1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
|
// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <windows.h>
#include <psapi.h>
#include <stddef.h>
#include <string.h>
#include "base/check_op.h"
#include "base/compiler_specific.h"
#include "base/debug/gdi_debug_util_win.h"
#include "base/logging.h"
#include "base/memory/ptr_util.h"
#include "base/win/scoped_gdi_object.h"
#include "base/win/win_util.h"
#include "skia/ext/legacy_display_globals.h"
#include "skia/ext/platform_canvas.h"
#include "skia/ext/skia_utils_win.h"
#include "third_party/skia/include/core/SkMatrix.h"
#include "third_party/skia/include/core/SkPath.h"
#include "third_party/skia/include/core/SkRect.h"
#include "third_party/skia/include/core/SkRefCnt.h"
namespace {
struct HDCContextRec {
HDC hdc_;
HBITMAP prev_bitmap_;
};
static void DeleteHDCCallback(void*, void* context) {
DCHECK_NE(context, nullptr);
const HDCContextRec* rec = static_cast<const HDCContextRec*>(context);
// Must select back in the old bitmap before we delete the hdc, and so we can
// recover the new_bitmap that we allocated, so we can delete it.
DeleteObject(
static_cast<HBITMAP>(SelectObject(rec->hdc_, rec->prev_bitmap_)));
DeleteDC(rec->hdc_);
delete rec;
}
// Allocate the layer and fill in the fields for the Rec, or return false
// on error.
static bool Create(int width,
int height,
HANDLE shared_section,
bool do_clear,
SkRasterHandleAllocator::Rec* rec) {
void* pixels;
base::win::ScopedGDIObject<HBITMAP> new_bitmap =
skia::CreateHBitmapXRGB8888(width, height, shared_section, &pixels);
if (!new_bitmap.is_valid()) {
LOG(ERROR) << "CreateHBitmap failed";
return false;
}
// The HBITMAP is 32-bit RGB data. A size_t causes a type change from int when
// multiplying against the dimensions.
const size_t bpp = 4;
if (do_clear) {
UNSAFE_TODO(memset(pixels, 0, width * bpp * height));
}
HDC hdc = CreateCompatibleDC(nullptr);
if (!hdc)
return false;
SetGraphicsMode(hdc, GM_ADVANCED);
// The |new_bitmap| will be destroyed by |rec|'s DeleteHDCCallback().
HBITMAP prev_bitmap =
static_cast<HBITMAP>(SelectObject(hdc, new_bitmap.release()));
DCHECK(prev_bitmap);
rec->fReleaseProc = DeleteHDCCallback;
rec->fReleaseCtx = new HDCContextRec{hdc, prev_bitmap};
rec->fPixels = pixels;
rec->fRowBytes = width * bpp;
rec->fHandle = hdc;
return true;
}
/**
* Subclass of SkRasterHandleAllocator that returns an HDC as its "handle".
*/
class GDIAllocator : public SkRasterHandleAllocator {
public:
GDIAllocator() {}
bool allocHandle(const SkImageInfo& info, Rec* rec) override {
SkASSERT(info.colorType() == kN32_SkColorType);
return Create(info.width(), info.height(), nullptr, !info.isOpaque(), rec);
}
void updateHandle(Handle handle,
const SkMatrix& ctm,
const SkIRect& clip_bounds) override {
HDC hdc = static_cast<HDC>(handle);
skia::LoadTransformToDC(hdc, ctm);
base::win::ScopedGDIObject<HRGN> hrgn(
CreateRectRgnIndirect(&skia::SkIRectToRECT(clip_bounds)));
SelectClipRgn(hdc, hrgn.get());
}
};
void unmap_view_proc(void* pixels, void*) {
UnmapViewOfFile(pixels);
}
} // namespace
namespace skia {
std::unique_ptr<SkCanvas> CreatePlatformCanvasWithSharedSection(
int width,
int height,
bool is_opaque,
HANDLE shared_section,
OnFailureType failure_type) {
SkAlphaType alpha = is_opaque ? kOpaque_SkAlphaType : kPremul_SkAlphaType;
SkImageInfo info = SkImageInfo::MakeN32(width, height, alpha);
// 32-bit RGB data as we're using N32 |info|. A size_t causes a type change
// from int when multiplying against the dimensions.
const size_t bpp = 4;
// This function contains an implementation of a Skia platform bitmap for
// drawing and compositing graphics. The original implementation uses Windows
// GDI to create the backing bitmap memory, however it's possible for a
// process to not have access to GDI which will cause this code to fail. It's
// possible to detect when GDI is unavailable and instead directly map the
// shared memory as the bitmap.
if (base::win::IsUser32AndGdi32Available()) {
SkRasterHandleAllocator::Rec rec;
if (Create(width, height, shared_section, false, &rec))
return SkRasterHandleAllocator::MakeCanvas(
std::make_unique<GDIAllocator>(), info, &rec);
} else {
DCHECK(shared_section != NULL);
void* pixels = MapViewOfFile(shared_section, FILE_MAP_WRITE, 0, 0,
width * bpp * height);
if (pixels) {
SkBitmap bitmap;
if (bitmap.installPixels(info, pixels, width * bpp, unmap_view_proc,
nullptr)) {
return std::make_unique<SkCanvas>(
bitmap, LegacyDisplayGlobals::GetSkSurfaceProps());
}
}
}
CHECK(failure_type != CRASH_ON_FAILURE);
return nullptr;
}
HDC GetNativeDrawingContext(SkCanvas* canvas) {
return canvas ? static_cast<HDC>(canvas->accessTopRasterHandle()) : nullptr;
}
} // namespace skia
|
