simplify loop

Author: mbostock

docs/ex/d3/orthographic-to-equirectangular.html

@@ -32,28 +32,26 @@
     const path = d3.geoPath(projection, context);
 
     const animation = (function* () {
-      while (true) {
-        for (let i = 0, n = 480; i < n; ++i) {
-          const t = d3.easeCubic(2 * i > n ? 2 - 2 * i / n : 2 * i / n);
-          projection.alpha(t).rotate(rotate(t)).scale(scale(t));
-          context.clearRect(0, 0, width, height);
-          context.beginPath();
-          path(graticule);
-          context.lineWidth = 1;
-          context.strokeStyle = "#aaa";
-          context.stroke();
-          context.beginPath();
-          path(sphere);
-          context.lineWidth = 1.5;
-          context.strokeStyle = "#000";
-          context.stroke();
-          context.beginPath();
-          path(equator);
-          context.lineWidth = 1.5;
-          context.strokeStyle = "#f00";
-          context.stroke();
-          yield context.canvas;
-        }
+      for (let i = 0, n = 480; true; i = (i + 1) % n) {
+        const t = d3.easeCubic(2 * i > n ? 2 - 2 * i / n : 2 * i / n);
+        projection.alpha(t).rotate(rotate(t)).scale(scale(t));
+        context.clearRect(0, 0, width, height);
+        context.beginPath();
+        path(graticule);
+        context.lineWidth = 1;
+        context.strokeStyle = "#aaa";
+        context.stroke();
+        context.beginPath();
+        path(sphere);
+        context.lineWidth = 1.5;
+        context.strokeStyle = "#000";
+        context.stroke();
+        context.beginPath();
+        path(equator);
+        context.lineWidth = 1.5;
+        context.strokeStyle = "#f00";
+        context.stroke();
+        yield context.canvas;
       }
     })();