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 #include "SkSurface_Base.h"
9 #include "SkImagePriv.h"
10 #include "SkCanvas.h"
11 #include "SkDevice.h"
12 #include "SkMallocPixelRef.h"
13
14 static const size_t kIgnoreRowBytesValue = (size_t)~0;
15
16 class SkSurface_Raster : public SkSurface_Base {
17 public:
18 static bool Valid(const SkImageInfo&, size_t rb = kIgnoreRowBytesValue);
19
20 SkSurface_Raster(const SkImageInfo&, void*, size_t rb,
21 void (*releaseProc)(void* pixels, void* context), void* context,
22 const SkSurfaceProps*);
23 SkSurface_Raster(SkPixelRef*, const SkSurfaceProps*);
24
25 SkCanvas* onNewCanvas() override;
26 SkSurface* onNewSurface(const SkImageInfo&) override;
27 SkImage* onNewImageSnapshot(Budgeted) override;
28 void onDraw(SkCanvas*, SkScalar x, SkScalar y, const SkPaint*) override;
29 void onCopyOnWrite(ContentChangeMode) override;
30
31 private:
32 SkBitmap fBitmap;
33 bool fWeOwnThePixels;
34
35 typedef SkSurface_Base INHERITED;
36 };
37
38 ///////////////////////////////////////////////////////////////////////////////
39
Valid(const SkImageInfo & info,size_t rowBytes)40 bool SkSurface_Raster::Valid(const SkImageInfo& info, size_t rowBytes) {
41 if (info.isEmpty()) {
42 return false;
43 }
44
45 static const size_t kMaxTotalSize = SK_MaxS32;
46
47 int shift = 0;
48 switch (info.colorType()) {
49 case kAlpha_8_SkColorType:
50 shift = 0;
51 break;
52 case kRGB_565_SkColorType:
53 shift = 1;
54 break;
55 case kN32_SkColorType:
56 shift = 2;
57 break;
58 default:
59 return false;
60 }
61
62 if (kIgnoreRowBytesValue == rowBytes) {
63 return true;
64 }
65
66 uint64_t minRB = (uint64_t)info.width() << shift;
67 if (minRB > rowBytes) {
68 return false;
69 }
70
71 size_t alignedRowBytes = rowBytes >> shift << shift;
72 if (alignedRowBytes != rowBytes) {
73 return false;
74 }
75
76 uint64_t size = sk_64_mul(info.height(), rowBytes);
77 if (size > kMaxTotalSize) {
78 return false;
79 }
80
81 return true;
82 }
83
SkSurface_Raster(const SkImageInfo & info,void * pixels,size_t rb,void (* releaseProc)(void * pixels,void * context),void * context,const SkSurfaceProps * props)84 SkSurface_Raster::SkSurface_Raster(const SkImageInfo& info, void* pixels, size_t rb,
85 void (*releaseProc)(void* pixels, void* context), void* context,
86 const SkSurfaceProps* props)
87 : INHERITED(info, props)
88 {
89 fBitmap.installPixels(info, pixels, rb, NULL, releaseProc, context);
90 fWeOwnThePixels = false; // We are "Direct"
91 }
92
SkSurface_Raster(SkPixelRef * pr,const SkSurfaceProps * props)93 SkSurface_Raster::SkSurface_Raster(SkPixelRef* pr, const SkSurfaceProps* props)
94 : INHERITED(pr->info().width(), pr->info().height(), props)
95 {
96 const SkImageInfo& info = pr->info();
97
98 fBitmap.setInfo(info, info.minRowBytes());
99 fBitmap.setPixelRef(pr);
100 fWeOwnThePixels = true;
101
102 if (!info.isOpaque()) {
103 fBitmap.eraseColor(SK_ColorTRANSPARENT);
104 }
105 }
106
onNewCanvas()107 SkCanvas* SkSurface_Raster::onNewCanvas() {
108 return SkNEW_ARGS(SkCanvas, (fBitmap, this->props()));
109 }
110
onNewSurface(const SkImageInfo & info)111 SkSurface* SkSurface_Raster::onNewSurface(const SkImageInfo& info) {
112 return SkSurface::NewRaster(info);
113 }
114
onDraw(SkCanvas * canvas,SkScalar x,SkScalar y,const SkPaint * paint)115 void SkSurface_Raster::onDraw(SkCanvas* canvas, SkScalar x, SkScalar y,
116 const SkPaint* paint) {
117 canvas->drawBitmap(fBitmap, x, y, paint);
118 }
119
onNewImageSnapshot(Budgeted)120 SkImage* SkSurface_Raster::onNewImageSnapshot(Budgeted) {
121 return SkNewImageFromBitmap(fBitmap, fWeOwnThePixels, &this->props());
122 }
123
onCopyOnWrite(ContentChangeMode mode)124 void SkSurface_Raster::onCopyOnWrite(ContentChangeMode mode) {
125 // are we sharing pixelrefs with the image?
126 SkASSERT(this->getCachedImage(kNo_Budgeted));
127 if (SkBitmapImageGetPixelRef(this->getCachedImage(kNo_Budgeted)) == fBitmap.pixelRef()) {
128 SkASSERT(fWeOwnThePixels);
129 if (kDiscard_ContentChangeMode == mode) {
130 fBitmap.setPixelRef(NULL);
131 fBitmap.allocPixels();
132 } else {
133 SkBitmap prev(fBitmap);
134 prev.deepCopyTo(&fBitmap);
135 }
136 // Now fBitmap is a deep copy of itself (and therefore different from
137 // what is being used by the image. Next we update the canvas to use
138 // this as its backend, so we can't modify the image's pixels anymore.
139 SkASSERT(this->getCachedCanvas());
140 this->getCachedCanvas()->getDevice()->replaceBitmapBackendForRasterSurface(fBitmap);
141 }
142 }
143
144 ///////////////////////////////////////////////////////////////////////////////
145
NewRasterDirectReleaseProc(const SkImageInfo & info,void * pixels,size_t rb,void (* releaseProc)(void * pixels,void * context),void * context,const SkSurfaceProps * props)146 SkSurface* SkSurface::NewRasterDirectReleaseProc(const SkImageInfo& info, void* pixels, size_t rb,
147 void (*releaseProc)(void* pixels, void* context),
148 void* context, const SkSurfaceProps* props) {
149 if (NULL == releaseProc) {
150 context = NULL;
151 }
152 if (!SkSurface_Raster::Valid(info, rb)) {
153 return NULL;
154 }
155 if (NULL == pixels) {
156 return NULL;
157 }
158
159 return SkNEW_ARGS(SkSurface_Raster, (info, pixels, rb, releaseProc, context, props));
160 }
161
NewRasterDirect(const SkImageInfo & info,void * pixels,size_t rowBytes,const SkSurfaceProps * props)162 SkSurface* SkSurface::NewRasterDirect(const SkImageInfo& info, void* pixels, size_t rowBytes,
163 const SkSurfaceProps* props) {
164 return NewRasterDirectReleaseProc(info, pixels, rowBytes, NULL, NULL, props);
165 }
166
NewRaster(const SkImageInfo & info,const SkSurfaceProps * props)167 SkSurface* SkSurface::NewRaster(const SkImageInfo& info, const SkSurfaceProps* props) {
168 if (!SkSurface_Raster::Valid(info)) {
169 return NULL;
170 }
171
172 SkAutoTUnref<SkPixelRef> pr(SkMallocPixelRef::NewAllocate(info, 0, NULL));
173 if (NULL == pr.get()) {
174 return NULL;
175 }
176 return SkNEW_ARGS(SkSurface_Raster, (pr, props));
177 }
178