3 * Copyright 2013 Google Inc.
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
9 #ifndef SkBitmapDevice_DEFINED
10 #define SkBitmapDevice_DEFINED
14 ///////////////////////////////////////////////////////////////////////////////
15 class SK_API SkBitmapDevice : public SkBaseDevice {
17 SK_DECLARE_INST_COUNT(SkBitmapDevice)
20 * Construct a new device with the specified bitmap as its backend. It is
21 * valid for the bitmap to have no pixels associated with it. In that case,
22 * any drawing to this device will have no effect.
24 SkBitmapDevice(const SkBitmap& bitmap);
27 * Construct a new device with the specified bitmap as its backend. It is
28 * valid for the bitmap to have no pixels associated with it. In that case,
29 * any drawing to this device will have no effect.
31 SkBitmapDevice(const SkBitmap& bitmap, const SkDeviceProperties& deviceProperties);
34 * Create a new raster device and have the pixels be automatically
35 * allocated. The rowBytes of the device will be computed automatically
36 * based on the config and the width.
38 * @param config The desired config for the pixels. If the request cannot
39 * be met, the closest matching support config will be used.
40 * @param width width (in pixels) of the device
41 * @param height height (in pixels) of the device
42 * @param isOpaque Set to true if it is known that all of the pixels will
43 * be drawn to opaquely. Used as an accelerator when drawing
44 * these pixels to another device.
46 SkBitmapDevice(SkBitmap::Config config, int width, int height, bool isOpaque = false);
49 * Create a new raster device and have the pixels be automatically
50 * allocated. The rowBytes of the device will be computed automatically
51 * based on the config and the width.
53 * @param config The desired config for the pixels. If the request cannot
54 * be met, the closest matching support config will be used.
55 * @param width width (in pixels) of the device
56 * @param height height (in pixels) of the device
57 * @param isOpaque Set to true if it is known that all of the pixels will
58 * be drawn to opaquely. Used as an accelerator when drawing
59 * these pixels to another device.
60 * @param deviceProperties Properties which affect compositing.
62 SkBitmapDevice(SkBitmap::Config config, int width, int height, bool isOpaque,
63 const SkDeviceProperties& deviceProperties);
65 virtual ~SkBitmapDevice();
67 virtual uint32_t getDeviceCapabilities() SK_OVERRIDE { return 0; }
69 /** Return the width of the device (in pixels).
71 virtual int width() const SK_OVERRIDE { return fBitmap.width(); }
72 /** Return the height of the device (in pixels).
74 virtual int height() const SK_OVERRIDE { return fBitmap.height(); }
76 /** Returns true if the device's bitmap's config treats every pixels as
79 virtual bool isOpaque() const SK_OVERRIDE { return fBitmap.isOpaque(); }
81 /** Return the bitmap config of the device's pixels
83 virtual SkBitmap::Config config() const SK_OVERRIDE { return fBitmap.config(); }
85 virtual SkImageInfo imageInfo() const SK_OVERRIDE;
88 * DEPRECATED: This will be made protected once WebKit stops using it.
89 * Instead use Canvas' writePixels method.
91 * Similar to draw sprite, this method will copy the pixels in bitmap onto
92 * the device, with the top/left corner specified by (x, y). The pixel
93 * values in the device are completely replaced: there is no blending.
95 * Currently if bitmap is backed by a texture this is a no-op. This may be
96 * relaxed in the future.
98 * If the bitmap has config kARGB_8888_Config then the config8888 param
99 * will determines how the pixel valuess are intepreted. If the bitmap is
100 * not kARGB_8888_Config then this parameter is ignored.
102 virtual void writePixels(const SkBitmap& bitmap, int x, int y,
103 SkCanvas::Config8888 config8888) SK_OVERRIDE;
106 * Return the device's associated gpu render target, or NULL.
