SkCanvas interface for drawing a patch.

src/core/SkGeometry.cpp

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkGeometry.h"
 #include "SkMatrix.h"
 
@@ skipping 986 matching lines @@
         if (SkXRayCrossesMonotonicCubic(pt,
                                         &monotonic_cubics[6],
                                         &locally_ambiguous))
             ++num_crossings;
     if (ambiguous) {
         *ambiguous |= locally_ambiguous;
     }
     return num_crossings;
 }
 
+/**
+ * Calculate the approximate arc length given a bezier curve's control points.
+ */
+SkScalar approx_arc_length(SkPoint* points, int count) {
+    if (count < 2) {
+        return 0;
+    }
+    SkScalar arcLength = 0;
+    for (int i = 0; i < count - 1; i++) {
+        arcLength += SkPoint::Distance(points[i], points[i + 1]);
+    }
+    return arcLength;
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 
 /*  Find t value for quadratic [a, b, c] = d.
     Return 0 if there is no solution within [0, 1)
 */
 static SkScalar quad_solve(SkScalar a, SkScalar b, SkScalar c, SkScalar d) {
     // At^2 + Bt + C = d
     SkScalar A = a - 2 * b + c;
     SkScalar B = 2 * (b - a);
     SkScalar C = a - d;
@@ skipping 442 matching lines @@
 }
 
 void SkConic::computeFastBounds(SkRect* bounds) const {
     bounds->set(fPts, 3);
 }
 
 bool SkConic::findMaxCurvature(SkScalar* t) const {
     // TODO: Implement me
     return false;
 }