From bf4b1bec6c3e5819fb949d9b076495b239ae7860 Mon Sep 17 00:00:00 2001
From: Kaustubh Maske Patil <37668193+nikochiko@users.noreply.github.com>
Date: Tue, 12 Mar 2024 11:07:44 +0530
Subject: [PATCH 1/9] Refactor and rename: backends, cairo, contexts

---
 examples/axes.ml           |   2 -
 examples/circle_packing.ml |  14 ++---
 examples/fill_rect.ml      |   3 +-
 examples/flowfield.ml      |   3 +-
 examples/quadtree.ml       |   4 +-
 examples/square.ml         |   2 +-
 lib/backend_cairo.ml       | 104 ++++++++++++++++++++++++++++++
 lib/backend_cairo.mli      |  15 +++++
 lib/backend_lazy.ml        |   5 ++
 lib/backend_lazy.mli       |   4 ++
 lib/backend_svg.ml         |   4 ++
 lib/backend_svg.mli        |   4 ++
 lib/color.ml               |  28 ++++-----
 lib/color.mli              |   7 ++-
 lib/context.ml             | 125 ++++++++++++++++---------------------
 lib/context.mli            |  31 +++++----
 lib/joy.ml                 |  28 ++++++---
 lib/joy.mli                |  40 ++++++------
 lib/render.ml              |  89 --------------------------
 lib/render.mli             |   6 --
 lib/shape.ml               |  57 ++++++-----------
 lib/shape.mli              |  14 ++---
 lib/transform.ml           |  12 ++--
 23 files changed, 308 insertions(+), 293 deletions(-)
 create mode 100644 lib/backend_cairo.ml
 create mode 100644 lib/backend_cairo.mli
 create mode 100644 lib/backend_lazy.ml
 create mode 100644 lib/backend_lazy.mli
 create mode 100644 lib/backend_svg.ml
 create mode 100644 lib/backend_svg.mli
 delete mode 100644 lib/render.ml
 delete mode 100644 lib/render.mli

diff --git a/examples/axes.ml b/examples/axes.ml
index aa8c2ef..c12bbc5 100644
--- a/examples/axes.ml
+++ b/examples/axes.ml
@@ -2,9 +2,7 @@
 open Joy
 
 let _ =
-  (* intialize rendering context with the axes flag set to true *)
   init ~axes:true ();
-  (* set background to opaque white *)
   let c = circle 50 in
   show [ c ];
   (* Write to PNG! *)
diff --git a/examples/circle_packing.ml b/examples/circle_packing.ml
index a954639..fc3670b 100644
--- a/examples/circle_packing.ml
+++ b/examples/circle_packing.ml
@@ -16,19 +16,19 @@ let max_attempts = 100_000
 let palette =
   [
     (* purple *)
-    (107, 108, 163);
+    rgb 107 108 163;
     (* light blue *)
-    (135, 188, 189);
+    rgb 135 188 189;
     (* green *)
-    (111, 153, 84);
+    rgb 111 153 84;
     (* light purple *)
-    (150, 155, 199);
+    rgb 150 155 199;
     (* light green *)
-    (137, 171, 124);
+    rgb 137 171 124;
     (* dark purple *)
-    (67, 68, 117);
+    rgb 67 68 117;
     (* darker purple *)
-    (44, 45, 84);
+    rgb 44 45 84;
   ]
 
 (* utility Functions *)
diff --git a/examples/fill_rect.ml b/examples/fill_rect.ml
index 18d5b28..5ca19b3 100644
--- a/examples/fill_rect.ml
+++ b/examples/fill_rect.ml
@@ -2,6 +2,7 @@ open Joy
 
 let () =
   init ();
-  let r = rectangle 200 200 |> with_fill (255, 0, 0) in
+  let r = rectangle 200 200 |> with_fill (rgb 255 0 0) in
   show [ r ];
   write ~filename:"fill-rect.png" ()
+
diff --git a/examples/flowfield.ml b/examples/flowfield.ml
index e857ca3..4b05d0a 100644
--- a/examples/flowfield.ml
+++ b/examples/flowfield.ml
@@ -91,7 +91,8 @@ let add_color flowfield line (x, y) =
     |> ( *. ) (float_of_int (List.length palette))
     |> int_of_float |> List.nth palette
   in
-  line |> Joy.with_stroke color
+  let r, g, b = color in
+  line |> Joy.with_stroke (Joy.rgb r g b)
 
 let () =
   let open Joy in
diff --git a/examples/quadtree.ml b/examples/quadtree.ml
index 59936a0..f0c2d54 100644
--- a/examples/quadtree.ml
+++ b/examples/quadtree.ml
@@ -6,8 +6,8 @@ let half_size = size /. 2.
 let max_leaf_points = 4
 let clusters = 32
 let point_size = 1
-let box_color = (0, 0, 0)
-let point_color = (255, 1, 1)
+let box_color = Joy.rgb 0 0 0
+let point_color = Joy.rgb 255 1 1
 
 (* Point utils *)
 let splat n : point = { x = n; y = n }
diff --git a/examples/square.ml b/examples/square.ml
index 542788c..9c68a08 100644
--- a/examples/square.ml
+++ b/examples/square.ml
@@ -1,7 +1,7 @@
 open Joy
 
