add conics to path ops

src/pathops/SkPathOpsConic.h

+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkPathOpsConic_DEFINED
+#define SkPathOpsConic_DEFINED
+
+#include "SkPathOpsPoint.h"
+#include "SkPathOpsQuad.h"
+
+struct SkDConic {
+    static const int kPointCount = 3;
+    static const int kPointLast = kPointCount - 1;
+    static const int kMaxIntersections = 4;
+
+    SkDQuad fPts;
+    SkScalar fWeight;
+
+    bool collapsed() const {
+        return fPts.collapsed();
+    }
+
+    bool controlsInside() const {
+        return fPts.controlsInside();
+    }
+
+    SkDConic flip() const {
+        SkDConic result = {{{fPts[2], fPts[1], fPts[0]}}, fWeight};
+        return result;
+    }
+
+    static bool IsCubic() { return false; }
+
+    const SkDConic& set(const SkPoint pts[kPointCount], SkScalar weight) {
+        fPts.set(pts);
+        fWeight = weight;
+        return *this;
+    }
+
+    const SkDPoint& operator[](int n) const { return fPts[n]; }
+    SkDPoint& operator[](int n) { return fPts[n]; }
+
+    static int AddValidTs(double s[], int realRoots, double* t) {
+        return SkDQuad::AddValidTs(s, realRoots, t);
+    }
+
+    void align(int endIndex, SkDPoint* dstPt) const {
+        fPts.align(endIndex, dstPt);
+    }
+
+    SkDVector dxdyAtT(double t) const;
+    static int FindExtrema(const double src[], SkScalar weight, double tValue[1]);
+
+    bool hullIntersects(const SkDQuad& quad, bool* isLinear) const {
+        return fPts.hullIntersects(quad, isLinear);
+    }
+
+    bool hullIntersects(const SkDConic& conic, bool* isLinear) const {
+        return fPts.hullIntersects(conic.fPts, isLinear);
+    }
+
+    bool hullIntersects(const SkDCubic& cubic, bool* isLinear) const;
+
+    bool isLinear(int startIndex, int endIndex) const {
+        return fPts.isLinear(startIndex, endIndex);
+    }
+
+    bool monotonicInY() const {
+        return fPts.monotonicInY();
+    }
+
+    void otherPts(int oddMan, const SkDPoint* endPt[2]) const {
+        fPts.otherPts(oddMan, endPt);
+    }
+
+    SkDPoint ptAtT(double t) const;
+
+    static int RootsReal(double A, double B, double C, double t[2]) {
+        return SkDQuad::RootsReal(A, B, C, t);
+    }
+
+    static int RootsValidT(const double A, const double B, const double C, double s[2]) {
+        return SkDQuad::RootsValidT(A, B, C, s);
+    }
+
+    SkDConic subDivide(double t1, double t2) const;
+
+    static SkDConic SubDivide(const SkPoint a[kPointCount], SkScalar weight, double t1, double t2) {
+        SkDConic conic;
+        conic.set(a, weight);
+        return conic.subDivide(t1, t2);
+    }
+
+    SkDPoint subDivide(const SkDPoint& a, const SkDPoint& c, double t1, double t2,
+            SkScalar* weight) const;
+
+    static SkDPoint SubDivide(const SkPoint pts[kPointCount], SkScalar weight,
+                              const SkDPoint& a, const SkDPoint& c,
+                              double t1, double t2, SkScalar* newWeight) {
+        SkDConic conic;
+        conic.set(pts, weight);
+        return conic.subDivide(a, c, t1, t2, newWeight);
+    }
+
+    SkDPoint top(double startT, double endT) const;
+
+    // utilities callable by the user from the debugger when the implementation code is linked in
+    void dump() const;
+    void dumpID(int id) const;
+    void dumpInner() const;
+};
+
+
+#endif