1 /*
2 * Copyright 2012 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 SkSurface_Base_DEFINED
9 #define SkSurface_Base_DEFINED
10
11 #include "include/core/SkCanvas.h"
12 #include "include/core/SkDeferredDisplayList.h"
13 #include "include/core/SkSurface.h"
14 #include "src/core/SkImagePriv.h"
15 #include "src/core/SkSurfacePriv.h"
16
17 class SkSurface_Base : public SkSurface {
18 public:
19 SkSurface_Base(int width, int height, const SkSurfaceProps*);
20 SkSurface_Base(const SkImageInfo&, const SkSurfaceProps*);
21 ~SkSurface_Base() override;
22
23 virtual GrRecordingContext* onGetRecordingContext();
24 virtual skgpu::graphite::Recorder* onGetRecorder();
25
26 #if defined(SK_GANESH)
27 virtual GrBackendTexture onGetBackendTexture(BackendHandleAccess);
28 virtual GrBackendRenderTarget onGetBackendRenderTarget(BackendHandleAccess);
29 virtual bool onReplaceBackendTexture(const GrBackendTexture&,
30 GrSurfaceOrigin,
31 ContentChangeMode,
32 TextureReleaseProc,
33 ReleaseContext);
34
onResolveMSAA()35 virtual void onResolveMSAA() {}
36
37 /**
38 * Issue any pending surface IO to the current backend 3D API and resolve any surface MSAA.
39 * Inserts the requested number of semaphores for the gpu to signal when work is complete on the
40 * gpu and inits the array of GrBackendSemaphores with the signaled semaphores.
41 */
onFlush(BackendSurfaceAccess access,const GrFlushInfo &,const skgpu::MutableTextureState *)42 virtual GrSemaphoresSubmitted onFlush(BackendSurfaceAccess access, const GrFlushInfo&,
43 const skgpu::MutableTextureState*) {
44 return GrSemaphoresSubmitted::kNo;
45 }
46 #endif
47
48 /**
49 * Allocate a canvas that will draw into this surface. We will cache this
50 * canvas, to return the same object to the caller multiple times. We
51 * take ownership, and will call unref() on the canvas when we go out of
52 * scope.
53 */
54 virtual SkCanvas* onNewCanvas() = 0;
55
56 virtual sk_sp<SkSurface> onNewSurface(const SkImageInfo&) = 0;
57
58 /**
59 * Allocate an SkImage that represents the current contents of the surface.
60 * This needs to be able to outlive the surface itself (if need be), and
61 * must faithfully represent the current contents, even if the surface
62 * is changed after this called (e.g. it is drawn to via its canvas).
63 *
64 * If a subset is specified, the the impl must make a copy, rather than try to wait
65 * on copy-on-write.
66 */
67 virtual sk_sp<SkImage> onNewImageSnapshot(const SkIRect* subset = nullptr) { return nullptr; }
68
69 #if defined(SK_GRAPHITE)
onAsImage()70 virtual sk_sp<SkImage> onAsImage() { return nullptr; }
71
onMakeImageCopy(const SkIRect *,skgpu::Mipmapped)72 virtual sk_sp<SkImage> onMakeImageCopy(const SkIRect* /* subset */,
73 skgpu::Mipmapped) {
74 return nullptr;
75 }
76 #endif
77
78 virtual void onWritePixels(const SkPixmap&, int x, int y) = 0;
79
80 /**
81 * Default implementation does a rescale/read and then calls the callback.
82 */
83 virtual void onAsyncRescaleAndReadPixels(const SkImageInfo&,
84 const SkIRect srcRect,
85 RescaleGamma,
86 RescaleMode,
87 ReadPixelsCallback,
88 ReadPixelsContext);
89 /**
90 * Default implementation does a rescale/read/yuv conversion and then calls the callback.
