fix SkPath::contains() for points on edge, conics

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"
 #include "SkParse.h"
 #include "SkParsePath.h"
 #include "SkPathPriv.h"
 #include "SkPathEffect.h"
 #include "SkRRect.h"
 #include "SkRandom.h"
 #include "SkReader32.h"
 #include "SkSize.h"
 #include "SkStream.h"
@@ skipping 3488 matching lines @@
 
 static void test_contains(skiatest::Reporter* reporter) {
     SkPath p;
     p.setFillType(SkPath::kInverseWinding_FillType);
     REPORTER_ASSERT(reporter, p.contains(0, 0));
     p.setFillType(SkPath::kWinding_FillType);
     REPORTER_ASSERT(reporter, !p.contains(0, 0));
     p.moveTo(4, 4);
     p.lineTo(6, 8);
     p.lineTo(8, 4);
+    // test on edge
+    REPORTER_ASSERT(reporter, p.contains(6, 4));
+    REPORTER_ASSERT(reporter, p.contains(5, 6));
+    REPORTER_ASSERT(reporter, p.contains(7, 6));
     // test quick reject
     REPORTER_ASSERT(reporter, !p.contains(4, 0));
     REPORTER_ASSERT(reporter, !p.contains(0, 4));
     REPORTER_ASSERT(reporter, !p.contains(4, 10));
     REPORTER_ASSERT(reporter, !p.contains(10, 4));
     // test various crossings in x
     REPORTER_ASSERT(reporter, !p.contains(5, 7));
     REPORTER_ASSERT(reporter, p.contains(6, 7));
     REPORTER_ASSERT(reporter, !p.contains(7, 7));
     p.reset();
     p.moveTo(4, 4);
     p.lineTo(8, 6);
     p.lineTo(4, 8);
+    // test on edge
+    REPORTER_ASSERT(reporter, p.contains(4, 6));
+    REPORTER_ASSERT(reporter, p.contains(6, 5));
+    REPORTER_ASSERT(reporter, p.contains(6, 7));
     // test various crossings in y
     REPORTER_ASSERT(reporter, !p.contains(7, 5));
     REPORTER_ASSERT(reporter, p.contains(7, 6));
     REPORTER_ASSERT(reporter, !p.contains(7, 7));
+    p.reset();
+    p.moveTo(4, 4);
+    p.lineTo(6, 8);
+    p.lineTo(2, 8);
+    // test on edge
+    REPORTER_ASSERT(reporter, p.contains(5, 6));
+    REPORTER_ASSERT(reporter, p.contains(4, 8));
+    REPORTER_ASSERT(reporter, p.contains(3, 6));
+    p.reset();
+    p.moveTo(4, 4);
+    p.lineTo(0, 6);
+    p.lineTo(4, 8);
+    // test on edge
+    REPORTER_ASSERT(reporter, p.contains(2, 5));
+    REPORTER_ASSERT(reporter, p.contains(2, 7));
+    REPORTER_ASSERT(reporter, p.contains(4, 6));
+    // test canceling coincident edge (a smaller triangle is coincident with a larger one)
+    p.reset();
+    p.moveTo(4, 0);
+    p.lineTo(6, 4);
+    p.lineTo(2, 4);
+    p.moveTo(4, 0);
+    p.lineTo(0, 8);
+    p.lineTo(8, 8);
+    REPORTER_ASSERT(reporter, !p.contains(1, 2));
+    REPORTER_ASSERT(reporter, !p.contains(3, 2));
+    REPORTER_ASSERT(reporter, !p.contains(4, 0));
+    REPORTER_ASSERT(reporter, p.contains(4, 4));
+
     // test quads
     p.reset();
     p.moveTo(4, 4);
     p.quadTo(6, 6, 8, 8);
     p.quadTo(6, 8, 4, 8);
     p.quadTo(4, 6, 4, 4);
     REPORTER_ASSERT(reporter, p.contains(5, 6));
     REPORTER_ASSERT(reporter, !p.contains(6, 5));
+    // test quad edge
+    REPORTER_ASSERT(reporter, p.contains(5, 5));
+    REPORTER_ASSERT(reporter, p.contains(5, 8));
+    REPORTER_ASSERT(reporter, p.contains(4, 5));
 