 let () =
-  init ();
+  init ~axes:true ();
   let square = rectangle 100 100 in
   show [ square ];
   write ~filename:"square.png" ()
diff --git a/lib/backend_cairo.ml b/lib/backend_cairo.ml
new file mode 100644
index 0000000..336feac
--- /dev/null
+++ b/lib/backend_cairo.ml
@@ -0,0 +1,104 @@
+type context = {
+  cairo_ctx : Cairo.context;
+  surface : Cairo.Surface.t;
+  size : int * int;
+  background_color: int * int * int * float;
+  axes: bool;
+}
+
+let write ctx filename =
+  Cairo.PNG.write ctx.surface filename;
+  Cairo.Surface.finish ctx.surface
+
+let set_color ctx color =
+  let to_float i = (float_of_int i) /. 255. in
+  let r, g, b, a = color in
+  let r, g, b = Util.tmap3 to_float (r, g, b) in
+  Cairo.set_source_rgba ctx.cairo_ctx r g b a
+
+let set_background ctx color =
+  let r, g, b, a = color in
+  let to_float i = (float_of_int i) /. 255. in
+  let r, g, b = Util.tmap3 to_float (r, g, b) in
+  Cairo.set_source_rgba ctx.cairo_ctx r g b a;
+  Cairo.paint ctx.cairo_ctx ~alpha:a;
+  Cairo.fill ctx.cairo_ctx
+
+(** Sets the width of lines for both stroke of shapes and line primitives. 
+    Can be any positive integer, with larger numbers producing thicker lines. 
+    default is 2 *)
+let set_line_width ctx line_width =
+  Cairo.set_line_width ctx.cairo_ctx (float_of_int line_width)
+
+let draw_circle ctx (cx, cy) radius stroke fill =
+  (* TODO: stroke and fill MUST have a value before coming to the renderer *)
+  Cairo.arc ctx.cairo_ctx cx (Float.neg cy) ~r:radius ~a1:0. ~a2:(Float.pi *. 2.);
+  set_color ctx stroke;
+  Cairo.stroke_preserve ctx.cairo_ctx;
+  set_color ctx fill;
+  Cairo.fill_preserve ctx.cairo_ctx;
+  Cairo.Path.clear ctx.cairo_ctx
+
+let draw_ellipse ctx (cx, cy) rx ry stroke fill =
+  (* Save the current transformation matrix *)
+  let save_matrix = Cairo.get_matrix ctx.cairo_ctx in
+
+  (* Translate and scale to create an ellipse from a circle *)
+  Cairo.translate ctx.cairo_ctx cx (Float.neg cy);
+  Cairo.scale ctx.cairo_ctx rx ry;
+  Cairo.arc ctx.cairo_ctx 0. 0. ~r:1. ~a1:0. ~a2:(2. *. Float.pi);
+
+  (* Restore the original transformation matrix *)
+  Cairo.set_matrix ctx.cairo_ctx save_matrix;
+
+  set_color ctx stroke;
+  Cairo.stroke_preserve ctx.cairo_ctx;
+  set_color ctx fill;
+  Cairo.fill_preserve ctx.cairo_ctx;
+
+  Cairo.Path.clear ctx.cairo_ctx
+
+let draw_line ctx (x1, y1) (x2, y2) stroke =
+  set_color ctx stroke;
+  Cairo.move_to ctx.cairo_ctx x1 (Float.neg y1);
+  Cairo.line_to ctx.cairo_ctx x2 (Float.neg y2);
+  Cairo.stroke ctx.cairo_ctx
+
+let draw_polygon ctx vertices stroke fill =
+  let x, y = List.hd vertices in
+  let t = List.tl vertices in
+  Cairo.move_to ctx.cairo_ctx x (Float.neg y);
+  List.iter
+    (fun (x', y') -> Cairo.line_to ctx.cairo_ctx x' (Float.neg y'))
+    t;
+  Cairo.Path.close ctx.cairo_ctx;
+  set_color ctx stroke;
+  Cairo.stroke_preserve ctx.cairo_ctx;
+  set_color ctx fill;
+  Cairo.fill ctx.cairo_ctx
+
+let show ctx shapes =
+  let rec render = function
+    | Shape.Circle circle -> (
+      draw_circle ctx (circle.c.x, circle.c.y) circle.radius circle.stroke circle.fill
+    )
+    | Shape.Ellipse ellipse -> draw_ellipse ctx (ellipse.c.x, ellipse.c.y) ellipse.rx ellipse.ry ellipse.stroke ellipse.fill
+    | Shape.Line line -> draw_line ctx (line.a.x, line.a.y) (line.b.x, line.b.y) line.stroke
+    | Shape.Polygon polygon -> (
+      let to_tuple (point: float Shape.point) = (point.x, point.y) in
+      draw_polygon ctx (List.map to_tuple polygon.vertices) polygon.stroke polygon.fill
+    )
+    | Shape.Complex complex -> List.iter render complex
+  in
+  List.iter render shapes
+
+let create ~background_color ~line_width ~size ~axes =
+  let w, h = size in
+  let surface = Cairo.Image.create Cairo.Image.ARGB32 ~w ~h in
+  let cairo_ctx = Cairo.create surface in
+  Cairo.translate cairo_ctx (w / 2 |> float_of_int) (h / 2 |> float_of_int);
+  let ctx = { cairo_ctx; surface; size = (w, h); background_color; axes } in
+  set_background ctx background_color;
+  set_line_width ctx line_width;
+  ctx
+
diff --git a/lib/backend_cairo.mli b/lib/backend_cairo.mli
new file mode 100644
index 0000000..3a67e8f
--- /dev/null
+++ b/lib/backend_cairo.mli
@@ -0,0 +1,15 @@
+type context = {
+  cairo_ctx : Cairo.context;
+  surface : Cairo.Surface.t;
+  size : int * int;
+  background_color: Color.color;
+  axes: bool;
+}
+
+val set_color : context -> Color.color -> unit
+val set_background : context -> Color.color -> unit
+val set_line_width : context -> int -> unit
+val show : context -> Shape.shapes -> unit
+val write : context -> string -> unit
+
+val create : background_color:Color.color -> line_width:int -> size:int * int -> axes:bool -> context
diff --git a/lib/backend_lazy.ml b/lib/backend_lazy.ml
new file mode 100644
index 0000000..e2d719e
--- /dev/null
+++ b/lib/backend_lazy.ml
@@ -0,0 +1,5 @@
+type context = unit
+
+let show _ctx _shapes = ()
+let create _ = ()
+
diff --git a/lib/backend_lazy.mli b/lib/backend_lazy.mli
new file mode 100644
index 0000000..d7ff084
--- /dev/null
+++ b/lib/backend_lazy.mli
@@ -0,0 +1,4 @@
+type context = unit
+
+val show : context -> Shape.shapes -> unit
+val create : unit -> context
diff --git a/lib/backend_svg.ml b/lib/backend_svg.ml
new file mode 100644
index 0000000..e0c304c
--- /dev/null
+++ b/lib/backend_svg.ml
@@ -0,0 +1,4 @@
+type context = unit
+
+let show _ctx _shapes = ()
+let create _ = ()
diff --git a/lib/backend_svg.mli b/lib/backend_svg.mli
new file mode 100644
index 0000000..d7ff084
--- /dev/null
+++ b/lib/backend_svg.mli
@@ -0,0 +1,4 @@
+type context = unit
+
+val show : context -> Shape.shapes -> unit
+val create : unit -> context
diff --git a/lib/color.ml b/lib/color.ml
index 18a8caa..0b5838b 100644
--- a/lib/color.ml
+++ b/lib/color.ml
@@ -1,26 +1,26 @@
-type color = int * int * int
+type color = int * int * int * float
+
+(** RGBA constant to set transparent background *)
+let transparent = (0, 0, 0, 0.0)
+
+(** Converts RGB color into opaque RGBA color. 
+    For use w/ `Context.background` *)
+let rgb r g b = (r, g, b, 1.0)
 
 (** RGB code for black *)
-let black = (0, 0, 0)
+let black = rgb 0 0 0
 
 (** RGB code for white *)
-let white = (255, 255, 255)
+let white = rgb 255 255 255
 
 (** RGB code for red *)
-let red = (255, 1, 1)
+let red = rgb 255 1 1
 
 (** RGB code for green *)
-let green = (1, 255, 1)
+let green = rgb 1 255 1
 
 (** RGB code for blue *)
-let blue = (1, 1, 255)
+let blue = rgb 1 1 255
 
 (** RGB code for yellow *)
-let yellow = (255, 255, 1)
-
-(** RGBA constant to set transparent background *)
-let transparent = (0, 0, 0, 0)
-
-(** Converts RGB color into opaque RGBA color. 
-    For use w/ `Context.background` *)
-let opaque (r, g, b) = (r, g, b, 255)
+let yellow = rgb 255 255 255
diff --git a/lib/color.mli b/lib/color.mli
index 7ac3165..0e0496b 100644
--- a/lib/color.mli
+++ b/lib/color.mli
@@ -1,4 +1,6 @@
-type color = int * int * int
+type color = int * int * int * float
+
+val rgb : int -> int -> int -> color
 
 val black : color
 val white : color
@@ -6,5 +8,4 @@ val red : color
 val green : color
 val blue : color
 val yellow : color
-val transparent : int * int * int * int
-val opaque : color -> int * int * int * int
+val transparent : color
diff --git a/lib/context.ml b/lib/context.ml
index f380448..6fcc83d 100644
--- a/lib/context.ml
+++ b/lib/context.ml
@@ -1,71 +1,56 @@
-open Util
+type context =
+    CairoContext of Backend_cairo.context
+  | SVGContext of Backend_svg.context
+  | LazyContext of Backend_lazy.context
+
+exception No_context
+exception Unsupported_output_format of string
+
+let default = ref (LazyContext (Backend_lazy.create ()))
+
+let get_default _ =
+  !default
+
+let set_default ctx =
+  default := ctx
+
+let show ?ctx shapes =
+  let ctx = match ctx with
+    | Some ctx -> ctx
+    | None -> get_default ()
+  in
+  match ctx with
+  | CairoContext ctx -> Backend_cairo.show ctx shapes
+  | SVGContext ctx -> Backend_svg.show ctx shapes
+  | LazyContext ctx -> Backend_lazy.show ctx shapes
+
+let set_line_width ?ctx int =
+  let ctx = match ctx with
+  | Some ctx -> ctx
+  | None -> get_default ()
+  in
+  match ctx with
+  | CairoContext ctx -> Backend_cairo.set_line_width ctx int
+  | SVGContext _ -> failwith "SVG.set_line_width ctx int"
+  | LazyContext _ -> failwith "Backend_lazy.set_line_width ctx int"
+
+let writePNG ?ctx filename =
+  let ctx = match ctx with
+    | Some ctx -> ctx
+    | None -> get_default ()
+  in
+  match ctx with
+  | CairoContext ctx -> Backend_cairo.write ctx filename
+  | SVGContext _ -> raise (Unsupported_output_format "SVG context cannot render to PNG")
+  | LazyContext _ -> failwith "Lazy.writePNG ctx filename"
+
+let writeSVG ?ctx =
+  let ctx = match ctx with
+    | Some ctx -> ctx
+    | None -> get_default ()
+  in
+  match ctx with
+  | CairoContext _ -> raise (Unsupported_output_format "Cairo context cannot render to SVG")
+  | SVGContext _ -> failwith "SVG.writeSVG ctx"
+  | LazyContext _ -> failwith "Lazy.writeSVG ctx"
 
