xref: /aosp_15_r20/external/skia/docs/examples/Path_IsCubicDegenerate.cpp (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1 // Copyright 2019 Google LLC.
2 // Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
3 #include "tools/fiddle/examples.h"
4 REG_FIDDLE(Path_IsCubicDegenerate, 256, 256, true, 0) {
draw(SkCanvas * canvas)5 void draw(SkCanvas* canvas) {
6     SkPoint points[] = {{1, 0}, {0, 0}, {0, 0}, {0, 0}};
7     SkScalar step = 1;
8     SkScalar prior, length = 0, degenerate = 0;
9     do {
10         prior = points[0].fX;
11         step /= 2;
12         if (SkPath::IsCubicDegenerate(points[0], points[1], points[2], points[3], false)) {
13             degenerate = prior;
14             points[0].fX += step;
15         } else {
16             length = prior;
17             points[0].fX -= step;
18         }
19     } while (prior != points[0].fX);
20     SkDebugf("%1.8g is degenerate\n", degenerate);
21     SkDebugf("%1.8g is length\n", length);
22 }
23 }  // END FIDDLE
24