use conics for arcTo

tests/PathTest.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkCanvas.h"
 #include "SkPaint.h"
 #include "SkParse.h"
@@ skipping 3212 matching lines @@
 }
 
 static void check_path_is_quad_and_reset(skiatest::Reporter* reporter, SkPath* p,
                                     SkScalar x1, SkScalar y1, SkScalar x2, SkScalar y2) {
     SkPath::RawIter iter(*p);
     check_move(reporter, &iter, 0, 0);
     check_quad(reporter, &iter, x1, y1, x2, y2);
     check_done_and_reset(reporter, p, &iter);
 }
 
+static bool nearly_equal(const SkRect& a, const SkRect& b) {
+    return  SkScalarNearlyEqual(a.fLeft, b.fLeft) &&
+            SkScalarNearlyEqual(a.fTop, b.fTop) &&
+            SkScalarNearlyEqual(a.fRight, b.fRight) &&
+            SkScalarNearlyEqual(a.fBottom, b.fBottom);
+}
+
 static void test_arcTo(skiatest::Reporter* reporter) {
     SkPath p;
     p.arcTo(0, 0, 1, 2, 1);
     check_path_is_line_and_reset(reporter, &p, 0, 0);
     p.arcTo(1, 2, 1, 2, 1);
     check_path_is_line_and_reset(reporter, &p, 1, 2);
     p.arcTo(1, 2, 3, 4, 0);
     check_path_is_line_and_reset(reporter, &p, 1, 2);
     p.arcTo(1, 2, 0, 0, 1);
     check_path_is_line_and_reset(reporter, &p, 1, 2);
     p.arcTo(1, 0, 1, 1, 1);
     SkPoint pt;
     REPORTER_ASSERT(reporter, p.getLastPt(&pt) && pt.fX == 1 && pt.fY == 1);
     p.reset();
     p.arcTo(1, 0, 1, -1, 1);
     REPORTER_ASSERT(reporter, p.getLastPt(&pt) && pt.fX == 1 && pt.fY == -1);
     p.reset();
     SkRect oval = {1, 2, 3, 4};
     p.arcTo(oval, 0, 0, true);
     check_path_is_move_and_reset(reporter, &p, oval.fRight, oval.centerY());
     p.arcTo(oval, 0, 0, false);
     check_path_is_move_and_reset(reporter, &p, oval.fRight, oval.centerY());
     p.arcTo(oval, 360, 0, true);
     check_path_is_move_and_reset(reporter, &p, oval.fRight, oval.centerY());
     p.arcTo(oval, 360, 0, false);
     check_path_is_move_and_reset(reporter, &p, oval.fRight, oval.centerY());
+
     for (float sweep = 359, delta = 0.5f; sweep != (float) (sweep + delta); ) {
         p.arcTo(oval, 0, sweep, false);
-        REPORTER_ASSERT(reporter, p.getBounds() == oval);
+        REPORTER_ASSERT(reporter, nearly_equal(p.getBounds(), oval));
         sweep += delta;
         delta /= 2;
     }
     for (float sweep = 361, delta = 0.5f; sweep != (float) (sweep - delta);) {
         p.arcTo(oval, 0, sweep, false);
-        REPORTER_ASSERT(reporter, p.getBounds() == oval);
+        REPORTER_ASSERT(reporter, nearly_equal(p.getBounds(), oval));
         sweep -= delta;
         delta /= 2;
     }
     SkRect noOvalWidth = {1, 2, 0, 3};
     p.reset();
     p.arcTo(noOvalWidth, 0, 360, false);
     REPORTER_ASSERT(reporter, p.isEmpty());
 
     SkRect noOvalHeight = {1, 2, 3, 1};
     p.reset();
@@ skipping 477 matching lines @@
     test_addEmptyPath(reporter, SkPath::kAppend_AddPathMode);
     test_conicTo_special_case(reporter);
     test_get_point(reporter);
     test_contains(reporter);
     PathTest_Private::TestPathTo(reporter);
     PathRefTest_Private::TestPathRef(reporter);
     test_dump(reporter);
     test_path_crbugskia2820(reporter);
     test_skbug_3239(reporter);
 }