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 #ifndef GrClipStackClip_DEFINED
8 #define GrClipStackClip_DEFINED
9 
10 #include "src/core/SkClipStack.h"
11 #include "src/gpu/GrClip.h"
12 #include "src/gpu/GrReducedClip.h"
13 
14 class GrPathRenderer;
15 class GrTextureProxy;
16 
17 /**
18  * GrClipStackClip can apply a generic SkClipStack to the draw state. It may need to generate an
19  * 8-bit alpha clip mask and/or modify the stencil buffer during apply().
20  */
21 class GrClipStackClip final : public GrClip {
22 public:
23     GrClipStackClip(const SkISize& dimensions,
24                     const SkClipStack* stack = nullptr,
25                     const SkMatrixProvider* matrixProvider = nullptr)
fDeviceSize(dimensions)26             : fDeviceSize(dimensions)
27             , fStack(stack)
28             , fMatrixProvider(matrixProvider) {}
29 
30     SkIRect getConservativeBounds() const final;
31     Effect apply(GrRecordingContext*, GrSurfaceDrawContext*, GrAAType aaType,
32                      bool hasUserStencilSettings, GrAppliedClip* out, SkRect* bounds) const final;
33     PreClipResult preApply(const SkRect& drawBounds, GrAA aa) const final;
34 
35     sk_sp<GrTextureProxy> testingOnly_createClipMask(GrRecordingContext*) const;
36     static const char kMaskTestTag[];
37 
38 private:
39     static bool PathNeedsSWRenderer(GrRecordingContext* context,
40                                     const SkIRect& scissorRect,
41                                     bool hasUserStencilSettings,
42                                     const GrSurfaceDrawContext*,
43                                     const SkMatrix& viewMatrix,
44                                     const SkClipStack::Element* element,
45                                     bool needsStencil);
46 
47     bool applyClipMask(GrRecordingContext*, GrSurfaceDrawContext*, const GrReducedClip&,
48                        bool hasUserStencilSettings, GrAppliedClip*) const;
49 
50     // Creates an alpha mask of the clip. The mask is a rasterization of elements through the
51     // rect specified by clipSpaceIBounds.
52     GrSurfaceProxyView createAlphaClipMask(GrRecordingContext*, const GrReducedClip&) const;
53 
54     // Similar to createAlphaClipMask but it rasterizes in SW and uploads to the result texture.
55     GrSurfaceProxyView createSoftwareClipMask(GrRecordingContext*, const GrReducedClip&,
56                                               GrSurfaceDrawContext*) const;
57 
58     static bool UseSWOnlyPath(GrRecordingContext*,
59                               bool hasUserStencilSettings,
60                               const GrSurfaceDrawContext*,
61                               const GrReducedClip&);
62 
63     // SkClipStack does not track device bounds explicitly, but it will refine these device bounds
64     // as clip elements are added to the stack.
65     SkISize                 fDeviceSize;
66     const SkClipStack*      fStack;
67     const SkMatrixProvider* fMatrixProvider; // for applying clip shaders
68 };
69 
70 #endif // GrClipStackClip_DEFINED
71