-(* Global rendering context singleton definition and instantiation *)
-type context = {
-  ctx : Cairo.context;
-  surface : Cairo.Surface.t;
-  size : int * int;
-  axes : bool;
-}
-
-(* Renders context to PNG *)
-let write ctx filename =
-  Cairo.PNG.write ctx.surface filename;
-  Cairo.Surface.finish ctx.surface
-
-let context = ref None
-
-exception Context of string
-
-(* Not working, could use help fixing *)
-let () =
-  Printexc.register_printer (fun e ->
-      match e with Context err -> Some ("Context: " ^ err) | _ -> None)
-
-let fail () = raise (Context "not initialized")
-let resolution () = match !context with Some ctx -> ctx.size | None -> fail ()
-let scale_channel n = n /. 255.
-let scale_color_channel = float_of_int >> scale_channel
-
-let set_color color =
-  match !context with
-  | Some ctx ->
-      let r, g, b = tmap3 scale_color_channel color in
-      Cairo.set_source_rgb ctx.ctx r g b
-  | None -> fail ()
-
-(* sets background color *)
-let background color =
-  match !context with
-  | Some { ctx; _ } ->
-      let r, g, b, alpha = tmap4 scale_color_channel color in
-      Cairo.set_source_rgb ctx r g b;
-      Cairo.paint ctx ~alpha;
-      Cairo.fill ctx
-  | None -> fail ()
-
-(** Sets the width of lines for both stroke of shapes and line primitives. 
-    Can be any positive integer, with larger numbers producing thicker lines. 
-    default is 2 *)
-let set_line_width line_width =
-  match !context with
-  | Some ctx -> Cairo.set_line_width ctx.ctx (float_of_int line_width)
-  | None -> fail ()
-
-let save () =
-  match !context with Some ctx -> Cairo.save ctx.ctx | None -> fail ()
-
-let restore () =
-  match !context with Some ctx -> Cairo.restore ctx.ctx | None -> fail ()
-
-let init_context background_color line_width (w, h) axes =
-  (* Fail if context has already been instantiated *)
-  if Option.is_some !context then
-    raise (Context "Cannot initialize context twice");
-
-  let surface = Cairo.Image.create Cairo.Image.ARGB32 ~w ~h in
-  let ctx = Cairo.create surface in
-  Cairo.set_line_width ctx line_width;
-  Cairo.translate ctx (w / 2 |> float_of_int) (h / 2 |> float_of_int);
-  context := Some { ctx; surface; size = (w, h); axes };
-  background background_color
diff --git a/lib/context.mli b/lib/context.mli
index d9f36a9..01b57ec 100644
--- a/lib/context.mli
+++ b/lib/context.mli
@@ -1,20 +1,17 @@
-type context = {
-  ctx : Cairo.context;
-  surface : Cairo.Surface.t;
-  size : int * int;
-  axes : bool;
-}
+type context =
+    CairoContext of Backend_cairo.context
+  | SVGContext of Backend_svg.context
+  | LazyContext of Backend_lazy.context
 
-val context : context option ref
-val fail : unit -> unit
+exception No_context
+exception Unsupported_output_format of string
 
-exception Context of string
+val get_default : unit -> context
+val set_default : context -> unit
+
+val show : ?ctx:context -> Shape.shapes -> unit
+val set_line_width : ?ctx:context -> int -> unit
+
+val writeSVG : ?ctx:context -> string
+val writePNG : ?ctx:context -> string -> unit
 
-val init_context : int * int * int * int -> float -> int * int -> bool -> unit
-val resolution : unit -> int * int
-val set_color : int * int * int -> unit
-val background : int * int * int * int -> unit
-val set_line_width : int -> unit
-val write : context -> string -> unit
-val save : unit -> unit
-val restore : unit -> unit
diff --git a/lib/joy.ml b/lib/joy.ml
index 56ada20..0798b5f 100644
--- a/lib/joy.ml
+++ b/lib/joy.ml
@@ -3,19 +3,29 @@ include Shape
 include Transform
 include Color
 
-let context = Context.context
+module Backend_cairo = Backend_cairo
+module Backend_svg = Backend_svg
+module Backend_lazy = Backend_lazy
+
+type context = Context.context
+let show = Context.show
 let set_line_width = Context.set_line_width
 
-let init ?(background = Color.white) ?(line_width = 2) ?(size = (500, 500))
+(* 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
+    axes *)
+
+let init ?(size = (500, 500)) ?(line_width = 2) ?(axes = false) _ =
+  let ctx = Backend_cairo.create ~background_color:Color.white ~size ~line_width ~axes in
+  let ctx_container = Context.CairoContext ctx in
+  Context.set_default ctx_container;
+  if axes then
+    let half_w, half_h = ctx.size |> Util.tmap float_of_int |> Util.tmap ((/.) 2.) in
+    let x_axis = line ~a:{x = -.half_w; y = 0.} {x = half_w; y = 0.} in
+    let y_axis = line ~a:{x = 0.; y = -.half_h} {x = 0.; y = half_h} in
+    show ~ctx:ctx_container [x_axis; y_axis]
 
 let write ?(filename = "joy.png") () =
-  match !Context.context with
-  | Some ctx ->
-      if ctx.axes then Render.render_axes ();
-      Context.write ctx filename
-  | None -> Context.fail ()
+  Context.writePNG filename
 
-let show shapes = Render.show shapes
diff --git a/lib/joy.mli b/lib/joy.mli
index fee45c5..8f36576 100644
--- a/lib/joy.mli
+++ b/lib/joy.mli
@@ -1,3 +1,8 @@
+module Backend_cairo = Backend_cairo
+module Backend_svg = Backend_svg
+module Backend_lazy = Backend_lazy
+
+type context = Context.context
 type 'a point = 'a Shape.point
 type shape = Shape.shape
 type shapes = Shape.shapes
@@ -11,39 +16,34 @@ val ellipse : ?c:float point -> int -> int -> shape
 val line : ?a:float point -> float point -> shape
 val polygon : float point list -> shape
 val complex : shapes -> shape
-val with_stroke : color -> shape -> shape
-val with_fill : color -> shape -> shape
-val no_stroke : shape -> shape
-val no_fill : shape -> shape
+
 val rotate : int -> transformation
 val translate : int -> int -> transformation
 val scale : float -> transformation
 val compose : transformation -> transformation -> transformation
 val repeat : int -> transformation -> transformation
-val map_stroke : (color -> color) -> shape -> shape
-val map_fill : (color -> color) -> shape -> shape
+
 val random : ?min:int -> int -> int
 val frandom : ?min:float -> float -> float
 val noise : float list -> float
 val fractal_noise : ?octaves:int -> float list -> float
-val context : Context.context option ref
-val set_line_width : int -> unit
+
+val with_stroke : color -> transformation
+val with_fill : color -> transformation
+val map_stroke : (color -> color) -> transformation
+val map_fill : (color -> color) -> transformation
+
 val black : color
 val white : color
 val red : color
 val green : color
 val blue : color
 val yellow : color
-val transparent : int * int * int * int
-val opaque : color -> int * int * int * int
-
-val init :
-  ?background:color ->
-  ?line_width:int ->
-  ?size:int * int ->
-  ?axes:bool ->
-  unit ->
-  unit
-
-val show : shapes -> unit
+val transparent : color
+val rgb : int -> int -> int -> color
+
+val init : ?size:(int * int) -> ?line_width:int -> ?axes:bool -> unit -> unit
 val write : ?filename:string -> unit -> unit
+
+val show : ?ctx:context -> shapes -> unit
+val set_line_width : ?ctx:context -> int -> unit
diff --git a/lib/render.ml b/lib/render.ml
deleted file mode 100644
index 42a7cbc..0000000
--- a/lib/render.ml
+++ /dev/null
@@ -1,89 +0,0 @@
-open Shape
-open Context
-open Util
-
-let draw_circle ctx ({ c; radius; stroke; fill } : circle) =
-  let stroke_circle stroke =
-    set_color stroke;
-    Cairo.stroke_preserve ctx.ctx
-  in
-  let fill_circle fill =
-    set_color fill;
-    Cairo.fill_preserve ctx.ctx
-  in
-  Cairo.arc ctx.ctx c.x (Float.neg c.y) ~r:radius ~a1:0. ~a2:(Float.pi *. 2.);
-  Option.iter stroke_circle stroke;
-  Option.iter fill_circle fill;
-  Cairo.Path.clear ctx.ctx
-
-let draw_ellipse ctx { c; rx; ry; stroke; fill } =
-  let stroke_ellipse stroke =
-    set_color stroke;
-    Cairo.stroke_preserve ctx.ctx
-  in
-  let fill_ellipse fill =
-    set_color fill;
-    Cairo.fill_preserve ctx.ctx
-  in
-
-  (* Save the current transformation matrix *)
-  let save_matrix = Cairo.get_matrix ctx.ctx in
-
-  (* Translate and scale to create an ellipse from a circle *)
-  Cairo.translate ctx.ctx c.x (Float.neg c.y);
-  Cairo.scale ctx.ctx rx ry;
-  Cairo.arc ctx.ctx 0. 0. ~r:1. ~a1:0. ~a2:(2. *. Float.pi);
-
-  (* Restore the original transformation matrix *)
-  Cairo.set_matrix ctx.ctx save_matrix;
-
-  Option.iter stroke_ellipse stroke;
-  Option.iter fill_ellipse fill;
-  Cairo.Path.clear ctx.ctx
-
-let draw_line ctx { a; b; stroke } =
-  set_color stroke;
-  let { x; y } = a in
-  Cairo.move_to ctx.ctx x (Float.neg y);
-  let { x; y } = b in
-  Cairo.line_to ctx.ctx x (Float.neg y);
-  Cairo.stroke ctx.ctx
-
-let draw_polygon ctx { vertices; stroke; fill } =
-  let stroke_rect stroke =
-    set_color stroke;
-    Cairo.stroke_preserve ctx.ctx
-  in
-  let fill_rect fill =
-    set_color fill;
-    Cairo.fill_preserve ctx.ctx
-  in
-  let { x; y }, t = (List.hd vertices, List.tl vertices) in
-  Cairo.move_to ctx.ctx x (Float.neg y);
-  List.iter
-    (fun { x = x'; y = y' } -> Cairo.line_to ctx.ctx x' (Float.neg y'))
-    t;
-  Cairo.Path.close ctx.ctx;
-  Option.iter stroke_rect stroke;
-  Option.iter fill_rect fill;
-  Cairo.Path.clear ctx.ctx
-
-(* Validates context before rendering *)
-let show shapes =
-  let rec render ctx = function
-    | Circle circle -> draw_circle ctx circle
-    | Ellipse ellipse -> draw_ellipse ctx ellipse
-    | Line line -> draw_line ctx line
-    | Polygon polygon -> draw_polygon ctx polygon
-    | Complex complex -> List.iter (render ctx) complex
-  in
-  match !context with
-  | Some ctx -> List.iter (render ctx) shapes
-  | None -> fail ()
-
-let render_axes () =
-  let x, y = resolution () |> tmap float_of_int in
-  let half_x, half_y = (x /. 2., y /. 2.) in
-  let x_axis = line ~a:{ x = 0.; y = -.half_y } { x = 0.; y = half_y } in
-  let y_axis = line ~a:{ x = -.half_x; y = 0. } { x = half_x; y = 0. } in
-  show [ x_axis; y_axis ]
diff --git a/lib/render.mli b/lib/render.mli
deleted file mode 100644
index 87f72dd..0000000
--- a/lib/render.mli
+++ /dev/null
@@ -1,6 +0,0 @@
-val draw_circle : Context.context -> Shape.circle -> unit
-val draw_ellipse : Context.context -> Shape.ellipse -> unit
-val draw_line : Context.context -> Shape.line -> unit
-val draw_polygon : Context.context -> Shape.polygon -> unit
-val render_axes : unit -> unit
-val show : Shape.shape list -> unit
diff --git a/lib/shape.ml b/lib/shape.ml
index d46f947..93a588b 100644
--- a/lib/shape.ml
+++ b/lib/shape.ml
@@ -5,22 +5,22 @@ type line = { a : float point; b : float point; stroke : color }
 type circle = {
   c : float point;
   radius : float;
-  stroke : color option;
-  fill : color option;
+  stroke : color;
+  fill : color;
 }
 