108 virtual GrRenderTarget* accessRenderTarget() SK_OVERRIDE { return NULL; }
112 * Device may filter the text flags for drawing text here. If it wants to
113 * make a change to the specified values, it should write them into the
114 * textflags parameter (output) and return true. If the paint is fine as
115 * is, then ignore the textflags parameter and return false.
117 * The baseclass SkDevice filters based on its depth and blitters.
119 virtual bool filterTextFlags(const SkPaint& paint, TextFlags*) SK_OVERRIDE;
121 /** Clears the entire device to the specified color (including alpha).
124 virtual void clear(SkColor color) SK_OVERRIDE;
126 /** These are called inside the per-device-layer loop for each draw call.
127 When these are called, we have already applied any saveLayer operations,
128 and are handling any looping from the paint, and any effects from the
131 virtual void drawPaint(const SkDraw&, const SkPaint& paint) SK_OVERRIDE;
132 virtual void drawPoints(const SkDraw&, SkCanvas::PointMode mode, size_t count,
133 const SkPoint[], const SkPaint& paint) SK_OVERRIDE;
134 virtual void drawRect(const SkDraw&, const SkRect& r,
135 const SkPaint& paint) SK_OVERRIDE;
136 virtual void drawOval(const SkDraw&, const SkRect& oval,
137 const SkPaint& paint) SK_OVERRIDE;
138 virtual void drawRRect(const SkDraw&, const SkRRect& rr,
139 const SkPaint& paint) SK_OVERRIDE;
142 * If pathIsMutable, then the implementation is allowed to cast path to a
143 * non-const pointer and modify it in place (as an optimization). Canvas
144 * may do this to implement helpers such as drawOval, by placing a temp
145 * path on the stack to hold the representation of the oval.
147 * If prePathMatrix is not null, it should logically be applied before any
148 * stroking or other effects. If there are no effects on the paint that
149 * affect the geometry/rasterization, then the pre matrix can just be
150 * pre-concated with the current matrix.
152 virtual void drawPath(const SkDraw&, const SkPath& path,
153 const SkPaint& paint,
154 const SkMatrix* prePathMatrix = NULL,
155 bool pathIsMutable = false) SK_OVERRIDE;
156 virtual void drawBitmap(const SkDraw&, const SkBitmap& bitmap,
157 const SkMatrix& matrix, const SkPaint& paint) SK_OVERRIDE;
158 virtual void drawSprite(const SkDraw&, const SkBitmap& bitmap,
159 int x, int y, const SkPaint& paint) SK_OVERRIDE;
162 * The default impl. will create a bitmap-shader from the bitmap,
163 * and call drawRect with it.
165 virtual void drawBitmapRect(const SkDraw&, const SkBitmap&,
166 const SkRect* srcOrNull, const SkRect& dst,
167 const SkPaint& paint,
168 SkCanvas::DrawBitmapRectFlags flags) SK_OVERRIDE;
171 * Does not handle text decoration.
172 * Decorations (underline and stike-thru) will be handled by SkCanvas.
174 virtual void drawText(const SkDraw&, const void* text, size_t len,
175 SkScalar x, SkScalar y, const SkPaint& paint) SK_OVERRIDE;
176 virtual void drawPosText(const SkDraw&, const void* text, size_t len,
177 const SkScalar pos[], SkScalar constY,
178 int scalarsPerPos, const SkPaint& paint) SK_OVERRIDE;
179 virtual void drawTextOnPath(const SkDraw&, const void* text, size_t len,
180 const SkPath& path, const SkMatrix* matrix,
181 const SkPaint& paint) SK_OVERRIDE;
182 virtual void drawVertices(const SkDraw&, SkCanvas::VertexMode, int vertexCount,
183 const SkPoint verts[], const SkPoint texs[],
184 const SkColor colors[], SkXfermode* xmode,
185 const uint16_t indices[], int indexCount,
186 const SkPaint& paint) SK_OVERRIDE;
187 /** The SkBaseDevice passed will be an SkBaseDevice which was returned by a call to
188 onCreateCompatibleDevice on this device with kSaveLayer_Usage.
