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
12#include "SkFontLCDConfig.h"
13static SkPixelGeometry compute_default_geometry() {
14    SkFontLCDConfig::LCDOrder order = SkFontLCDConfig::GetSubpixelOrder();
15    if (SkFontLCDConfig::kNONE_LCDOrder == order) {
16        return kUnknown_SkPixelGeometry;
17    } else {
18        // Bit0 is RGB(0), BGR(1)
19        // Bit1 is H(0), V(1)
20        const SkPixelGeometry gGeo[] = {
21            kRGB_H_SkPixelGeometry,
22            kBGR_H_SkPixelGeometry,
23            kRGB_V_SkPixelGeometry,
24            kBGR_V_SkPixelGeometry,
25        };
26        int index = 0;
27        if (SkFontLCDConfig::kBGR_LCDOrder == order) {
28            index |= 1;
29        }
30        if (SkFontLCDConfig::kVertical_LCDOrientation == SkFontLCDConfig::GetSubpixelOrientation()){
31            index |= 2;
32        }
33        return gGeo[index];
34    }
35}
36
37SkSurfaceProps::SkSurfaceProps() : fFlags(0), fPixelGeometry(kUnknown_SkPixelGeometry) {}
38
39SkSurfaceProps::SkSurfaceProps(InitType) : fFlags(0), fPixelGeometry(compute_default_geometry()) {}
40
41SkSurfaceProps::SkSurfaceProps(uint32_t flags, InitType)
42    : fFlags(flags)
43    , fPixelGeometry(compute_default_geometry())
44{}
45
46SkSurfaceProps::SkSurfaceProps(uint32_t flags, SkPixelGeometry pg)
47    : fFlags(flags), fPixelGeometry(pg)
48{}
49
50SkSurfaceProps::SkSurfaceProps(const SkSurfaceProps& other)
51    : fFlags(other.fFlags)
52    , fPixelGeometry(other.fPixelGeometry)
53{}
54
55///////////////////////////////////////////////////////////////////////////////
56
57SkSurface_Base::SkSurface_Base(int width, int height, const SkSurfaceProps* props)
58    : INHERITED(width, height, props)
59{
60    fCachedCanvas = NULL;
61    fCachedImage = NULL;
62}
63
64SkSurface_Base::SkSurface_Base(const SkImageInfo& info, const SkSurfaceProps* props)
65    : INHERITED(info, props)
66{
67    fCachedCanvas = NULL;
68    fCachedImage = NULL;
69}
70
71SkSurface_Base::~SkSurface_Base() {
72    // in case the canvas outsurvives us, we null the callback
73    if (fCachedCanvas) {
74        fCachedCanvas->setSurfaceBase(NULL);
75    }
76
77    SkSafeUnref(fCachedImage);
78    SkSafeUnref(fCachedCanvas);
79}
80
81void SkSurface_Base::onDraw(SkCanvas* canvas, SkScalar x, SkScalar y, const SkPaint* paint) {
82    SkImage* image = this->newImageSnapshot(kYes_Budgeted);
83    if (image) {
84        canvas->drawImage(image, x, y, paint);
85        image->unref();
86    }
87}
88
89void SkSurface_Base::aboutToDraw(ContentChangeMode mode) {
90    this->dirtyGenerationID();
91
92    SkASSERT(!fCachedCanvas || fCachedCanvas->getSurfaceBase() == this);
93
94    if (fCachedImage) {
95        // the surface may need to fork its backend, if its sharing it with
96        // the cached image. Note: we only call if there is an outstanding owner
97        // on the image (besides us).
98        if (!fCachedImage->unique()) {
99            this->onCopyOnWrite(mode);
100        }
101
102        // regardless of copy-on-write, we must drop our cached image now, so
103        // that the next request will get our new contents.
104        fCachedImage->unref();
105        fCachedImage = NULL;
106    } else if (kDiscard_ContentChangeMode == mode) {
107        this->onDiscard();
108    }
109}
110
111uint32_t SkSurface_Base::newGenerationID() {
112    SkASSERT(!fCachedCanvas || fCachedCanvas->getSurfaceBase() == this);
113    static int32_t gID;
114    return sk_atomic_inc(&gID) + 1;
115}
116
117static SkSurface_Base* asSB(SkSurface* surface) {
118    return static_cast<SkSurface_Base*>(surface);
119}
120
121///////////////////////////////////////////////////////////////////////////////
122
123SkSurface::SkSurface(int width, int height, const SkSurfaceProps* props)
124    : fProps(SkSurfacePropsCopyOrDefault(props)), fWidth(width), fHeight(height)
125{
126    SkASSERT(fWidth > 0);
127    SkASSERT(fHeight > 0);
128    fGenerationID = 0;
129}
130
131SkSurface::SkSurface(const SkImageInfo& info, const SkSurfaceProps* props)
132    : fProps(SkSurfacePropsCopyOrDefault(props)), fWidth(info.width()), fHeight(info.height())
133{
134    SkASSERT(fWidth > 0);
135    SkASSERT(fHeight > 0);
136    fGenerationID = 0;
137}
138
139uint32_t SkSurface::generationID() {
140    if (0 == fGenerationID) {
141        fGenerationID = asSB(this)->newGenerationID();
142    }
143    return fGenerationID;
144}
145
146void SkSurface::notifyContentWillChange(ContentChangeMode mode) {
147    asSB(this)->aboutToDraw(mode);
148}
149
150SkCanvas* SkSurface::getCanvas() {
151    return asSB(this)->getCachedCanvas();
152}
153
154SkImage* SkSurface::newImageSnapshot(Budgeted budgeted) {
155    SkImage* image = asSB(this)->getCachedImage(budgeted);
156    SkSafeRef(image);   // the caller will call unref() to balance this
157    return image;
158}
159
160SkSurface* SkSurface::newSurface(const SkImageInfo& info) {
161    return asSB(this)->onNewSurface(info);
162}
163
164void SkSurface::draw(SkCanvas* canvas, SkScalar x, SkScalar y,
165                     const SkPaint* paint) {
166    return asSB(this)->onDraw(canvas, x, y, paint);
167}
168
169const void* SkSurface::peekPixels(SkImageInfo* info, size_t* rowBytes) {
170    return this->getCanvas()->peekPixels(info, rowBytes);
171}
172
173bool SkSurface::readPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRowBytes,
174                           int srcX, int srcY) {
175    return this->getCanvas()->readPixels(dstInfo, dstPixels, dstRowBytes, srcX, srcY);
176}
177
178//////////////////////////////////////////////////////////////////////////////////////
179
180#if !SK_SUPPORT_GPU
181
182SkSurface* SkSurface::NewRenderTargetDirect(GrRenderTarget*, const SkSurfaceProps*) {
183    return NULL;
184}
185
186SkSurface* SkSurface::NewRenderTarget(GrContext*, Budgeted, const SkImageInfo&, int,
187                                      const SkSurfaceProps*) {
188    return NULL;
189}
190
191SkSurface* SkSurface::NewWrappedRenderTarget(GrContext*, GrBackendTextureDesc,
192                                             const SkSurfaceProps*) {
193    return NULL;
194}
195
196#endif
197