1
2/*
3 * Copyright 2012 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 SkTwoPointConicalGradient_DEFINED
10#define SkTwoPointConicalGradient_DEFINED
11
12#include "SkGradientShaderPriv.h"
13
14// TODO(dominikg): Worth making it truly immutable (i.e. set values in constructor)?
15// Should only be initialized once via init(). Immutable afterwards.
16struct TwoPtRadial {
17    enum {
18        kDontDrawT  = 0x80000000
19    };
20
21    float   fCenterX, fCenterY;
22    float   fDCenterX, fDCenterY;
23    float   fRadius;
24    float   fDRadius;
25    float   fA;
26    float   fRadius2;
27    float   fRDR;
28    bool    fFlipped;
29
30    void init(const SkPoint& center0, SkScalar rad0,
31              const SkPoint& center1, SkScalar rad1,
32              bool flipped);
33
34    static bool DontDrawT(SkFixed t) {
35        return kDontDrawT == (uint32_t)t;
36    }
37};
38
39
40class SkTwoPointConicalGradient : public SkGradientShaderBase {
41    TwoPtRadial fRec;
42public:
43    SkTwoPointConicalGradient(const SkPoint& start, SkScalar startRadius,
44                              const SkPoint& end, SkScalar endRadius,
45                              bool flippedGrad, const Descriptor&);
46
47
48    size_t contextSize() const override;
49
50    class TwoPointConicalGradientContext : public SkGradientShaderBase::GradientShaderBaseContext {
51    public:
52        TwoPointConicalGradientContext(const SkTwoPointConicalGradient&, const ContextRec&);
53        ~TwoPointConicalGradientContext() {}
54
55        void shadeSpan(int x, int y, SkPMColor dstC[], int count) override;
56
57    private:
58        typedef SkGradientShaderBase::GradientShaderBaseContext INHERITED;
59    };
60
61    virtual BitmapType asABitmap(SkBitmap* bitmap,
62                                 SkMatrix* matrix,
63                                 TileMode* xy) const override;
64    SkShader::GradientType asAGradient(GradientInfo* info) const  override;
65    virtual bool asFragmentProcessor(GrContext*, const SkPaint&, const SkMatrix&, const SkMatrix*,
66                                     GrColor*, GrFragmentProcessor**) const override;
67    bool isOpaque() const override;
68
69    SkScalar getCenterX1() const { return SkPoint::Distance(fCenter1, fCenter2); }
70    SkScalar getStartRadius() const { return fRadius1; }
71    SkScalar getDiffRadius() const { return fRadius2 - fRadius1; }
72    const SkPoint& getStartCenter() const { return fCenter1; }
73    const SkPoint& getEndCenter() const { return fCenter2; }
74    SkScalar getEndRadius() const { return fRadius2; }
75    bool isFlippedGrad() const { return fFlippedGrad; }
76
77    SK_TO_STRING_OVERRIDE()
78    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkTwoPointConicalGradient)
79
80protected:
81    SkTwoPointConicalGradient(SkReadBuffer& buffer);
82    void flatten(SkWriteBuffer& buffer) const override;
83    Context* onCreateContext(const ContextRec&, void* storage) const override;
84
85private:
86    SkPoint fCenter1;
87    SkPoint fCenter2;
88    SkScalar fRadius1;
89    SkScalar fRadius2;
90    bool fFlippedGrad;
91
92    friend class SkGradientShader;
93    typedef SkGradientShaderBase INHERITED;
94};
95
96#endif
97