 type ellipse = {
   c : float point;
   rx : float;
   ry : float;
-  stroke : color option;
-  fill : color option;
+  stroke : color;
+  fill : color;
 }
 
 type polygon = {
   vertices : float point list;
-  stroke : color option;
-  fill : color option;
+  stroke : color;
+  fill : color;
 }
 
 type shape =
@@ -36,15 +36,15 @@ let point x y =
   let x, y = (float_of_int x, float_of_int y) in
   { x; y }
 
-let center = { x = 0.; y = 0. }
+let origin = { x = 0.; y = 0. }
 
-let circle ?(c = center) r =
-  Circle { c; radius = float_of_int r; stroke = Some Color.black; fill = None }
+let circle ?(c = origin) r =
+  Circle { c; radius = float_of_int r; stroke = Color.black; fill = Color.transparent }
 
 let polygon vertices =
-  Polygon { vertices; stroke = Some Color.black; fill = None }
+  Polygon { vertices; stroke = Color.black; fill = Color.transparent }
 
-let rectangle ?(c = center) width height =
+let rectangle ?(c = origin) width height =
   let w, h = (float_of_int width, float_of_int height) in
   let x = c.x -. (w /. 2.) in
   let y = c.y -. (h /. 2.) in
@@ -53,45 +53,28 @@ let rectangle ?(c = center) width height =
       { x; y }; { x; y = y +. h }; { x = x +. w; y = y +. h }; { x = x +. w; y };
     ]
 
-let ellipse ?(c = center) rx ry =
+let ellipse ?(c = origin) rx ry =
   let rx, ry = (float_of_int rx, float_of_int ry) in
-  Ellipse { c; rx; ry; stroke = Some Color.black; fill = None }
+  Ellipse { c; rx; ry; stroke = Color.black; fill = Color.transparent }
 
-let line ?(a = center) b = Line { a; b; stroke = Color.black }
+let line ?(a = origin) b = Line { a; b; stroke = Color.black }
 
 let complex shapes =
   match shapes with _ :: _ -> Complex shapes | [] -> Complex []
 
 let rec with_stroke stroke = function
-  | Circle circle' -> Circle { circle' with stroke = Some stroke }
-  | Ellipse ellipse' -> Ellipse { ellipse' with stroke = Some stroke }
+  | Circle circle' -> Circle { circle' with stroke = stroke }
+  | Ellipse ellipse' -> Ellipse { ellipse' with stroke = stroke }
   | Line line' -> Line { line' with stroke }
-  | Polygon polygon' -> Polygon { polygon' with stroke = Some stroke }
+  | Polygon polygon' -> Polygon { polygon' with stroke = stroke }
   | Complex complex' -> Complex (List.map (with_stroke stroke) complex')
 
 let rec with_fill fill = function
-  | Circle circle' -> Circle { circle' with fill = Some fill }
-  | Ellipse ellipse' -> Ellipse { ellipse' with fill = Some fill }
-  | Polygon polygon' -> Polygon { polygon' with fill = Some fill }
+  | Circle circle' -> Circle { circle' with fill }
+  | Ellipse ellipse' -> Ellipse { ellipse' with fill }
+  | Polygon polygon' -> Polygon { polygon' with fill }
   | Complex complex' -> Complex (List.map (with_fill fill) complex')
   | _ as line' ->
       print_endline "lines do not have a fill field!";
       line'
 
-let rec no_stroke = function
-  | Circle circle' -> Circle { circle' with stroke = None }
-  | Ellipse ellipse' -> Ellipse { ellipse' with stroke = None }
-  | Polygon polygon' -> Polygon { polygon' with stroke = None }
-  | Complex complex' -> Complex (List.map no_stroke complex')
-  | _ as line' ->
-      print_endline "Cannot remove stroke from lines";
-      line'
-
-let rec no_fill = function
-  | Circle circle' -> Circle { circle' with fill = None }
-  | Ellipse ellipse' -> Ellipse { ellipse' with fill = None }
-  | Polygon polygon' -> Polygon { polygon' with fill = None }
-  | Complex complex' -> Complex (List.map no_fill complex')
-  | _ as line' ->
-      print_endline "Lines do not have a fill field!";
-      line'
diff --git a/lib/shape.mli b/lib/shape.mli
index 692a488..5f7c113 100644
--- a/lib/shape.mli
+++ b/lib/shape.mli
@@ -4,22 +4,22 @@ type 'a point = { x : 'a; y : 'a }
 type circle = {
   c : float point;
   radius : float;
-  stroke : color option;
-  fill : color option;
+  stroke : color;
+  fill : color;
 }
 
 type ellipse = {
   c : float point;
   rx : float;
   ry : float;
-  stroke : color option;
-  fill : color option;
+  stroke : color;
+  fill : color;
 }
 
 type polygon = {
   vertices : float point list;
-  stroke : color option;
-  fill : color option;
+  stroke : color;
+  fill : color;
 }
 
 type line = { a : float point; b : float point; stroke : color }
@@ -42,5 +42,3 @@ val line : ?a:float point -> float point -> shape
 val polygon : float point list -> shape
 val with_stroke : color -> shape -> shape
 val with_fill : color -> shape -> shape
-val no_stroke : shape -> shape
-val no_fill : shape -> shape
diff --git a/lib/transform.ml b/lib/transform.ml
index b2850ce..9c1e981 100644
--- a/lib/transform.ml
+++ b/lib/transform.ml
@@ -107,20 +107,20 @@ let repeat n op shape =
     function applied to the original's color *)
 let rec map_stroke f = function
   | Circle circle' ->
-      Circle { circle' with stroke = Option.map f circle'.stroke }
+      Circle { circle' with stroke = f circle'.stroke }
   | Ellipse ellipse' ->
-      Ellipse { ellipse' with stroke = Option.map f ellipse'.stroke }
+      Ellipse { ellipse' with stroke = f ellipse'.stroke }
   | Line line' -> Line { line' with stroke = f line'.stroke }
   | Polygon polygon' ->
-      Polygon { polygon' with stroke = Option.map f polygon'.stroke }
+      Polygon { polygon' with stroke = f polygon'.stroke }
   | Complex complex' -> Complex (List.map (map_stroke f) complex')
 
 let rec map_fill f = function
-  | Circle circle' -> Circle { circle' with fill = Option.map f circle'.fill }
+  | Circle circle' -> Circle { circle' with fill = f circle'.fill }
   | Ellipse ellipse' ->
-      Ellipse { ellipse' with fill = Option.map f ellipse'.fill }
+      Ellipse { ellipse' with fill = f ellipse'.fill }
   | Polygon polygon' ->
-      Polygon { polygon' with fill = Option.map f polygon'.fill }
+      Polygon { polygon' with fill = f polygon'.fill }
   | Complex complex' -> Complex (List.map (map_fill f) complex')
   | _ as line' ->
       print_endline "Lines do not have a fill field!";

