xref: /aosp_15_r20/external/skia/include/android/SkAndroidFrameworkUtils.h (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1 /*
2  * Copyright 2017 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 SkAndroidFrameworkUtils_DEFINED
9 #define SkAndroidFrameworkUtils_DEFINED
10 
11 #include "include/core/SkColor.h"
12 #include "include/core/SkPoint.h"
13 #include "include/core/SkRefCnt.h"
14 #include "include/core/SkTileMode.h"
15 
16 #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
17 
18 class SkCanvas;
19 struct SkIRect;
20 struct SkRect;
21 class SkSurface;
22 class SkShader;
23 
24 /**
25  *  SkAndroidFrameworkUtils expose private APIs used only by Android framework.
26  */
27 class SkAndroidFrameworkUtils {
28 public:
29 
30 #if defined(SK_GANESH)
31     /**
32      *  clipWithStencil draws the current clip into a stencil buffer with reference value and mask
33      *  set to 0x1. This function works only on a GPU canvas.
34      *
35      *  @param  canvas A GPU canvas that has a non-empty clip.
36      *
37      *  @return true on success or false if clip is empty or not a GPU canvas.
38      */
39     static bool clipWithStencil(SkCanvas* canvas);
40 #endif //defined(SK_GANESH)
41 
42     static void SafetyNetLog(const char*);
43 
44     static sk_sp<SkSurface> getSurfaceFromCanvas(SkCanvas* canvas);
45 
46     static int SaveBehind(SkCanvas* canvas, const SkRect* subset);
47 
48     // Operating within the canvas' clip stack, this resets the geometry of the clip to be wide
49     // open modula any device clip restriction that was set outside of the clip stack.
50     static void ResetClip(SkCanvas* canvas);
51 
52     /**
53      * Unrolls a chain of nested SkPaintFilterCanvas to return the base wrapped canvas.
54      *
55      *  @param  canvas A SkPaintFilterCanvas or any other SkCanvas subclass.
56      *
57      *  @return SkCanvas that was found in the innermost SkPaintFilterCanvas.
58      */
59     static SkCanvas* getBaseWrappedCanvas(SkCanvas* canvas);
60 
61     /**
62      *  If the shader represents a linear gradient ShaderAsALinearGradient
63      *  returns true and if info is not null, ShaderAsALinearGradient populates
64      *  info with the parameters for the gradient. fColorCount is both an input
65      *  and output parameter. On input, it indicates how many entries in
66      *  fColors and fColorOffsets can be used, if they are not nullptr. After
67      *  asAGradient has run, fColorCount indicates how many color-offset pairs
68      *  there are in the gradient. fColorOffsets specifies where on the range of
69      *  0 to 1 to transition to the given color. fPoints represent the endpoints
70      *  of the gradient.
71      */
72     struct LinearGradientInfo {
73         int         fColorCount    = 0;        //!< In-out parameter, specifies passed size
74                                                //   of fColors/fColorOffsets on input, and
75                                                //   actual number of colors/offsets on
76                                                //   output.
77         SkColor*    fColors        = nullptr;  //!< The colors in the gradient.
78         SkScalar*   fColorOffsets  = nullptr;  //!< The unit offset for color transitions.
79         SkPoint     fPoints[2];                //!< Type specific, see above.
80         SkTileMode  fTileMode;
81         uint32_t    fGradientFlags = 0;        //!< see SkGradientShader::Flags
82     };
83 
84     static bool ShaderAsALinearGradient(SkShader* shader, LinearGradientInfo*);
85 };
86 
87 #endif // SK_BUILD_FOR_ANDROID_ANDROID
88 
89 #endif // SkAndroidFrameworkUtils_DEFINED
90