Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(53)

Side by Side Diff: skia/ext/bitmap_platform_device_mac.cc

Issue 2616003003: Revert of Delete Mac & Cairo skia::BitmapPlatformDevice impls (Closed)
Patch Set: Created 3 years, 11 months ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View unified diff | Download patch
« no previous file with comments | « skia/ext/bitmap_platform_device_mac.h ('k') | skia/ext/bitmap_platform_device_skia.h » ('j') | no next file with comments »
Toggle Intra-line Diffs ('i') | Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
OLDNEW
(Empty)
1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "skia/ext/bitmap_platform_device_mac.h"
6
7 #import <ApplicationServices/ApplicationServices.h>
8 #include <stddef.h>
9 #include <time.h>
10
11 #include "base/mac/mac_util.h"
12 #include "base/memory/ref_counted.h"
13 #include "skia/ext/bitmap_platform_device.h"
14 #include "skia/ext/platform_canvas.h"
15 #include "skia/ext/skia_utils_mac.h"
16 #include "third_party/skia/include/core/SkMatrix.h"
17 #include "third_party/skia/include/core/SkPath.h"
18 #include "third_party/skia/include/core/SkRect.h"
19 #include "third_party/skia/include/core/SkTypes.h"
20
21 namespace skia {
22
23 namespace {
24
25 // Returns true if it is unsafe to attempt to allocate an offscreen buffer
26 // given these dimensions.
27 bool RasterDeviceTooBigToAllocate(int width, int height) {
28
29 #ifndef SKIA_EXT_RASTER_DEVICE_ALLOCATION_MAX
30 #define SKIA_EXT_RASTER_DEVICE_ALLOCATION_MAX (2 * 256 * 1024 * 1024)
31 #endif
32
33 int bytesPerPixel = 4;
34 int64_t bytes = (int64_t)width * height * bytesPerPixel;
35 return bytes > SKIA_EXT_RASTER_DEVICE_ALLOCATION_MAX;
36 }
37
38 static CGContextRef CGContextForData(void* data, int width, int height) {
39 #define HAS_ARGB_SHIFTS(a, r, g, b) \
40 (SK_A32_SHIFT == (a) && SK_R32_SHIFT == (r) \
41 && SK_G32_SHIFT == (g) && SK_B32_SHIFT == (b))
42 #if defined(SK_CPU_LENDIAN) && HAS_ARGB_SHIFTS(24, 16, 8, 0)
43 // Allocate a bitmap context with 4 components per pixel (BGRA). Apple
44 // recommends these flags for improved CG performance.
45
46 // CGBitmapContextCreate returns NULL if width/height are 0. However, our
47 // callers expect to get a canvas back (which they later resize/reallocate)
48 // so we pin the dimensions here.
49 width = SkMax32(1, width);
50 height = SkMax32(1, height);
51 CGContextRef context =
52 CGBitmapContextCreate(data, width, height, 8, width * 4,
53 base::mac::GetSystemColorSpace(),
54 kCGImageAlphaPremultipliedFirst |
55 kCGBitmapByteOrder32Host);
56 #else
57 #error We require that Skia's and CoreGraphics's recommended \
58 image memory layout match.
59 #endif
60 #undef HAS_ARGB_SHIFTS
61
62 if (!context)
63 return NULL;
64
65 // Change the coordinate system to match WebCore's
66 CGContextTranslateCTM(context, 0, height);
67 CGContextScaleCTM(context, 1.0, -1.0);
68
69 return context;
70 }
71
72 } // namespace
73
74 void BitmapPlatformDevice::ReleaseBitmapContext() {
75 SkASSERT(bitmap_context_);
76 CGContextRelease(bitmap_context_);
77 bitmap_context_ = NULL;
78 }
79
80 // Loads the specified Skia transform into the device context
81 static void LoadTransformToCGContext(CGContextRef context,
82 const SkMatrix& matrix) {
83 // CoreGraphics can concatenate transforms, but not reset the current one.