From 4a67b5653487771abc1d7095e3fdb828c520c306 Mon Sep 17 00:00:00 2001
From: Kaustubh Maske Patil <37668193+nikochiko@users.noreply.github.com>
Date: Tue, 12 Mar 2024 11:09:58 +0530
Subject: [PATCH 2/9] Remove axes from square

---
 examples/square.ml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/examples/square.ml b/examples/square.ml
index 9c68a08..542788c 100644
--- a/examples/square.ml
+++ b/examples/square.ml
@@ -1,7 +1,7 @@
 open Joy
 
 let () =
-  init ~axes:true ();
+  init ();
   let square = rectangle 100 100 in
   show [ square ];
   write ~filename:"square.png" ()

From 9f30f1de0d5dea707cd8399beb1b22ffec081f48 Mon Sep 17 00:00:00 2001
From: Kaustubh Maske Patil <37668193+nikochiko@users.noreply.github.com>
Date: Tue, 12 Mar 2024 11:27:29 +0530
Subject: [PATCH 3/9] Fix bug with rendering axes

---
 examples/dune              |  5 +++++
 examples/line.ml           | 24 ++++++------------------
 examples/parallel_lines.ml | 22 ++++++++++++++++++++++
 lib/color.ml               |  2 ++
 lib/color.mli              |  1 +
 lib/joy.ml                 | 12 ++++--------
 6 files changed, 40 insertions(+), 26 deletions(-)
 create mode 100644 examples/parallel_lines.ml

diff --git a/examples/dune b/examples/dune
index 47a75b9..a88c9b8 100644
--- a/examples/dune
+++ b/examples/dune
@@ -53,6 +53,11 @@
  (modules line)
  (libraries joy))
 
+(executable
+ (name parallel_lines)
+ (modules parallel_lines)
+ (libraries joy))
+
 (executable
  (name higher_transforms)
  (modules higher_transforms)
diff --git a/examples/line.ml b/examples/line.ml
index 2c250c1..d735b8c 100644
--- a/examples/line.ml
+++ b/examples/line.ml
@@ -1,22 +1,10 @@
 open Joy
 
-let size = 800
-let interval = 16
-let line_interval = 800 / interval
-let rec range a b = if a > b then [] else a :: range (a + 1) b
-let inc x = x + 1
-
 let _ =
-  init ~size:(size, size) ();
-  let half_size = size / 2 in
-  let lines =
-    List.map
-      (fun i ->
-        let newx = i |> inc |> ( * ) line_interval in
-        line
-          ~a:(point (newx - half_size) (-half_size))
-          (point (newx - half_size) half_size))
-      (range 0 interval)
-  in
-  show lines;
+  init ();
+  let l1 = line (point 50 50) in
+  let l2 = line (point (-50) 50) in
+  let l3 = line ~a:(point (-50) 50) (point 50 50) in
+  show [l1; l2; l3];
   write ~filename:"line.png" ()
+
diff --git a/examples/parallel_lines.ml b/examples/parallel_lines.ml
new file mode 100644
index 0000000..a557726
--- /dev/null
+++ b/examples/parallel_lines.ml
@@ -0,0 +1,22 @@
+open Joy
+
+let size = 800
+let interval = 16
+let line_interval = 800 / interval
+let rec range a b = if a > b then [] else a :: range (a + 1) b
+let inc x = x + 1
+
+let _ =
+  init ~size:(size, size) ();
+  let half_size = size / 2 in
+  let lines =
+    List.map
+      (fun i ->
+        let newx = i |> inc |> ( * ) line_interval in
+        line
+          ~a:(point (newx - half_size) (-half_size))
+          (point (newx - half_size) half_size))
+      (range 0 interval)
+  in
+  show lines;
+  write ~filename:"parallel_lines.png" ()
diff --git a/lib/color.ml b/lib/color.ml
index 0b5838b..c7121d3 100644
--- a/lib/color.ml
+++ b/lib/color.ml
@@ -7,6 +7,8 @@ let transparent = (0, 0, 0, 0.0)
     For use w/ `Context.background` *)
 let rgb r g b = (r, g, b, 1.0)
 
+let color ?(a = 1.0) r g b = (r, g, b, a)
+
 (** RGB code for black *)
 let black = rgb 0 0 0
 
diff --git a/lib/color.mli b/lib/color.mli
index 0e0496b..3a252dd 100644
--- a/lib/color.mli
+++ b/lib/color.mli
@@ -1,6 +1,7 @@
 type color = int * int * int * float
 
 val rgb : int -> int -> int -> color
+val color : ?a:float -> int -> int -> int -> color
 
 val black : color
 val white : color
diff --git a/lib/joy.ml b/lib/joy.ml
index 0798b5f..9019a0a 100644
--- a/lib/joy.ml
+++ b/lib/joy.ml
@@ -11,19 +11,15 @@ type context = Context.context
 let show = Context.show
 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 *)
-
 let init ?(size = (500, 500)) ?(line_width = 2) ?(axes = false) _ =
   let ctx = Backend_cairo.create ~background_color:Color.white ~size ~line_width ~axes in
   let ctx_container = Context.CairoContext ctx in
   Context.set_default ctx_container;
   if axes then
-    let half_w, half_h = ctx.size |> Util.tmap float_of_int |> Util.tmap ((/.) 2.) in
-    let x_axis = line ~a:{x = -.half_w; y = 0.} {x = half_w; y = 0.} in
-    let y_axis = line ~a:{x = 0.; y = -.half_h} {x = 0.; y = half_h} in
+    let half_w, half_h = ctx.size |> Util.tmap float_of_int |> Util.tmap (fun x -> x /. 2.0) in
+    let gray = Color.color 128 128 128 ~a:0.5 in
+    let x_axis = line ~a:{x = -.half_w; y = 0.} {x = half_w; y = 0.} |> with_stroke gray in
+    let y_axis = line ~a:{x = 0.; y = -.half_h} {x = 0.; y = half_h} |> with_stroke gray in
     show ~ctx:ctx_container [x_axis; y_axis]
 
 let write ?(filename = "joy.png") () =

From 96625350c6d8fc9716f2ee8c2f9597f57bd25616 Mon Sep 17 00:00:00 2001
From: Kaustubh Maske Patil <37668193+nikochiko@users.noreply.github.com>
Date: Tue, 12 Mar 2024 11:32:53 +0530
Subject: [PATCH 4/9] Add comment for axes.ml

---
 examples/axes.ml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/examples/axes.ml b/examples/axes.ml
index c12bbc5..1aee6d5 100644
--- a/examples/axes.ml
+++ b/examples/axes.ml
@@ -2,6 +2,7 @@
 open Joy
 
 let _ =
+  (* intialize rendering context with the axes flag set to true *)
   init ~axes:true ();
   let c = circle 50 in
   show [ c ];

From 137f49e115ad8da00d6afe6f0eda5aeb666700e4 Mon Sep 17 00:00:00 2001
From: Kaustubh Maske Patil <37668193+nikochiko@users.noreply.github.com>
Date: Tue, 12 Mar 2024 11:38:48 +0530
Subject: [PATCH 5/9] Run dune fmt

