aboutsummaryrefslogtreecommitdiffhomepage
path: root/src/gpu/text/GrStencilAndCoverTextContext.h
blob: dab71e057859f798ca3258ce390055d1aee57fad (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
/*
 * Copyright 2014 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef GrStencilAndCoverTextContext_DEFINED
#define GrStencilAndCoverTextContext_DEFINED

#include "GrTextContext.h"
#include "GrDrawTarget.h"
#include "GrStrokeInfo.h"
#include "SkTHash.h"
#include "SkTInternalLList.h"
#include "SkTLList.h"
#include "batches/GrDrawPathBatch.h"

class GrTextStrike;
class GrPath;
class SkSurfaceProps;

/*
 * This class implements text rendering using stencil and cover path rendering
 * (by the means of GrDrawTarget::drawPath).
 * This class exposes the functionality through GrTextContext interface.
 */
class GrStencilAndCoverTextContext : public GrTextContext {
public:
    static GrStencilAndCoverTextContext* Create(GrContext*, const SkSurfaceProps&);

    virtual ~GrStencilAndCoverTextContext();

private:
    GrStencilAndCoverTextContext(GrContext*, const SkSurfaceProps&);

    bool canDraw(const SkPaint& skPaint, const SkMatrix&) override {
        return this->internalCanDraw(skPaint);
    }

    bool internalCanDraw(const SkPaint&);

    void onDrawText(GrDrawContext*, const GrClip&, const GrPaint&, const SkPaint&,
                    const SkMatrix& viewMatrix,
                    const char text[], size_t byteLength,
                    SkScalar x, SkScalar y, const SkIRect& clipBounds) override;
    void onDrawPosText(GrDrawContext*,
                       const GrClip&, const GrPaint&, const SkPaint&,
                       const SkMatrix& viewMatrix,
                       const char text[], size_t byteLength,
                       const SkScalar pos[], int scalarsPerPosition,
                       const SkPoint& offset, const SkIRect& clipBounds) override;
    void drawTextBlob(GrDrawContext*, const GrClip&, const SkPaint&,
                      const SkMatrix& viewMatrix, const SkTextBlob*, SkScalar x, SkScalar y,
                      SkDrawFilter*, const SkIRect& clipBounds) override;

    class FallbackBlobBuilder;

    class TextRun {
    public:
        TextRun(const SkPaint& fontAndStroke);
        ~TextRun();

        void setText(const char text[], size_t byteLength, SkScalar x, SkScalar y);

        void setPosText(const char text[], size_t byteLength, const SkScalar pos[],
                        int scalarsPerPosition, const SkPoint& offset);

        void draw(GrContext*, GrDrawContext*, GrPipelineBuilder*, GrColor, const SkMatrix&,
                  SkScalar x, SkScalar y, const SkIRect& clipBounds,
                  GrTextContext* fallbackTextContext, const SkPaint& originalSkPaint) const;

        void releaseGlyphCache() const;

        size_t computeSizeInCache() const;

    private:
        typedef GrDrawPathRangeBatch::InstanceData InstanceData;

        SkGlyphCache* getGlyphCache() const;
        GrPathRange* createGlyphs(GrContext*) const;
        void appendGlyph(const SkGlyph&, const SkPoint&, FallbackBlobBuilder*);

        GrStrokeInfo                     fStroke;
        SkPaint                          fFont;
        SkScalar                         fTextRatio;
        float                            fTextInverseRatio;
        bool                             fUsingRawGlyphPaths;
        GrUniqueKey                      fGlyphPathsKey;
        int                              fTotalGlyphCount;
        SkAutoTUnref<InstanceData>       fInstanceData;
        int                              fFallbackGlyphCount;
        SkAutoTUnref<const SkTextBlob>   fFallbackTextBlob;
        mutable SkGlyphCache*            fDetachedGlyphCache;
        mutable uint32_t                 fLastDrawnGlyphsID;
    };

    // Text blobs/caches.

    class TextBlob : public SkTLList<TextRun, 1> {
    public:
        typedef SkTArray<uint32_t, true> Key;

        static const Key& GetKey(const TextBlob* blob) { return blob->key(); }

        static uint32_t Hash(const Key& key) {
            SkASSERT(key.count() > 1); // 1-length keys should be using the blob-id hash map.
            return SkChecksum::Murmur3(key.begin(), sizeof(uint32_t) * key.count());
        }

        TextBlob(uint32_t blobId, const SkTextBlob* skBlob, const SkPaint& skPaint)
            : fKey(&blobId, 1) { this->init(skBlob, skPaint); }

        TextBlob(const Key& key, const SkTextBlob* skBlob, const SkPaint& skPaint)
            : fKey(key) {
            // 1-length keys are unterstood to be the blob id and must use the other constructor.
            SkASSERT(fKey.count() > 1);
            this->init(skBlob, skPaint);
        }

        const Key& key() const { return fKey; }

        size_t cpuMemorySize() const { return fCpuMemorySize; }

    private:
        void init(const SkTextBlob*, const SkPaint&);

        const SkSTArray<1, uint32_t, true>   fKey;
        size_t                               fCpuMemorySize;

        SK_DECLARE_INTERNAL_LLIST_INTERFACE(TextBlob);
    };

    const TextBlob& findOrCreateTextBlob(const SkTextBlob*, const SkPaint&);
    void purgeToFit(const TextBlob&);

    SkTHashMap<uint32_t, TextBlob*>                           fBlobIdCache;
    SkTHashTable<TextBlob*, const TextBlob::Key&, TextBlob>   fBlobKeyCache;
    SkTInternalLList<TextBlob>                                fLRUList;
    size_t                                                    fCacheSize;

    typedef GrTextContext INHERITED;
};

#endif