Minor code cleanup

lib/a2c.js

@@ -1,14 +1,11 @@
 // Convert an arc to a sequence of cubic bézier curves
 //
-
 'use strict';
 
+
 var TAU = Math.PI * 2;
 
-// causes an error in case of a long url in comments
-/* eslint-disable max-len */
 
-// spaces are used for grouping throughout this file
 /* eslint-disable space-infix-ops */
 
 // Calculate an angle between two vectors
@@ -20,30 +17,13 @@ function vector_angle(ux, uy, vx, vy) {
   var dot  = ux * vx + uy * vy;
   var div  = dot / (umag * vmag);
 
-  if (div > 1 || div < -1) {
-    // rounding errors, e.g. -1.0000000000000002 can screw up this
-    div = Math.max(div, -1);
-    div = Math.min(div,  1);
-  }
+  // rounding errors, e.g. -1.0000000000000002 can screw up this
+  if (div >  1.0) { div =  1.0; }
+  if (div < -1.0) { div = -1.0; }
 
   return sign * Math.acos(div);
 }
 
-// Correction of out-of-range radii
-//
-function correct_radii(midx, midy, rx, ry) {
-  rx = Math.abs(rx);
-  ry = Math.abs(ry);
-
-  var Λ = (midx * midx) / (rx * rx) + (midy * midy) / (ry * ry);
-  if (Λ > 1) {
-    rx *= Math.sqrt(Λ);
-    ry *= Math.sqrt(Λ);
-  }
-
-  return [ rx, ry ];
-}
-
 
 // Convert from endpoint to center parameterization,
 // see http://www.w3.org/TR/SVG11/implnote.html#ArcImplementationNotes
@@ -115,7 +95,7 @@ function get_arc_center(x1, y1, x2, y2, fa, fs, rx, ry, sin_φ, cos_φ) {
 
 //
 // Approximate one unit arc segment with bézier curves,
-// see http://math.stackexchange.com/questions/873224/calculate-control-points-of-cubic-bezier-curve-approximating-a-part-of-a-circle
+// see http://math.stackexchange.com/questions/873224
 //
 function approximate_unit_arc(θ1, Δθ) {
   var α = 4/3 * Math.tan(Δθ/4);
@@ -147,9 +127,18 @@ module.exports = function a2c(x1, y1, x2, y2, fa, fs, rx, ry, φ) {
     return [];
   }
 
-  var radii = correct_radii(x1p, y1p, rx, ry);
-  rx = radii[0];
-  ry = radii[1];
+
+  // Compensate out-of-range radii
+  //
+  rx = Math.abs(rx);
+  ry = Math.abs(ry);
+
+  var Λ = (x1p * x1p) / (rx * rx) + (y1p * y1p) / (ry * ry);
+  if (Λ > 1) {
+    rx *= Math.sqrt(Λ);
+    ry *= Math.sqrt(Λ);
+  }
+
 
   // Get center parameters (cx, cy, θ1, Δθ)
   //