---
 examples/fill_rect.ml |  1 -
 examples/line.ml      |  3 +--
 lib/backend_cairo.ml  | 35 ++++++++++++++++++-----------------
 lib/backend_cairo.mli | 11 ++++++++---
 lib/backend_lazy.ml   |  1 -
 lib/color.mli         |  1 -
 lib/context.ml        | 37 +++++++++++--------------------------
 lib/context.mli       |  5 +----
 lib/joy.ml            | 26 +++++++++++++++++---------
 lib/joy.mli           |  8 +-------
 lib/shape.ml          | 29 ++++++++++++-----------------
 lib/shape.mli         | 15 ++-------------
 lib/transform.ml      | 33 +++++++++++++++++----------------
 13 files changed, 88 insertions(+), 117 deletions(-)

diff --git a/examples/fill_rect.ml b/examples/fill_rect.ml
index 5ca19b3..bfafecc 100644
--- a/examples/fill_rect.ml
+++ b/examples/fill_rect.ml
@@ -5,4 +5,3 @@ let () =
   let r = rectangle 200 200 |> with_fill (rgb 255 0 0) in
   show [ r ];
   write ~filename:"fill-rect.png" ()
-
diff --git a/examples/line.ml b/examples/line.ml
index d735b8c..68c3798 100644
--- a/examples/line.ml
+++ b/examples/line.ml
@@ -5,6 +5,5 @@ let _ =
   let l1 = line (point 50 50) in
   let l2 = line (point (-50) 50) in
   let l3 = line ~a:(point (-50) 50) (point 50 50) in
-  show [l1; l2; l3];
+  show [ l1; l2; l3 ];
   write ~filename:"line.png" ()
-
diff --git a/lib/backend_cairo.ml b/lib/backend_cairo.ml
index 336feac..38a8f69 100644
--- a/lib/backend_cairo.ml
+++ b/lib/backend_cairo.ml
@@ -2,8 +2,8 @@ type context = {
   cairo_ctx : Cairo.context;
   surface : Cairo.Surface.t;
   size : int * int;
-  background_color: int * int * int * float;
-  axes: bool;
+  background_color : int * int * int * float;
+  axes : bool;
 }
 
 let write ctx filename =
@@ -11,14 +11,14 @@ let write ctx filename =
   Cairo.Surface.finish ctx.surface
 
 let set_color ctx color =
-  let to_float i = (float_of_int i) /. 255. in
+  let to_float i = float_of_int i /. 255. in
   let r, g, b, a = color in
   let r, g, b = Util.tmap3 to_float (r, g, b) in
   Cairo.set_source_rgba ctx.cairo_ctx r g b a
 
 let set_background ctx color =
   let r, g, b, a = color in
-  let to_float i = (float_of_int i) /. 255. in
+  let to_float i = float_of_int i /. 255. in
   let r, g, b = Util.tmap3 to_float (r, g, b) in
   Cairo.set_source_rgba ctx.cairo_ctx r g b a;
   Cairo.paint ctx.cairo_ctx ~alpha:a;
@@ -68,9 +68,7 @@ let draw_polygon ctx vertices stroke fill =
   let x, y = List.hd vertices in
   let t = List.tl vertices in
   Cairo.move_to ctx.cairo_ctx x (Float.neg y);
-  List.iter
-    (fun (x', y') -> Cairo.line_to ctx.cairo_ctx x' (Float.neg y'))
-    t;
+  List.iter (fun (x', y') -> Cairo.line_to ctx.cairo_ctx x' (Float.neg y')) t;
   Cairo.Path.close ctx.cairo_ctx;
   set_color ctx stroke;
   Cairo.stroke_preserve ctx.cairo_ctx;
@@ -79,15 +77,19 @@ let draw_polygon ctx vertices stroke fill =
 
 let show ctx shapes =
   let rec render = function
-    | Shape.Circle circle -> (
-      draw_circle ctx (circle.c.x, circle.c.y) circle.radius circle.stroke circle.fill
-    )
-    | Shape.Ellipse ellipse -> draw_ellipse ctx (ellipse.c.x, ellipse.c.y) ellipse.rx ellipse.ry ellipse.stroke ellipse.fill
-    | Shape.Line line -> draw_line ctx (line.a.x, line.a.y) (line.b.x, line.b.y) line.stroke
-    | Shape.Polygon polygon -> (
-      let to_tuple (point: float Shape.point) = (point.x, point.y) in
-      draw_polygon ctx (List.map to_tuple polygon.vertices) polygon.stroke polygon.fill
-    )
+    | Shape.Circle circle ->
+        draw_circle ctx (circle.c.x, circle.c.y) circle.radius circle.stroke
+          circle.fill
+    | Shape.Ellipse ellipse ->
+        draw_ellipse ctx (ellipse.c.x, ellipse.c.y) ellipse.rx ellipse.ry
+          ellipse.stroke ellipse.fill
+    | Shape.Line line ->
+        draw_line ctx (line.a.x, line.a.y) (line.b.x, line.b.y) line.stroke
+    | Shape.Polygon polygon ->
+        let to_tuple (point : float Shape.point) = (point.x, point.y) in
+        draw_polygon ctx
+          (List.map to_tuple polygon.vertices)
+          polygon.stroke polygon.fill
     | Shape.Complex complex -> List.iter render complex
   in
   List.iter render shapes
@@ -101,4 +103,3 @@ let create ~background_color ~line_width ~size ~axes =
   set_background ctx background_color;
   set_line_width ctx line_width;
   ctx
-
diff --git a/lib/backend_cairo.mli b/lib/backend_cairo.mli
index 3a67e8f..b6b23e5 100644
--- a/lib/backend_cairo.mli
+++ b/lib/backend_cairo.mli
@@ -2,8 +2,8 @@ type context = {
   cairo_ctx : Cairo.context;
   surface : Cairo.Surface.t;
   size : int * int;
-  background_color: Color.color;
-  axes: bool;
+  background_color : Color.color;
+  axes : bool;
 }
 
 val set_color : context -> Color.color -> unit
@@ -12,4 +12,9 @@ val set_line_width : context -> int -> unit
 val show : context -> Shape.shapes -> unit
 val write : context -> string -> unit
 
-val create : background_color:Color.color -> line_width:int -> size:int * int -> axes:bool -> context
+val create :
+  background_color:Color.color ->
+  line_width:int ->
+  size:int * int ->
+  axes:bool ->
+  context
diff --git a/lib/backend_lazy.ml b/lib/backend_lazy.ml
index e2d719e..e0c304c 100644
--- a/lib/backend_lazy.ml
+++ b/lib/backend_lazy.ml
@@ -2,4 +2,3 @@ type context = unit
 
 let show _ctx _shapes = ()
 let create _ = ()
-
diff --git a/lib/color.mli b/lib/color.mli
index 3a252dd..8984bac 100644
--- a/lib/color.mli
+++ b/lib/color.mli
@@ -2,7 +2,6 @@ type color = int * int * int * float
 
 val rgb : int -> int -> int -> color
 val color : ?a:float -> int -> int -> int -> color
-
 val black : color
 val white : color
 val red : color
diff --git a/lib/context.ml b/lib/context.ml
index 6fcc83d..876a3db 100644
--- a/lib/context.ml
+++ b/lib/context.ml
@@ -1,5 +1,5 @@
 type context =
-    CairoContext of Backend_cairo.context
+  | CairoContext of Backend_cairo.context
   | SVGContext of Backend_svg.context
   | LazyContext of Backend_lazy.context
 
@@ -7,50 +7,35 @@ exception No_context
 exception Unsupported_output_format of string
 
 let default = ref (LazyContext (Backend_lazy.create ()))
-
-let get_default _ =
-  !default
-
-let set_default ctx =
-  default := ctx
+let get_default _ = !default
+let set_default ctx = default := ctx
 
 let show ?ctx shapes =
-  let ctx = match ctx with
-    | Some ctx -> ctx
-    | None -> get_default ()
-  in
+  let ctx = match ctx with Some ctx -> ctx | None -> get_default () in
   match ctx with
   | CairoContext ctx -> Backend_cairo.show ctx shapes
   | SVGContext ctx -> Backend_svg.show ctx shapes
   | LazyContext ctx -> Backend_lazy.show ctx shapes
 
 let set_line_width ?ctx int =
-  let ctx = match ctx with
-  | Some ctx -> ctx
-  | None -> get_default ()
-  in
+  let ctx = match ctx with Some ctx -> ctx | None -> get_default () in
   match ctx with
   | CairoContext ctx -> Backend_cairo.set_line_width ctx int
   | SVGContext _ -> failwith "SVG.set_line_width ctx int"
   | LazyContext _ -> failwith "Backend_lazy.set_line_width ctx int"
 
 let writePNG ?ctx filename =
-  let ctx = match ctx with
-    | Some ctx -> ctx
-    | None -> get_default ()
-  in
+  let ctx = match ctx with Some ctx -> ctx | None -> get_default () in
   match ctx with
   | CairoContext ctx -> Backend_cairo.write ctx filename
-  | SVGContext _ -> raise (Unsupported_output_format "SVG context cannot render to PNG")
+  | SVGContext _ ->
+      raise (Unsupported_output_format "SVG context cannot render to PNG")
   | LazyContext _ -> failwith "Lazy.writePNG ctx filename"
 
 let writeSVG ?ctx =
-  let ctx = match ctx with
-    | Some ctx -> ctx
-    | None -> get_default ()
-  in
+  let ctx = match ctx with Some ctx -> ctx | None -> get_default () in
   match ctx with
-  | CairoContext _ -> raise (Unsupported_output_format "Cairo context cannot render to SVG")
+  | CairoContext _ ->
+      raise (Unsupported_output_format "Cairo context cannot render to SVG")
   | SVGContext _ -> failwith "SVG.writeSVG ctx"
   | LazyContext _ -> failwith "Lazy.writeSVG ctx"
-
diff --git a/lib/context.mli b/lib/context.mli
index 01b57ec..d789c84 100644
--- a/lib/context.mli
+++ b/lib/context.mli
@@ -1,5 +1,5 @@
 type context =
-    CairoContext of Backend_cairo.context
+  | CairoContext of Backend_cairo.context
   | SVGContext of Backend_svg.context
   | LazyContext of Backend_lazy.context
 