84 // So in order to get the required behavior here, we need to first make
85 // the current transformation matrix identity and only then load the new one.
86
87 // Reset matrix to identity.
88 CGAffineTransform orig_cg_matrix = CGContextGetCTM(context);
89 CGAffineTransform orig_cg_matrix_inv =
90 CGAffineTransformInvert(orig_cg_matrix);
91 CGContextConcatCTM(context, orig_cg_matrix_inv);
92
93 // assert that we have indeed returned to the identity Matrix.
94 SkASSERT(CGAffineTransformIsIdentity(CGContextGetCTM(context)));
95
96 // Convert xform to CG-land.
97 // Our coordinate system is flipped to match WebKit's so we need to modify
98 // the xform to match that.
99 SkMatrix transformed_matrix = matrix;
100 SkScalar sy = -matrix.getScaleY();
101 transformed_matrix.setScaleY(sy);
102 size_t height = CGBitmapContextGetHeight(context);
103 SkScalar ty = -matrix.getTranslateY(); // y axis is flipped.
104 transformed_matrix.setTranslateY(ty + (SkScalar)height);
105
106 CGAffineTransform cg_matrix =
107 skia::SkMatrixToCGAffineTransform(transformed_matrix);
108
109 // Load final transform into context.
110 CGContextConcatCTM(context, cg_matrix);
111 }
112
113 static void LoadClippingRegionToCGContext(CGContextRef context,
114 const SkIRect& clip_bounds,
115 const SkMatrix& transformation) {
116 // CoreGraphics applies the current transform to clip rects, which is
117 // unwanted. Inverse-transform the rect before sending it to CG. This only
118 // works for translations and scaling, but not for rotations (but the
119 // viewport is never rotated anyway).
120 SkMatrix t;
121 bool did_invert = transformation.invert(&t);
122 if (!did_invert)
123 t.reset();
124
125 SkRect rect = SkRect::Make(clip_bounds);
126 t.mapRect(&rect);
127 SkIRect irect;
128 rect.round(&irect);
129 CGContextClipToRect(context, skia::SkIRectToCGRect(irect));
130 }
131
132 void BitmapPlatformDevice::LoadConfig(const SkMatrix& transform,
133 const SkIRect& clip_bounds) {
134 if (!bitmap_context_)
135 return; // Nothing to do.
136
137 // We must restore and then save the state of the graphics context since the
138 // calls to Load the clipping region to the context are strictly cummulative,
139 // i.e., you can't replace a clip rect, other than with a save/restore.
140 // But this implies that no other changes to the state are done elsewhere.
141 // If we ever get to need to change this, then we must replace the clip rect
142 // calls in LoadClippingRegionToCGContext() with an image mask instead.
143 CGContextRestoreGState(bitmap_context_);
144 CGContextSaveGState(bitmap_context_);
145 LoadTransformToCGContext(bitmap_context_, transform);
146 LoadClippingRegionToCGContext(bitmap_context_, clip_bounds, transform);
147 }
148
149
150 // We use this static factory function instead of the regular constructor so
151 // that we can create the pixel data before calling the constructor. This is
152 // required so that we can call the base class' constructor with the pixel
153 // data.
154 BitmapPlatformDevice* BitmapPlatformDevice::Create(CGContextRef context,
155 int width,
156 int height,
157 bool is_opaque,
158 bool do_clear) {
159 if (RasterDeviceTooBigToAllocate(width, height))
160 return NULL;
161
162 SkBitmap bitmap;
163 // TODO: verify that the CG Context's pixels will have tight rowbytes or pass in the correct
164 // rowbytes for the case when context != NULL.
165 bitmap.setInfo(SkImageInfo::MakeN32(width, height, is_opaque ? kOpaque_SkAlpha Type : kPremul_SkAlphaType));
166
167 void* data;
168 if (context) {
169 data = CGBitmapContextGetData(context);
170 bitmap.setPixels(data);
171 } else {
172 if (!bitmap.tryAllocPixels())
173 return NULL;
174 data = bitmap.getPixels();
175 }
176 if (do_clear)
177 memset(data, 0, bitmap.getSafeSize());
178
179 // If we were given data, then don't clobber it!
