SkAAClip.h revision 322878907f6c5c5fb8abdbce7d348a3cd66ff2fa 
1
2/*
3 * Copyright 2011 Google Inc.
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#ifndef SkAAClip_DEFINED
10#define SkAAClip_DEFINED
11
12#include "SkBlitter.h"
13#include "SkRegion.h"
14
15#define SkAAClip_gEmptyPtr   ((SkAAClip::RunHead*)-1)
16#define SkAAClip_gRectPtr    NULL
17
18class SkAAClip {
19public:
20    SkAAClip();
21    SkAAClip(const SkAAClip&);
22    ~SkAAClip();
23
24    SkAAClip& operator=(const SkAAClip&);
25    friend bool operator==(const SkAAClip&, const SkAAClip&);
26    friend bool operator!=(const SkAAClip& a, const SkAAClip& b) {
27        return !(a == b);
28    }
29
30    void swap(SkAAClip&);
31
32    bool isEmpty() const { return SkAAClip_gEmptyPtr == fRunHead; }
33//    bool isRect() const { return SkAAClip_gRectPtr == fRunHead; }
34    bool isComplex() const { return !this->isEmpty() /*&& !this->isRect()*/; }
35    const SkIRect& getBounds() const { return fBounds; }
36
37    bool setEmpty();
38    bool setRect(const SkIRect&);
39    bool setRect(const SkRect&);
40    bool setPath(const SkPath&, const SkRegion* clip = NULL);
41    bool set(const SkAAClip&);
42
43    bool op(const SkAAClip&, const SkAAClip&, SkRegion::Op);
44
45    /**
46     *  Allocates a mask the size of the aaclip, and expands its data into
47     *  the mask, using kA8_Format
48     */
49    void copyToMask(SkMask*) const;
50
51    // called internally
52
53    bool quickContains(int left, int top, int right, int bottom) const;
54    const uint8_t* findRow(int y, int* lastYForRow) const;
55    const uint8_t* findX(const uint8_t data[], int x, int* initialCount) const;
56
57    class Iter;
58    struct RunHead;
59    struct YOffset;
60    class Builder;
61
62private:
63    SkIRect  fBounds;
64    RunHead* fRunHead;
65
66    void freeRuns();
67
68    friend class Builder;
69    class BuilderBlitter;
70    friend class BuilderBlitter;
71};
72
73///////////////////////////////////////////////////////////////////////////////
74
75class SkAAClipBlitter : public SkBlitter {
76public:
77    SkAAClipBlitter() : fRuns(NULL) {}
78    virtual ~SkAAClipBlitter();
79
80    void init(SkBlitter* blitter, const SkAAClip* aaclip) {
81        SkASSERT(aaclip && !aaclip->isEmpty());
82        fBlitter = blitter;
83        fAAClip = aaclip;
84        fAAClipBounds = aaclip->getBounds();
85    }
86
87    virtual void blitH(int x, int y, int width) SK_OVERRIDE;
88    virtual void blitAntiH(int x, int y, const SkAlpha[],
89                           const int16_t runs[]) SK_OVERRIDE;
90    virtual void blitV(int x, int y, int height, SkAlpha alpha) SK_OVERRIDE;
91    virtual void blitRect(int x, int y, int width, int height) SK_OVERRIDE;
92    virtual void blitMask(const SkMask&, const SkIRect& clip) SK_OVERRIDE;
93    virtual const SkBitmap* justAnOpaqueColor(uint32_t* value) SK_OVERRIDE;
94
95private:
96    SkBlitter*      fBlitter;
97    const SkAAClip* fAAClip;
98    SkIRect         fAAClipBounds;
99
100    // lazily allocated
101    int16_t*        fRuns;
102    SkAlpha*        fAA;    // points into fRuns allocation
103
104    void ensureRunsAndAA();
105};
106
107#endif
108