1 files changed, 23 insertions, 0 deletions
diff --git a/src/arc.ml b/src/arc.ml
new file mode 100644
index 0000000..7a3195d
--- /dev/null
+++ b/src/arc.ml
@@ -0,0 +1,23 @@
+let polarToCartesian centerX centerY radius angleInDegrees =
+  let angleInRadians = (angleInDegrees -. 90.0) *. Js.Math._PI /. 180.0 in
+  ( centerX +. (radius *. Js.Math.cos angleInRadians),
+    centerY +. (radius *. Js.Math.sin angleInRadians) )
+
+let describe x y radius startAngle endAngle =
+  let startX, startY = polarToCartesian x y radius endAngle in
+  let endX, endY = polarToCartesian x y radius startAngle in
+  let largeArcFlag = if endAngle -. startAngle <= 180.0 then "0" else "1" in
+  [|
+    "M";
+    Js.Float.toString startX;
+    Js.Float.toString startY;
+    "A";
+    Js.Float.toString radius;
+    Js.Float.toString radius;
+    "0";
+    largeArcFlag;
+    "0";
+    Js.Float.toString endX;
+    Js.Float.toString endY;
+  |]
+  |> Js.Array.joinWith " "