@@ -8,10 +8,7 @@ exception Unsupported_output_format of string
 
 val get_default : unit -> context
 val set_default : context -> unit
-
 val show : ?ctx:context -> Shape.shapes -> unit
 val set_line_width : ?ctx:context -> int -> unit
-
 val writeSVG : ?ctx:context -> string
 val writePNG : ?ctx:context -> string -> unit
-
diff --git a/lib/joy.ml b/lib/joy.ml
index 9019a0a..bc163c8 100644
--- a/lib/joy.ml
+++ b/lib/joy.ml
@@ -2,26 +2,34 @@ include Random
 include Shape
 include Transform
 include Color
-
 module Backend_cairo = Backend_cairo
 module Backend_svg = Backend_svg
 module Backend_lazy = Backend_lazy
 
 type context = Context.context
+
 let show = Context.show
 let set_line_width = Context.set_line_width
 
 let init ?(size = (500, 500)) ?(line_width = 2) ?(axes = false) _ =
-  let ctx = Backend_cairo.create ~background_color:Color.white ~size ~line_width ~axes in
+  let ctx =
+    Backend_cairo.create ~background_color:Color.white ~size ~line_width ~axes
+  in
   let ctx_container = Context.CairoContext ctx in
   Context.set_default ctx_container;
   if axes then
-    let half_w, half_h = ctx.size |> Util.tmap float_of_int |> Util.tmap (fun x -> x /. 2.0) in
+    let half_w, half_h =
+      ctx.size |> Util.tmap float_of_int |> Util.tmap (fun x -> x /. 2.0)
+    in
     let gray = Color.color 128 128 128 ~a:0.5 in
-    let x_axis = line ~a:{x = -.half_w; y = 0.} {x = half_w; y = 0.} |> with_stroke gray in
-    let y_axis = line ~a:{x = 0.; y = -.half_h} {x = 0.; y = half_h} |> with_stroke gray in
-    show ~ctx:ctx_container [x_axis; y_axis]
-
-let write ?(filename = "joy.png") () =
-  Context.writePNG filename
+    let x_axis =
+      line ~a:{ x = -.half_w; y = 0. } { x = half_w; y = 0. }
+      |> with_stroke gray
+    in
+    let y_axis =
+      line ~a:{ x = 0.; y = -.half_h } { x = 0.; y = half_h }
+      |> with_stroke gray
+    in
+    show ~ctx:ctx_container [ x_axis; y_axis ]
 
+let write ?(filename = "joy.png") () = Context.writePNG filename
diff --git a/lib/joy.mli b/lib/joy.mli
index 8f36576..1b7be45 100644
--- a/lib/joy.mli
+++ b/lib/joy.mli
@@ -16,23 +16,19 @@ val ellipse : ?c:float point -> int -> int -> shape
 val line : ?a:float point -> float point -> shape
 val polygon : float point list -> shape
 val complex : shapes -> shape
-
 val rotate : int -> transformation
 val translate : int -> int -> transformation
 val scale : float -> transformation
 val compose : transformation -> transformation -> transformation
 val repeat : int -> transformation -> transformation
-
 val random : ?min:int -> int -> int
 val frandom : ?min:float -> float -> float
 val noise : float list -> float
 val fractal_noise : ?octaves:int -> float list -> float
-
 val with_stroke : color -> transformation
 val with_fill : color -> transformation
 val map_stroke : (color -> color) -> transformation
 val map_fill : (color -> color) -> transformation
-
 val black : color
 val white : color
 val red : color
@@ -41,9 +37,7 @@ val blue : color
 val yellow : color
 val transparent : color
 val rgb : int -> int -> int -> color
-
-val init : ?size:(int * int) -> ?line_width:int -> ?axes:bool -> unit -> unit
+val init : ?size:int * int -> ?line_width:int -> ?axes:bool -> unit -> unit
 val write : ?filename:string -> unit -> unit
-
 val show : ?ctx:context -> shapes -> unit
 val set_line_width : ?ctx:context -> int -> unit
diff --git a/lib/shape.ml b/lib/shape.ml
index 93a588b..c804238 100644
--- a/lib/shape.ml
+++ b/lib/shape.ml
@@ -1,13 +1,7 @@
 type 'a point = { x : 'a; y : 'a }
 type color = Color.color
 type line = { a : float point; b : float point; stroke : color }
-
-type circle = {
-  c : float point;
-  radius : float;
-  stroke : color;
-  fill : color;
-}
+type circle = { c : float point; radius : float; stroke : color; fill : color }
 
 type ellipse = {
   c : float point;
@@ -17,11 +11,7 @@ type ellipse = {
   fill : color;
 }
 
-type polygon = {
-  vertices : float point list;
-  stroke : color;
-  fill : color;
-}
+type polygon = { vertices : float point list; stroke : color; fill : color }
 
 type shape =
   | Circle of circle
@@ -39,7 +29,13 @@ let point x y =
 let origin = { x = 0.; y = 0. }
 
 let circle ?(c = origin) r =
-  Circle { c; radius = float_of_int r; stroke = Color.black; fill = Color.transparent }
+  Circle
+    {
+      c;
+      radius = float_of_int r;
+      stroke = Color.black;
+      fill = Color.transparent;
+    }
 
 let polygon vertices =
   Polygon { vertices; stroke = Color.black; fill = Color.transparent }
@@ -63,10 +59,10 @@ let complex shapes =
   match shapes with _ :: _ -> Complex shapes | [] -> Complex []
 
 let rec with_stroke stroke = function
-  | Circle circle' -> Circle { circle' with stroke = stroke }
-  | Ellipse ellipse' -> Ellipse { ellipse' with stroke = stroke }
+  | Circle circle' -> Circle { circle' with stroke }
+  | Ellipse ellipse' -> Ellipse { ellipse' with stroke }
   | Line line' -> Line { line' with stroke }
-  | Polygon polygon' -> Polygon { polygon' with stroke = stroke }
+  | Polygon polygon' -> Polygon { polygon' with stroke }
   | Complex complex' -> Complex (List.map (with_stroke stroke) complex')
 
 let rec with_fill fill = function
@@ -77,4 +73,3 @@ let rec with_fill fill = function
   | _ as line' ->
       print_endline "lines do not have a fill field!";
       line'
-
diff --git a/lib/shape.mli b/lib/shape.mli
index 5f7c113..d0a01a5 100644
--- a/lib/shape.mli
+++ b/lib/shape.mli
@@ -1,12 +1,6 @@
 type color = Color.color
 type 'a point = { x : 'a; y : 'a }
-
-type circle = {
-  c : float point;
-  radius : float;
-  stroke : color;
-  fill : color;
-}
+type circle = { c : float point; radius : float; stroke : color; fill : color }
 
 type ellipse = {
   c : float point;
@@ -16,12 +10,7 @@ type ellipse = {
   fill : color;
 }
 
-type polygon = {
-  vertices : float point list;
-  stroke : color;
-  fill : color;
-}
-
+type polygon = { vertices : float point list; stroke : color; fill : color }
 type line = { a : float point; b : float point; stroke : color }
 
 type shape =
diff --git a/lib/transform.ml b/lib/transform.ml
index 9c1e981..fa71aa2 100644
--- a/lib/transform.ml
+++ b/lib/transform.ml
@@ -50,11 +50,11 @@ let rec scale factor = function
         }
   | Line line' ->
       Line
-      {
-        line' with
-        a = Util.pmap (scale_length factor) line'.a;
-        b = Util.pmap (scale_length factor) line'.b;
-      }
+        {
+          line' with
+          a = Util.pmap (scale_length factor) line'.a;
+          b = Util.pmap (scale_length factor) line'.b;
+        }
   | Polygon polygon' ->
       Polygon
         {
@@ -83,7 +83,13 @@ let rec rotate degrees = function
   | Circle circle' -> Circle { circle' with c = rotate_point degrees circle'.c }
   | Ellipse ellipse' ->
       Ellipse { ellipse' with c = rotate_point degrees ellipse'.c }
-  | Line line' -> Line { line' with a = rotate_point degrees line'.a; b = rotate_point degrees line'.b }
+  | Line line' ->
+      Line
+        {
+          line' with
+          a = rotate_point degrees line'.a;
+          b = rotate_point degrees line'.b;
+        }
   | Polygon polygon' ->
       Polygon
         {
@@ -106,21 +112,16 @@ let repeat n op shape =
 (** Takes a function and a shape and returns a new shape with the 
     function applied to the original's color *)
 let rec map_stroke f = function
-  | Circle circle' ->
-      Circle { circle' with stroke = f circle'.stroke }
-  | Ellipse ellipse' ->
-      Ellipse { ellipse' with stroke = f ellipse'.stroke }
+  | Circle circle' -> Circle { circle' with stroke = f circle'.stroke }
+  | Ellipse ellipse' -> Ellipse { ellipse' with stroke = f ellipse'.stroke }
   | Line line' -> Line { line' with stroke = f line'.stroke }
-  | Polygon polygon' ->
-      Polygon { polygon' with stroke = f polygon'.stroke }
+  | Polygon polygon' -> Polygon { polygon' with stroke = f polygon'.stroke }
   | Complex complex' -> Complex (List.map (map_stroke f) complex')
 
