add conics to path ops

tests/PathOpsConicIntersectionTest.cpp

+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+#include "PathOpsTestCommon.h"
+#include "SkGeometry.h"
+#include "SkIntersections.h"
+#include "Test.h"
+
+/*
+manually compute the intersection of a pair of circles and see if the conic intersection matches
+  given two circles
+    construct a line connecting their centers
+    
+ */
+
+static const SkDConic testSet[] = {
+    {{{{-4,1}, {-4,5}, {0,5}}}, 0.707106769f},
+    {{{{-3,4}, {-3,1}, {0,1}}}, 0.707106769f},
+
+    {{{{0, 0}, {0, 1}, {1, 1}}}, 0.5f},
+    {{{{1, 0}, {0, 0}, {0, 1}}}, 0.5f},
+};
+
+const int testSetCount = (int) SK_ARRAY_COUNT(testSet);
+
+static void oneOff(skiatest::Reporter* reporter, const SkDConic& c1, const SkDConic& c2,
+        bool coin) {
+    SkASSERT(ValidConic(c1));
+    SkASSERT(ValidConic(c2));
+    SkIntersections intersections;
+    intersections.intersect(c1, c2);
+    if (coin && intersections.used() != 2) {
+        SkDebugf("");
+    }
+    REPORTER_ASSERT(reporter, !coin || intersections.used() == 2);
+    double tt1, tt2;
+    SkDPoint xy1, xy2;
+    for (int pt3 = 0; pt3 < intersections.used(); ++pt3) {
+        tt1 = intersections[0][pt3];
+        xy1 = c1.ptAtT(tt1);
+        tt2 = intersections[1][pt3];
+        xy2 = c2.ptAtT(tt2);
+        const SkDPoint& iPt = intersections.pt(pt3);
+        REPORTER_ASSERT(reporter, xy1.approximatelyEqual(iPt));
+        REPORTER_ASSERT(reporter, xy2.approximatelyEqual(iPt));
+        REPORTER_ASSERT(reporter, xy1.approximatelyEqual(xy2));
+    }
+    reporter->bumpTestCount();
+}
+
+static void oneOff(skiatest::Reporter* reporter, int outer, int inner) {
+    const SkDConic& c1 = testSet[outer];
+    const SkDConic& c2 = testSet[inner];
+    oneOff(reporter, c1, c2, false);
+}
+
+static void oneOffTests(skiatest::Reporter* reporter) {
+    for (int outer = 0; outer < testSetCount - 1; ++outer) {
+        for (int inner = outer + 1; inner < testSetCount; ++inner) {
+            oneOff(reporter, outer, inner);
+        }
+    }
+}
+
+DEF_TEST(PathOpsConicIntersectionOneOff, reporter) {
+    oneOff(reporter, 0, 1);
+}
+
+DEF_TEST(PathOpsConicIntersection, reporter) {
+    oneOffTests(reporter);
+}