1/*
2 * Copyright 2016 Google Inc.
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 Sk4fGradientBase_DEFINED
9#define Sk4fGradientBase_DEFINED
10
11#include "include/core/SkColor.h"
12#include "include/private/SkNx.h"
13#include "include/private/SkTArray.h"
14#include "src/core/SkMatrixPriv.h"
15#include "src/shaders/SkShaderBase.h"
16#include "src/shaders/gradients/Sk4fGradientPriv.h"
17#include "src/shaders/gradients/SkGradientShaderPriv.h"
18
19struct Sk4fGradientInterval {
20 Sk4fGradientInterval(const Sk4f& c0, SkScalar t0,
21 const Sk4f& c1, SkScalar t1);
22
23 bool contains(SkScalar t) const {
24 // True if t is in [p0,p1]. Note: this helper assumes a
25 // natural/increasing interval - so it's not usable in Sk4fLinearGradient.
26 SkASSERT(fT0 < fT1);
27 return t >= fT0 && t <= fT1;
28 }
29
30 // Color bias and color gradient, such that for a t in this interval
31 //
32 // C = fCb + t * fCg;
33 SkPMColor4f fCb, fCg;
34 SkScalar fT0, fT1;
35};
36
37class Sk4fGradientIntervalBuffer {
38public:
39 void init(const SkGradientShaderBase&, SkColorSpace* dstCS, SkTileMode tileMode,
40 bool premulColors, SkScalar alpha, bool reverse);
41
42 const Sk4fGradientInterval* find(SkScalar t) const;
43 const Sk4fGradientInterval* findNext(SkScalar t, const Sk4fGradientInterval* prev,
44 bool increasing) const;
45
46 using BufferType = SkSTArray<8, Sk4fGradientInterval, true>;
47
48 const BufferType* operator->() const { return &fIntervals; }
49
50private:
51 BufferType fIntervals;
52};
53
54class SkGradientShaderBase::
55GradientShaderBase4fContext : public Context {
56public:
57 GradientShaderBase4fContext(const SkGradientShaderBase&,
58 const ContextRec&);
59
60 uint32_t getFlags() const override { return fFlags; }
61
62 bool isValid() const;
63
64protected:
65 Sk4fGradientIntervalBuffer fIntervals;
66 SkMatrix fDstToPos;
67 SkMatrixPriv::MapXYProc fDstToPosProc;
68 uint8_t fFlags;
69 bool fColorsArePremul;
70 bool fDither;
71
72private:
73 using INHERITED = Context;
74
75 void addMirrorIntervals(const SkGradientShaderBase&,
76 const Sk4f& componentScale, bool reverse);
77};
78
79#endif // Sk4fGradientBase_DEFINED
80