1
2/*
3 * Copyright 2009 The Android Open Source Project
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8
9
10#ifndef SkEdgeClipper_DEFINED
11#define SkEdgeClipper_DEFINED
12
13#include "SkPath.h"
14
15/** This is basically an iterator. It is initialized with an edge and a clip,
16    and then next() is called until it returns kDone_Verb.
17 */
18class SkEdgeClipper {
19public:
20    SkEdgeClipper(bool canCullToTheRight) : fCanCullToTheRight(canCullToTheRight) {}
21
22    bool clipQuad(const SkPoint pts[3], const SkRect& clip);
23    bool clipCubic(const SkPoint pts[4], const SkRect& clip);
24
25    SkPath::Verb next(SkPoint pts[]);
26
27    bool canCullToTheRight() const { return fCanCullToTheRight; }
28
29private:
30    SkPoint*        fCurrPoint;
31    SkPath::Verb*   fCurrVerb;
32    const bool      fCanCullToTheRight;
33
34    enum {
35        kMaxVerbs = 13,
36        kMaxPoints = 32
37    };
38    SkPoint         fPoints[kMaxPoints];
39    SkPath::Verb    fVerbs[kMaxVerbs];
40
41    void clipMonoQuad(const SkPoint srcPts[3], const SkRect& clip);
42    void clipMonoCubic(const SkPoint srcPts[4], const SkRect& clip);
43    void appendVLine(SkScalar x, SkScalar y0, SkScalar y1, bool reverse);
44    void appendQuad(const SkPoint pts[3], bool reverse);
45    void appendCubic(const SkPoint pts[4], bool reverse);
46};
47
48#ifdef SK_DEBUG
49    void sk_assert_monotonic_x(const SkPoint pts[], int count);
50    void sk_assert_monotonic_y(const SkPoint pts[], int count);
51#else
52    #define sk_assert_monotonic_x(pts, count)
53    #define sk_assert_monotonic_y(pts, count)
54#endif
55
56#endif
57