xref: /aosp_15_r20/external/skia/src/gpu/ganesh/PathRendererChain.h (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1 /*
2  * Copyright 2011 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 PathRendererChain_DEFINED
9 #define PathRendererChain_DEFINED
10 
11 #include "include/core/SkRefCnt.h"
12 #include "include/core/SkTypes.h"
13 #include "include/private/base/SkNoncopyable.h"
14 #include "include/private/base/SkTArray.h"
15 #include "include/private/gpu/ganesh/GrTypesPriv.h"
16 #include "src/gpu/ganesh/PathRenderer.h"
17 #include "src/gpu/ganesh/ops/AtlasRenderTask.h"  // IWYU pragma: keep
18 
19 #include <cstddef>
20 
21 class GrRecordingContext;
22 
23 namespace skgpu::ganesh {
24 
25 class AtlasPathRenderer;
26 
27 /**
28  * Keeps track of an ordered list of path renderers. When a path needs to be
29  * drawn this list is scanned to find the most preferred renderer. To add your
30  * path renderer to the list implement the GrPathRenderer::AddPathRenderers
31  * function.
32  */
33 class PathRendererChain : public SkNoncopyable {
34 public:
35     struct Options {
36         bool fAllowPathMaskCaching = false;
37         GpuPathRenderers fGpuPathRenderers = GpuPathRenderers::kDefault;
38     };
39     PathRendererChain(GrRecordingContext*, const Options&);
40 
41     /** Documents how the caller plans to use a GrPathRenderer to draw a path. It affects the PR
42         returned by getPathRenderer */
43     enum class DrawType {
44         kColor,            // draw to the color buffer, no AA
45         kStencil,          // draw just to the stencil buffer
46         kStencilAndColor,  // draw the stencil and color buffer, no AA
47     };
48 
49     /** Returns a GrPathRenderer compatible with the request if one is available. If the caller
50         is drawing the path to the stencil buffer then stencilSupport can be used to determine
51         whether the path can be rendered with arbitrary stencil rules or not. See comments on
52         StencilSupport in GrPathRenderer.h. */
53     PathRenderer* getPathRenderer(const PathRenderer::CanDrawPathArgs&,
54                                   DrawType,
55                                   PathRenderer::StencilSupport*);
56 
57     /** Returns a direct pointer to the atlas path renderer, or null if it is not in the
58         chain. */
getAtlasPathRenderer()59     skgpu::ganesh::AtlasPathRenderer* getAtlasPathRenderer() { return fAtlasPathRenderer; }
60 
61     /** Returns a direct pointer to the tessellation path renderer, or null if it is not in the
62         chain. */
getTessellationPathRenderer()63     PathRenderer* getTessellationPathRenderer() {
64         return fTessellationPathRenderer;
65     }
66 
67 private:
68     static constexpr size_t kPreAllocCount = 8;
69 
70     skia_private::STArray<kPreAllocCount, sk_sp<PathRenderer>> fChain;
71     AtlasPathRenderer* fAtlasPathRenderer = nullptr;
72     PathRenderer* fTessellationPathRenderer = nullptr;
73 };
74 
75 }  // namespace skgpu::ganesh
76 
77 #endif // PathRendererChain_DEFINED
78