     p.reset();
-    p.moveTo(6, 6);
-    p.quadTo(8, 8, 6, 8);
-    p.quadTo(4, 8, 4, 6);
-    p.quadTo(4, 4, 6, 6);
+    const SkPoint qPts[] = {{6, 6}, {8, 8}, {6, 8}, {4, 8}, {4, 6}, {4, 4}, {6, 6}};
+    p.moveTo(qPts[0]);
+    for (int index = 1; index < (int) SK_ARRAY_COUNT(qPts); index += 2) {
+        p.quadTo(qPts[index], qPts[index + 1]);
+    }
     REPORTER_ASSERT(reporter, p.contains(5, 6));
     REPORTER_ASSERT(reporter, !p.contains(6, 5));
+    // test quad edge
+    SkPoint halfway;
+    for (int index = 0; index < (int) SK_ARRAY_COUNT(qPts) - 2; index += 2) {
+        SkEvalQuadAt(&qPts[index], 0.5f, &halfway, nullptr);
+        REPORTER_ASSERT(reporter, p.contains(halfway.fX, halfway.fY));
+    }
 
-#define CONIC_CONTAINS_BUG_FIXED 0
-#if CONIC_CONTAINS_BUG_FIXED
+    // test conics
     p.reset();
-    p.moveTo(4, 4);
-    p.conicTo(6, 6, 8, 8, 0.5f);
-    p.conicTo(6, 8, 4, 8, 0.5f);
-    p.conicTo(4, 6, 4, 4, 0.5f);
+    const SkPoint kPts[] = {{4, 4}, {6, 6}, {8, 8}, {6, 8}, {4, 8}, {4, 6}, {4, 4}};
+    p.moveTo(kPts[0]);
+    for (int index = 1; index < (int) SK_ARRAY_COUNT(kPts); index += 2) {
+        p.conicTo(kPts[index], kPts[index + 1], 0.5f);
+    }
     REPORTER_ASSERT(reporter, p.contains(5, 6));
     REPORTER_ASSERT(reporter, !p.contains(6, 5));
-#endif
+    // test conic edge
+    for (int index = 0; index < (int) SK_ARRAY_COUNT(kPts) - 2; index += 2) {
+        SkConic conic(&kPts[index], 0.5f);
+        halfway = conic.evalAt(0.5f);
+        REPORTER_ASSERT(reporter, p.contains(halfway.fX, halfway.fY));
+    }
 
     // test cubics
     SkPoint pts[] = {{5, 4}, {6, 5}, {7, 6}, {6, 6}, {4, 6}, {5, 7}, {5, 5}, {5, 4}, {6, 5}, {7, 6}};
     for (int i = 0; i < 3; ++i) {
         p.reset();
         p.setFillType(SkPath::kEvenOdd_FillType);
         p.moveTo(pts[i].fX, pts[i].fY);
         p.cubicTo(pts[i + 1].fX, pts[i + 1].fY, pts[i + 2].fX, pts[i + 2].fY, pts[i + 3].fX, pts[i + 3].fY);
         p.cubicTo(pts[i + 4].fX, pts[i + 4].fY, pts[i + 5].fX, pts[i + 5].fY, pts[i + 6].fX, pts[i + 6].fY);
         p.close();
         REPORTER_ASSERT(reporter, p.contains(5.5f, 5.5f));
         REPORTER_ASSERT(reporter, !p.contains(4.5f, 5.5f));
+        // test cubic edge
+        SkEvalCubicAt(&pts[i], 0.5f, &halfway, nullptr, nullptr);
+        REPORTER_ASSERT(reporter, p.contains(halfway.fX, halfway.fY));
+        SkEvalCubicAt(&pts[i + 3], 0.5f, &halfway, nullptr, nullptr);
+        REPORTER_ASSERT(reporter, p.contains(halfway.fX, halfway.fY));
     }
 }
 
 class PathRefTest_Private {
 public:
     static void TestPathRef(skiatest::Reporter* reporter) {
         static const int kRepeatCnt = 10;
 
         SkAutoTUnref<SkPathRef> pathRef(new SkPathRef);
 
@@ skipping 206 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);
     }
 };
 
+DEF_TEST(PathContains, reporter) {
+    test_contains(reporter);
+}
+
 DEF_TEST(Paths, reporter) {
     test_path_crbug364224();
 
     SkTSize<SkScalar>::Make(3,4);
 
     SkPath  p, empty;
     SkRect  bounds, bounds2;
     test_empty(reporter, p);
 
     REPORTER_ASSERT(reporter, p.getBounds().isEmpty());
@@ skipping 132 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);
 }