add interp path

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 "SkGeometry.h"
 #include "SkPaint.h"
@@ skipping 3886 matching lines @@
             SkPath q;
             q.moveTo(10, 10);
             SkPathPriv::AddGenIDChangeListener(q, new ChangeListener(&changed));
             REPORTER_ASSERT(reporter, !changed);
         }
         // q went out of scope.
         REPORTER_ASSERT(reporter, changed);
     }
 };
 
+static void test_interp(skiatest::Reporter* reporter) {
+    SkPath p1, p2, out;
+    REPORTER_ASSERT(reporter, p1.isInterpolatable(p2));
+    REPORTER_ASSERT(reporter, p1.interpolate(p2, 0, &out));
+    REPORTER_ASSERT(reporter, p1 == out);
+    REPORTER_ASSERT(reporter, p1.interpolate(p2, 1, &out));
+    REPORTER_ASSERT(reporter, p1 == out);
+    p1.moveTo(0, 2);
+    p1.lineTo(0, 4);
+    REPORTER_ASSERT(reporter, !p1.isInterpolatable(p2));
+    REPORTER_ASSERT(reporter, !p1.interpolate(p2, 1, &out));
+    p2.moveTo(6, 0);
+    p2.lineTo(8, 0);
+    REPORTER_ASSERT(reporter, p1.isInterpolatable(p2));
+    REPORTER_ASSERT(reporter, p1.interpolate(p2, 0, &out));
+    REPORTER_ASSERT(reporter, p2 == out);
+    REPORTER_ASSERT(reporter, p1.interpolate(p2, 1, &out));
+    REPORTER_ASSERT(reporter, p1 == out);
+    REPORTER_ASSERT(reporter, p1.interpolate(p2, 0.5f, &out));
+    REPORTER_ASSERT(reporter, out.getBounds() == SkRect::MakeLTRB(3, 1, 4, 2));
+    p1.reset();
+    p1.moveTo(4, 4);
+    p1.conicTo(5, 4, 5, 5, 1 / SkScalarSqrt(2));
+    p2.reset();
+    p2.moveTo(4, 2);
+    p2.conicTo(7, 2, 7, 5, 1 / SkScalarSqrt(2));

[robertphillips, 2016/02/17 21:08:49]

add a test with a conic with the same points in each but different weights ?

[caryclark, 2016/02/17 21:39:21]

I intentionally didn't address this. I don't know what it means to animate the
weight, but I don't think it is a linear exercise. Also, when the weight goes to
one, the path stores a quadratic instead of a conic, so interpolation goes to
pot.

[caryclark, 2016/02/17 21:47:06]

I misunderstood the feedback. I added a test that checks to see if only the
conic weight is different, and fails in that case. (done)

+    REPORTER_ASSERT(reporter, p1.isInterpolatable(p2));
+    REPORTER_ASSERT(reporter, p1.interpolate(p2, 0.5f, &out));
+    REPORTER_ASSERT(reporter, out.getBounds() == SkRect::MakeLTRB(4, 3, 6, 5));
+    p2.reset();
+    p2.moveTo(4, 2);
+    p2.conicTo(6, 3, 6, 5, 1);
+    REPORTER_ASSERT(reporter, !p1.isInterpolatable(p2));
+}
+
+DEF_TEST(PathInterp, reporter) {
+    test_interp(reporter);
+}
+
 DEF_TEST(PathContains, reporter) {
     test_contains(reporter);
 }
 
 DEF_TEST(Paths, reporter) {
     test_path_crbug364224();
 
     SkTSize<SkScalar>::Make(3,4);
 
     SkPath  p, empty;
@@ skipping 137 matching lines @@
     PathTest_Private::TestPathTo(reporter);
     PathRefTest_Private::TestPathRef(reporter);
     PathTest_Private::TestPathrefListeners(reporter);
     test_dump(reporter);
     test_path_crbug389050(reporter);
     test_path_crbugskia2820(reporter);
     test_skbug_3469(reporter);
     test_skbug_3239(reporter);
     test_bounds_crbug_513799(reporter);
 }