turn off debugging printfs

src/pathops/SkPathOpsCubic.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #include "SkLineParameters.h"
 #include "SkPathOpsCubic.h"
 #include "SkPathOpsLine.h"
 #include "SkPathOpsQuad.h"
@@ skipping 286 matching lines @@
     SkDCubic sub = subDivide(startT, endT);
     SkDPoint topPt = sub[0];
     if (topPt.fY > sub[3].fY || (topPt.fY == sub[3].fY && topPt.fX > sub[3].fX)) {
         topPt = sub[3];
     }
     double extremeTs[2];
     if (!sub.monotonicInY()) {
         int roots = FindExtrema(sub[0].fY, sub[1].fY, sub[2].fY, sub[3].fY, extremeTs);
         for (int index = 0; index < roots; ++index) {
             double t = startT + (endT - startT) * extremeTs[index];
-            SkDPoint mid = xyAtT(t);
+            SkDPoint mid = ptAtT(t);
             if (topPt.fY > mid.fY || (topPt.fY == mid.fY && topPt.fX > mid.fX)) {
                 topPt = mid;
             }
         }
     }
     return topPt;
 }
 
-SkDPoint SkDCubic::xyAtT(double t) const {
+SkDPoint SkDCubic::ptAtT(double t) const {
+    if (0 == t) {
+        return fPts[0];
+    }
+    if (1 == t) {
+        return fPts[3];
+    }
     double one_t = 1 - t;
     double one_t2 = one_t * one_t;
     double a = one_t2 * one_t;
     double b = 3 * one_t2 * t;
     double t2 = t * t;
     double c = 3 * one_t * t2;
     double d = t2 * t;
     SkDPoint result = {a * fPts[0].fX + b * fPts[1].fX + c * fPts[2].fX + d * fPts[3].fX,
             a * fPts[0].fY + b * fPts[1].fY + c * fPts[2].fY + d * fPts[3].fY};
     return result;
@@ skipping 168 matching lines @@
         dst.pts[4].fY = (fPts[1].fY + 2 * fPts[2].fY + fPts[3].fY) / 4;
         dst.pts[5].fX = (fPts[2].fX + fPts[3].fX) / 2;
         dst.pts[5].fY = (fPts[2].fY + fPts[3].fY) / 2;
         dst.pts[6] = fPts[3];
         return dst;
     }
     interp_cubic_coords(&fPts[0].fX, &dst.pts[0].fX, t);
     interp_cubic_coords(&fPts[0].fY, &dst.pts[0].fY, t);
     return dst;
 }