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 SkDashPathEffect_DEFINED
9 #define SkDashPathEffect_DEFINED
10 
11 #include "SkPathEffect.h"
12 
13 /** \class SkDashPathEffect
14 
15     SkDashPathEffect is a subclass of SkPathEffect that implements dashing
16 */
17 class SK_API SkDashPathEffect : public SkPathEffect {
18 public:
19     /** intervals: array containing an even number of entries (>=2), with
20          the even indices specifying the length of "on" intervals, and the odd
21          indices specifying the length of "off" intervals.
22         count: number of elements in the intervals array
23         phase: offset into the intervals array (mod the sum of all of the
24          intervals).
25 
26         For example: if intervals[] = {10, 20}, count = 2, and phase = 25,
27          this will set up a dashed path like so:
28          5 pixels off
29          10 pixels on
30          20 pixels off
31          10 pixels on
32          20 pixels off
33          ...
34         A phase of -5, 25, 55, 85, etc. would all result in the same path,
35          because the sum of all the intervals is 30.
36 
37         Note: only affects stroked paths.
38     */
39     static SkPathEffect* Create(const SkScalar intervals[], int count, SkScalar phase);
40 
41     virtual bool filterPath(SkPath* dst, const SkPath& src,
42                             SkStrokeRec*, const SkRect*) const override;
43 
44     virtual bool asPoints(PointData* results, const SkPath& src,
45                           const SkStrokeRec&, const SkMatrix&,
46                           const SkRect*) const override;
47 
48     DashType asADash(DashInfo* info) const override;
49 
50     SK_TO_STRING_OVERRIDE()
SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkDashPathEffect)51     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkDashPathEffect)
52 
53 #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
54     bool exposedInAndroidJavaAPI() const override { return true; }
55 #endif
56 
57 protected:
58     virtual ~SkDashPathEffect();
59     SkDashPathEffect(const SkScalar intervals[], int count, SkScalar phase);
60     void flatten(SkWriteBuffer&) const override;
61 
62 private:
63     SkScalar*   fIntervals;
64     int32_t     fCount;
65     SkScalar    fPhase;
66     // computed from phase
67 
68     SkScalar    fInitialDashLength;
69     int32_t     fInitialDashIndex;
70     SkScalar    fIntervalLength;
71 
72     typedef SkPathEffect INHERITED;
73 };
74 
75 #endif
76