 let rec map_fill f = function
   | Circle circle' -> Circle { circle' with fill = f circle'.fill }
-  | Ellipse ellipse' ->
-      Ellipse { ellipse' with fill = f ellipse'.fill }
-  | Polygon polygon' ->
-      Polygon { polygon' with fill = f polygon'.fill }
+  | Ellipse ellipse' -> Ellipse { ellipse' with fill = f ellipse'.fill }
+  | Polygon polygon' -> Polygon { polygon' with fill = f polygon'.fill }
   | Complex complex' -> Complex (List.map (map_fill f) complex')
   | _ as line' ->
       print_endline "Lines do not have a fill field!";

From 292e9d65919108b09a561a39724fa9030ee2959e Mon Sep 17 00:00:00 2001
From: Kaustubh Maske Patil <37668193+nikochiko@users.noreply.github.com>
Date: Tue, 12 Mar 2024 11:41:51 +0530
Subject: [PATCH 6/9] Default line_width to 1 for cairo

---
 lib/backend_cairo.ml | 3 +--
 lib/joy.ml           | 2 +-
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/lib/backend_cairo.ml b/lib/backend_cairo.ml
index 38a8f69..aea5c3e 100644
--- a/lib/backend_cairo.ml
+++ b/lib/backend_cairo.ml
@@ -25,8 +25,7 @@ let set_background ctx color =
   Cairo.fill ctx.cairo_ctx
 
 (** Sets the width of lines for both stroke of shapes and line primitives. 
-    Can be any positive integer, with larger numbers producing thicker lines. 
-    default is 2 *)
+    Can be any positive integer, with larger numbers producing thicker lines. *)
 let set_line_width ctx line_width =
   Cairo.set_line_width ctx.cairo_ctx (float_of_int line_width)
 
diff --git a/lib/joy.ml b/lib/joy.ml
index bc163c8..d8c19eb 100644
--- a/lib/joy.ml
+++ b/lib/joy.ml
@@ -11,7 +11,7 @@ type context = Context.context
 let show = Context.show
 let set_line_width = Context.set_line_width
 
-let init ?(size = (500, 500)) ?(line_width = 2) ?(axes = false) _ =
+let init ?(size = (500, 500)) ?(line_width = 1) ?(axes = false) _ =
   let ctx =
     Backend_cairo.create ~background_color:Color.white ~size ~line_width ~axes
   in

From 0caf3fab43d4c40ecd26df213b76511bf5a476d1 Mon Sep 17 00:00:00 2001
From: Kaustubh Maske Patil <37668193+nikochiko@users.noreply.github.com>
Date: Tue, 12 Mar 2024 11:51:06 +0530
Subject: [PATCH 7/9] Remove stale comment for backend_cairo.ml

---
 lib/backend_cairo.ml | 1 -
 1 file changed, 1 deletion(-)

diff --git a/lib/backend_cairo.ml b/lib/backend_cairo.ml
index aea5c3e..f592f3b 100644
--- a/lib/backend_cairo.ml
+++ b/lib/backend_cairo.ml
@@ -30,7 +30,6 @@ let set_line_width ctx line_width =
   Cairo.set_line_width ctx.cairo_ctx (float_of_int line_width)
 
 let draw_circle ctx (cx, cy) radius stroke fill =
-  (* TODO: stroke and fill MUST have a value before coming to the renderer *)
   Cairo.arc ctx.cairo_ctx cx (Float.neg cy) ~r:radius ~a1:0. ~a2:(Float.pi *. 2.);
   set_color ctx stroke;
   Cairo.stroke_preserve ctx.cairo_ctx;

From c01733002e6d9de18ee208b72ba250a89be99606 Mon Sep 17 00:00:00 2001
From: Kaustubh Maske Patil <37668193+nikochiko@users.noreply.github.com>
Date: Tue, 12 Mar 2024 12:11:48 +0530
Subject: [PATCH 8/9] Run dune fmt

---
 examples/smile.ml | 41 ++++++++++++++++++++---------------------
 lib/shape.ml      |  3 ++-
 2 files changed, 22 insertions(+), 22 deletions(-)

diff --git a/examples/smile.ml b/examples/smile.ml
index 89ca1d3..85f2842 100644
--- a/examples/smile.ml
+++ b/examples/smile.ml
@@ -1,27 +1,26 @@
 open Joy
 
 let make_nose () =
-    let l = line (point 0 50)|> translate 0 (-25) in
-    let l1 = l in
-    let l2 = l |> rotate 90|> translate 0 (-25) in
-    let nose = complex [l1; l2] in
-    nose
+  let l = line (point 0 50) |> translate 0 (-25) in
+  let l1 = l in
+  let l2 = l |> rotate 90 |> translate 0 (-25) in
+  let nose = complex [ l1; l2 ] in
+  nose
 
-let make_arc rx ry = 
-    let r = rectangle ~c:(point 0 (ry / 2)) (2 * rx) ry in 
-    let col = r |> with_fill white |> with_stroke white in
-    let e = ellipse ~c:(point 0 0) rx ry in
-    complex [e; col]
+let make_arc rx ry =
+  let r = rectangle ~c:(point 0 (ry / 2)) (2 * rx) ry in
+  let col = r |> with_fill white |> with_stroke white in
+  let e = ellipse ~c:(point 0 0) rx ry in
+  complex [ e; col ]
 
 let () =
-    init ();
-    let a = circle 200 in
-    let d = circle ~c:(point 50 50) 20 in
-    let b = circle ~c:(point (-50) 50) 20 in
-    let nose = make_nose () in
-    let leb = make_arc 26 14 |> rotate 180 |> translate 50 70  in
-    let reb = make_arc 26 14 |> rotate 180 |> translate (-50) 70  in 
-    let mouth = make_arc 80 40 |>translate 0 (-60) in 
-    show [mouth;leb;reb;a;d;b;nose];
-    write ()
-
+  init ();
+  let a = circle 200 in
+  let d = circle ~c:(point 50 50) 20 in
+  let b = circle ~c:(point (-50) 50) 20 in
+  let nose = make_nose () in
+  let leb = make_arc 26 14 |> rotate 180 |> translate 50 70 in
+  let reb = make_arc 26 14 |> rotate 180 |> translate (-50) 70 in
+  let mouth = make_arc 80 40 |> translate 0 (-60) in
+  show [ mouth; leb; reb; a; d; b; nose ];
+  write ()
diff --git a/lib/shape.ml b/lib/shape.ml
index 50451b5..7c6fc3e 100644
--- a/lib/shape.ml
+++ b/lib/shape.ml
@@ -52,7 +52,8 @@ let rectangle ?(c = origin) width height =
 
 let ellipse ?(c = origin) rx ry =
   let rx, ry = (float_of_int rx, float_of_int ry) in
-  Ellipse { c; rx; ry; stroke = Color.black; fill = Color.transparent; rotation = 0. }
+  Ellipse
+    { c; rx; ry; stroke = Color.black; fill = Color.transparent; rotation = 0. }
 
 let line ?(a = origin) b = Line { a; b; stroke = Color.black }
 

From 069d525a16e384196fccb1a0edc6c2148761b891 Mon Sep 17 00:00:00 2001
From: Kaustubh Maske Patil <37668193+nikochiko@users.noreply.github.com>
Date: Tue, 12 Mar 2024 12:12:44 +0530
Subject: [PATCH 9/9] Re-add base to joy.opam

---
 joy.opam | 1 +
 1 file changed, 1 insertion(+)

diff --git a/joy.opam b/joy.opam
index c5bfbd8..632ce28 100644
--- a/joy.opam
+++ b/joy.opam
@@ -12,6 +12,7 @@ depends: [
   "dune" {>= "3.10"}
   "graphics"
   "cairo2"
+  "base"
   "odoc" {with-doc}
 ]
 build: [