Sk1DPathEffect.h revision 0a2bf90dccba3bde188e0386a7f0c60e6dde1ae9 
1/*
2 * Copyright 2006 The Android Open Source Project
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#ifndef Sk1DPathEffect_DEFINED
9#define Sk1DPathEffect_DEFINED
10
11#include "SkPathEffect.h"
12#include "SkPath.h"
13
14class SkPathMeasure;
15
16// This class is not exported to java.
17class SK_API Sk1DPathEffect : public SkPathEffect {
18public:
19    virtual bool filterPath(SkPath* dst, const SkPath& src,
20                            SkStrokeRec*, const SkRect*) const SK_OVERRIDE;
21
22protected:
23    /** Called at the start of each contour, returns the initial offset
24        into that contour.
25    */
26    virtual SkScalar begin(SkScalar contourLength) const = 0;
27    /** Called with the current distance along the path, with the current matrix
28        for the point/tangent at the specified distance.
29        Return the distance to travel for the next call. If return <= 0, then that
30        contour is done.
31    */
32    virtual SkScalar next(SkPath* dst, SkScalar dist, SkPathMeasure&) const = 0;
33
34private:
35    typedef SkPathEffect INHERITED;
36};
37
38class SK_API SkPath1DPathEffect : public Sk1DPathEffect {
39public:
40    enum Style {
41        kTranslate_Style,   // translate the shape to each position
42        kRotate_Style,      // rotate the shape about its center
43        kMorph_Style,       // transform each point, and turn lines into curves
44
45        kStyleCount
46    };
47
48    /** Dash by replicating the specified path.
49        @param path The path to replicate (dash)
50        @param advance The space between instances of path
51        @param phase distance (mod advance) along path for its initial position
52        @param style how to transform path at each point (based on the current
53                     position and tangent)
54    */
55    static SkPath1DPathEffect* Create(const SkPath& path, SkScalar advance, SkScalar phase,
56                                      Style style) {
57        return SkNEW_ARGS(SkPath1DPathEffect, (path, advance, phase, style));
58    }
59
60    virtual bool filterPath(SkPath*, const SkPath&,
61                            SkStrokeRec*, const SkRect*) const SK_OVERRIDE;
62
63    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkPath1DPathEffect)
64
65protected:
66    SkPath1DPathEffect(SkReadBuffer& buffer);
67    virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
68
69    // overrides from Sk1DPathEffect
70    virtual SkScalar begin(SkScalar contourLength) const SK_OVERRIDE;
71    virtual SkScalar next(SkPath*, SkScalar, SkPathMeasure&) const SK_OVERRIDE;
72
73#ifdef SK_SUPPORT_LEGACY_PUBLICEFFECTCONSTRUCTORS
74public:
75#endif
76    SkPath1DPathEffect(const SkPath& path, SkScalar advance, SkScalar phase, Style);
77
78private:
79    SkPath      fPath;          // copied from constructor
80    SkScalar    fAdvance;       // copied from constructor
81    SkScalar    fInitialOffset; // computed from phase
82    Style       fStyle;         // copied from constructor
83
84    typedef Sk1DPathEffect INHERITED;
85};
86
87#endif
88