91 */
92 virtual void onAsyncRescaleAndReadPixelsYUV420(SkYUVColorSpace,
93 sk_sp<SkColorSpace> dstColorSpace,
94 SkIRect srcRect,
95 SkISize dstSize,
96 RescaleGamma,
97 RescaleMode,
98 ReadPixelsCallback,
99 ReadPixelsContext);
100
101 /**
102 * Default implementation:
103 *
104 * image = this->newImageSnapshot();
105 * if (image) {
106 * image->draw(canvas, ...);
107 * image->unref();
108 * }
109 */
110 virtual void onDraw(SkCanvas*, SkScalar x, SkScalar y, const SkSamplingOptions&,const SkPaint*);
111
112 /**
113 * Called as a performance hint when the Surface is allowed to make it's contents
114 * undefined.
115 */
onDiscard()116 virtual void onDiscard() {}
117
118 /**
119 * If the surface is about to change, we call this so that our subclass
120 * can optionally fork their backend (copy-on-write) in case it was
121 * being shared with the cachedImage.
122 *
123 * Returns false if the backing cannot be un-shared.
124 */
125 virtual bool SK_WARN_UNUSED_RESULT onCopyOnWrite(ContentChangeMode) = 0;
126
127 /**
128 * Signal the surface to remind its backing store that it's mutable again.
129 * Called only when we _didn't_ copy-on-write; we assume the copies start mutable.
130 */
onRestoreBackingMutability()131 virtual void onRestoreBackingMutability() {}
132
133 /**
134 * Caused the current backend 3D API to wait on the passed in semaphores before executing new
135 * commands on the gpu. Any previously submitting commands will not be blocked by these
136 * semaphores.
137 */
onWait(int numSemaphores,const GrBackendSemaphore * waitSemaphores,bool deleteSemaphoresAfterWait)138 virtual bool onWait(int numSemaphores, const GrBackendSemaphore* waitSemaphores,
139 bool deleteSemaphoresAfterWait) {
140 return false;
141 }
142
onCharacterize(SkSurfaceCharacterization *)143 virtual bool onCharacterize(SkSurfaceCharacterization*) const { return false; }
onIsCompatible(const SkSurfaceCharacterization &)144 virtual bool onIsCompatible(const SkSurfaceCharacterization&) const { return false; }
onDraw(sk_sp<const SkDeferredDisplayList>,SkIPoint offset)145 virtual bool onDraw(sk_sp<const SkDeferredDisplayList>, SkIPoint offset) {
146 return false;
147 }
148
149 // TODO: Remove this (make it pure virtual) after updating Android (which has a class derived
150 // from SkSurface_Base).
151 virtual sk_sp<const SkCapabilities> onCapabilities();
152
153 // True for surfaces instantiated by Graphite in GPU memory
isGraphiteBacked()154 virtual bool isGraphiteBacked() const { return false; }
155
156 inline SkCanvas* getCachedCanvas();
157 inline sk_sp<SkImage> refCachedImage();
158
hasCachedImage()159 bool hasCachedImage() const { return fCachedImage != nullptr; }
160
161 // called by SkSurface to compute a new genID
162 uint32_t newGenerationID();
163
164 private:
165 std::unique_ptr<SkCanvas> fCachedCanvas;
166 sk_sp<SkImage> fCachedImage;
167
168 // Returns false if drawing should not take place (allocation failure).
169 bool SK_WARN_UNUSED_RESULT aboutToDraw(ContentChangeMode mode);
170
171 // Returns true if there is an outstanding image-snapshot, indicating that a call to aboutToDraw
172 // would trigger a copy-on-write.
173 bool outstandingImageSnapshot() const;
174
175 friend class SkCanvas;
176 friend class SkSurface;
177
178 using INHERITED = SkSurface;
179 };
180
getCachedCanvas()181 SkCanvas* SkSurface_Base::getCachedCanvas() {
182 if (nullptr == fCachedCanvas) {
183 fCachedCanvas = std::unique_ptr<SkCanvas>(this->onNewCanvas());
184 if (fCachedCanvas) {
185 fCachedCanvas->setSurfaceBase(this);
186 }
187 }
188 return fCachedCanvas.get();
189 }
190
refCachedImage()191 sk_sp<SkImage> SkSurface_Base::refCachedImage() {
192 if (fCachedImage) {
193 return fCachedImage;
194 }
195
196 fCachedImage = this->onNewImageSnapshot();
197
198 SkASSERT(!fCachedCanvas || fCachedCanvas->getSurfaceBase() == this);
199 return fCachedImage;
200 }
201
202 #endif
203