190 virtual void drawDevice(const SkDraw&, SkBaseDevice*, int x, int y,
191 const SkPaint&) SK_OVERRIDE;
193 ///////////////////////////////////////////////////////////////////////////
195 /** Update as needed the pixel value in the bitmap, so that the caller can
196 access the pixels directly. Note: only the pixels field should be
197 altered. The config/width/height/rowbytes must remain unchanged.
198 @return the device contents as a bitmap
200 virtual const SkBitmap& onAccessBitmap() SK_OVERRIDE;
202 SkPixelRef* getPixelRef() const { return fBitmap.pixelRef(); }
203 // just for subclasses, to assign a custom pixelref
204 SkPixelRef* setPixelRef(SkPixelRef* pr) {
205 fBitmap.setPixelRef(pr);
210 * Implements readPixels API. The caller will ensure that:
211 * 1. bitmap has pixel config kARGB_8888_Config.
212 * 2. bitmap has pixels.
213 * 3. The rectangle (x, y, x + bitmap->width(), y + bitmap->height()) is
214 * contained in the device bounds.
216 virtual bool onReadPixels(const SkBitmap& bitmap,
218 SkCanvas::Config8888 config8888) SK_OVERRIDE;
220 /** Called when this device is installed into a Canvas. Balanced by a call
221 to unlockPixels() when the device is removed from a Canvas.
223 virtual void lockPixels() SK_OVERRIDE;
224 virtual void unlockPixels() SK_OVERRIDE;
227 * Returns true if the device allows processing of this imagefilter. If
228 * false is returned, then the filter is ignored. This may happen for
229 * some subclasses that do not support pixel manipulations after drawing
230 * has occurred (e.g. printing). The default implementation returns true.
232 virtual bool allowImageFilter(const SkImageFilter*) SK_OVERRIDE;
235 * Override and return true for filters that the device can handle
236 * intrinsically. Doing so means that SkCanvas will pass-through this
237 * filter to drawSprite and drawDevice (and potentially filterImage).
238 * Returning false means the SkCanvas will have apply the filter itself,
239 * and just pass the resulting image to the device.
241 virtual bool canHandleImageFilter(const SkImageFilter*) SK_OVERRIDE;
244 * Related (but not required) to canHandleImageFilter, this method returns
245 * true if the device could apply the filter to the src bitmap and return
246 * the result (and updates offset as needed).
247 * If the device does not recognize or support this filter,
248 * it just returns false and leaves result and offset unchanged.
250 virtual bool filterImage(const SkImageFilter*, const SkBitmap&, const SkMatrix&,
251 SkBitmap* result, SkIPoint* offset) SK_OVERRIDE;
254 friend class SkCanvas;
255 friend struct DeviceCM; //for setMatrixClip
257 friend class SkDrawIter;
258 friend class SkDeviceFilteredPaint;
259 friend class SkDeviceImageFilterProxy;
261 friend class SkSurface_Raster;
263 void init(SkBitmap::Config config, int width, int height, bool isOpaque);
265 // used to change the backend's pixels (and possibly config/rowbytes)
266 // but cannot change the width/height, so there should be no change to
267 // any clip information.
268 virtual void replaceBitmapBackendForRasterSurface(const SkBitmap&) SK_OVERRIDE;
271 * Subclasses should override this to implement createCompatibleDevice.
273 virtual SkBaseDevice* onCreateCompatibleDevice(SkBitmap::Config config,
274 int width, int height,
276 Usage usage) SK_OVERRIDE;
278 /** Causes any deferred drawing to the device to be completed.
280 virtual void flush() SK_OVERRIDE {}
282 virtual SkSurface* newSurface(const SkImageInfo&) SK_OVERRIDE;
283 virtual const void* peekPixels(SkImageInfo*, size_t* rowBytes) SK_OVERRIDE;
287 typedef SkBaseDevice INHERITED;
290 #endif // SkBitmapDevice_DEFINED