.nth palette 
   in
-  let color = List.nth palette color_idx in
-  Joy.set_color color;
-  Joy.render line
+  line |> Joy.with_stroke color 
 
 let () =
   let open Joy in
   init ();
-  background (255, 255, 255, 255);
   set_line_width 3;
   let flowfield = flowfield () in
   let interval = size / grid_divisor in
   let indices = grid interval in
-  let lines, points = Array.map (make_line flowfield) indices |> Array.split in
+  let lines, points = List.map (make_line flowfield) indices |> List.split in
   let centered =
-    Array.map (translate interval interval) lines
+    List.map (translate interval interval) lines
   in
-  Array.iter2 (render_with_color flowfield) centered points;
+  let lines = List.map2 (add_color flowfield) centered points in 
+  show lines;
   write ~filename:"flowfield.png" ()

From 1b3f42e21ad82bdbf06274b42193c8a51ada6d0e Mon Sep 17 00:00:00 2001
From: Fay Carsons <faycarsons23@gmail.com>
Date: Tue, 27 Feb 2024 14:09:14 -0500
Subject: [PATCH 5/5] fmt

---
 examples/circle_packing.ml |  4 +---
 examples/dune              |  2 +-
 examples/flowfield.ml      | 33 +++++++++++++++------------------
 lib/joy.ml                 |  5 ++---
 lib/render.ml              |  7 ++-----
 5 files changed, 21 insertions(+), 30 deletions(-)

diff --git a/examples/circle_packing.ml b/examples/circle_packing.ml
index e94d733..4b20e27 100644
--- a/examples/circle_packing.ml
+++ b/examples/circle_packing.ml
@@ -94,9 +94,7 @@ let () =
   let circles =
     List.map
       (fun ((x, y), radius) ->
-        circle
-          ~c:{x; y}
-          (int_of_float radius)
+        circle ~c:{ x; y } (int_of_float radius)
         |> with_stroke (rand_nth palette))
       concentric
   in
diff --git a/examples/dune b/examples/dune
index b3a8ec1..139ec32 100644
--- a/examples/dune
+++ b/examples/dune
@@ -103,7 +103,7 @@
  (modules donut_with_scale)
  (libraries joy))
 
-(executable 
+(executable
  (name flowfield)
  (modules flowfield noise)
  (libraries joy base))
diff --git a/examples/flowfield.ml b/examples/flowfield.ml
index 906f56d..6903b4f 100644
--- a/examples/flowfield.ml
+++ b/examples/flowfield.ml
@@ -16,13 +16,13 @@ let shuffle xs =
   List.map snd sorted
 
 let palette =
-    [
-      (74, 58, 59);
-      (152, 65, 54);
-      (194, 106, 122);
-      (236, 192, 161);
-      (240, 240, 228);
-    ]
+  [
+    (74, 58, 59);
+    (152, 65, 54);
+    (194, 106, 122);
+    (236, 192, 161);
+    (240, 240, 228);
+  ]
   |> shuffle
 
 let clamp = function
@@ -81,17 +81,16 @@ let make_line flowfield (x, y) =
   let final = step num_steps next flowfield in
   let ax, ay = uni_to_bi (x, y) in
   let bx, by = uni_to_bi final in
-  (Joy.line ~a:{x = ax;y = ay} {x = bx; y = by}, (cx, cy))
+  (Joy.line ~a:{ x = ax; y = ay } { x = bx; y = by }, (cx, cy))
 
 (* Adds color to line, based on its angle *)
-let add_color flowfield line (x, y) = 
-  let color = 
-    Bigarray.Array2.get flowfield x y /. tau 
+let add_color flowfield line (x, y) =
+  let color =
+    Bigarray.Array2.get flowfield x y /. tau
     |> ( *. ) (float_of_int (List.length palette))
-    |> int_of_float
-    |> List.nth palette 
+    |> int_of_float |> List.nth palette
   in
-  line |> Joy.with_stroke color 
+  line |> Joy.with_stroke color
 
 let () =
   let open Joy in
@@ -101,9 +100,7 @@ let () =
   let interval = size / grid_divisor in
   let indices = grid interval in
   let lines, points = List.map (make_line flowfield) indices |> List.split in
-  let centered =
-    List.map (translate interval interval) lines
-  in
-  let lines = List.map2 (add_color flowfield) centered points in 
+  let centered = List.map (translate interval interval) lines in
+  let lines = List.map2 (add_color flowfield) centered points in
   show lines;
   write ~filename:"flowfield.png" ()
diff --git a/lib/joy.ml b/lib/joy.ml
index b6eb36a..a48308c 100644
--- a/lib/joy.ml
+++ b/lib/joy.ml
@@ -36,9 +36,8 @@ let set_line_width = Context.set_line_width
 
 let init ?(background = Color.white) ?(line_width = 2) ?(size = (500, 500))
     ?(axes = false) () =
-  Context.init_context (Color.opaque background)
-    (float_of_int line_width)
-    size axes
+  Context.init_context (Color.opaque background) (float_of_int line_width) size
+    axes
 
 let write ?(filename = "joy.png") () =
   match !Context.context with
diff --git a/lib/render.ml b/lib/render.ml
index eca4a77..fdf029b 100644
--- a/lib/render.ml
+++ b/lib/render.ml
@@ -17,7 +17,7 @@ let draw_circle ctx ({ c; radius; stroke; fill } : circle) =
   Option.iter fill_circle fill;
   Cairo.Path.clear ctx.ctx
 
-let create_control_points ({x; y}, rx, ry) =
+let create_control_points ({ x; y }, rx, ry) =
   let half_height = ry /. 2. in
   let width_two_thirds = rx *. (2. /. 3.) *. 2. in
   ( { x; y = y -. half_height },
@@ -74,10 +74,7 @@ let rec partition n ?(step = 0) lst =
   | [] -> []
   | _ ->
       let taken, _ = take n lst in
-      if List.length taken = n then
-        taken
-        ::
-        partition n ~step (List.tl lst)
+      if List.length taken = n then taken :: partition n ~step (List.tl lst)
       else []
 
 let draw_polygon ctx { vertices = points; stroke; fill } =