180 #ifndef NDEBUG
181 if (!context && is_opaque) {
182 // To aid in finding bugs, we set the background color to something
183 // obviously wrong so it will be noticable when it is not cleared
184 bitmap.eraseARGB(255, 0, 255, 128); // bright bluish green
185 }
186 #endif
187
188 if (!context) {
189 context = CGContextForData(data, width, height);
190 if (!context)
191 return NULL;
192 } else
193 CGContextRetain(context);
194
195 BitmapPlatformDevice* rv = new BitmapPlatformDevice(context, bitmap);
196
197 // The device object took ownership of the graphics context with its own
198 // CGContextRetain call.
199 CGContextRelease(context);
200
201 return rv;
202 }
203
204 BitmapPlatformDevice* BitmapPlatformDevice::CreateWithData(uint8_t* data,
205 int width,
206 int height,
207 bool is_opaque) {
208 CGContextRef context = NULL;
209 if (data)
210 context = CGContextForData(data, width, height);
211
212 BitmapPlatformDevice* rv = Create(context, width, height, is_opaque, false);
213
214 // The device object took ownership of the graphics context with its own
215 // CGContextRetain call.
216 if (context)
217 CGContextRelease(context);
218
219 return rv;
220 }
221
222 // The device will own the bitmap, which corresponds to also owning the pixel
223 // data. Therefore, we do not transfer ownership to the SkBitmapDevice's bitmap.
224 BitmapPlatformDevice::BitmapPlatformDevice(
225 CGContextRef context, const SkBitmap& bitmap)
226 : SkBitmapDevice(bitmap),
227 bitmap_context_(context) {
228 SetPlatformDevice(this, this);
229 SkASSERT(bitmap_context_);
230 // Initialize the clip region to the entire bitmap.
231
232 SkIRect rect;
233 rect.set(0, 0,
234 CGBitmapContextGetWidth(bitmap_context_),
235 CGBitmapContextGetHeight(bitmap_context_));
236 CGContextRetain(bitmap_context_);
237 // We must save the state once so that we can use the restore/save trick
238 // in LoadConfig().
239 CGContextSaveGState(bitmap_context_);
240 }
241
242 BitmapPlatformDevice::~BitmapPlatformDevice() {
243 if (bitmap_context_)
244 CGContextRelease(bitmap_context_);
245 }
246
247 NativeDrawingContext BitmapPlatformDevice::BeginPlatformPaint(
248 const SkMatrix& transform,
249 const SkIRect& clip_bounds) {
250 LoadConfig(transform, clip_bounds);
251 return bitmap_context_;
252 }
253
254 SkBaseDevice* BitmapPlatformDevice::onCreateDevice(const CreateInfo& cinfo,
255 const SkPaint*) {
256 const SkImageInfo& info = cinfo.fInfo;
257 const bool do_clear = !info.isOpaque();
258 SkASSERT(info.colorType() == kN32_SkColorType);
259 return Create(NULL, info.width(), info.height(), info.isOpaque(), do_clear);
260 }
261
262 // PlatformCanvas impl
263
264 std::unique_ptr<SkCanvas> CreatePlatformCanvasWithPixels(
265 int width,
266 int height,
267 bool is_opaque,
268 uint8_t* data,
269 OnFailureType failureType) {
270 sk_sp<SkBaseDevice> dev(
271 BitmapPlatformDevice::CreateWithData(data, width, height, is_opaque));
272 return CreateCanvas(dev, failureType);
273 }
274
275 } // namespace skia
OLDNEW
« no previous file with comments | « skia/ext/bitmap_platform_device_mac.h ('k') | skia/ext/bitmap_platform_device_skia.h » ('j') | no next file with comments »

Powered by Google App Engine
This is Rietveld 408576698