1 2 /* 3 * Copyright 2013 Google Inc. 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 9 #ifndef SkBitmapDevice_DEFINED 10 #define SkBitmapDevice_DEFINED 11 12 #include "SkDevice.h" 13 14 /////////////////////////////////////////////////////////////////////////////// 15 class SK_API SkBitmapDevice : public SkBaseDevice { 16 public: 17 SK_DECLARE_INST_COUNT(SkBitmapDevice) 18 19 /** 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. 23 */ 24 SkBitmapDevice(const SkBitmap& bitmap); 25 26 /** 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. 30 */ 31 SkBitmapDevice(const SkBitmap& bitmap, const SkDeviceProperties& deviceProperties); 32 33 static SkBitmapDevice* Create(const SkImageInfo&, 34 const SkDeviceProperties* = NULL); 35 36 virtual SkImageInfo imageInfo() const SK_OVERRIDE; 37 38 /** 39 * Return the device's associated gpu render target, or NULL. 40 */ accessRenderTarget()41 virtual GrRenderTarget* accessRenderTarget() SK_OVERRIDE { return NULL; } 42 43 protected: 44 /** 45 * Device may filter the text flags for drawing text here. If it wants to 46 * make a change to the specified values, it should write them into the 47 * textflags parameter (output) and return true. If the paint is fine as 48 * is, then ignore the textflags parameter and return false. 49 * 50 * The baseclass SkDevice filters based on its depth and blitters. 51 */ 52 virtual bool filterTextFlags(const SkPaint& paint, TextFlags*) SK_OVERRIDE; 53 54 /** Clears the entire device to the specified color (including alpha). 55 * Ignores the clip. 56 */ 57 virtual void clear(SkColor color) SK_OVERRIDE; 58 59 /** These are called inside the per-device-layer loop for each draw call. 60 When these are called, we have already applied any saveLayer operations, 61 and are handling any looping from the paint, and any effects from the 62 DrawFilter. 63 */ 64 virtual void drawPaint(const SkDraw&, const SkPaint& paint) SK_OVERRIDE; 65 virtual void drawPoints(const SkDraw&, SkCanvas::PointMode mode, size_t count, 66 const SkPoint[], const SkPaint& paint) SK_OVERRIDE; 67 virtual void drawRect(const SkDraw&, const SkRect& r, 68 const SkPaint& paint) SK_OVERRIDE; 69 virtual void drawOval(const SkDraw&, const SkRect& oval, 70 const SkPaint& paint) SK_OVERRIDE; 71 virtual void drawRRect(const SkDraw&, const SkRRect& rr, 72 const SkPaint& paint) SK_OVERRIDE; 73 74 /** 75 * If pathIsMutable, then the implementation is allowed to cast path to a 76 * non-const pointer and modify it in place (as an optimization). Canvas 77 * may do this to implement helpers such as drawOval, by placing a temp 78 * path on the stack to hold the representation of the oval. 79 * 80 * If prePathMatrix is not null, it should logically be applied before any 81 * stroking or other effects. If there are no effects on the paint that 82 * affect the geometry/rasterization, then the pre matrix can just be 83 * pre-concated with the current matrix. 84 */ 85 virtual void drawPath(const SkDraw&, const SkPath& path, 86 const SkPaint& paint, 87 const SkMatrix* prePathMatrix = NULL, 88 bool pathIsMutable = false) SK_OVERRIDE; 89 virtual void drawBitmap(const SkDraw&, const SkBitmap& bitmap, 90 const SkMatrix& matrix, const SkPaint& paint) SK_OVERRIDE; 91 virtual void drawSprite(const SkDraw&, const SkBitmap& bitmap, 92 int x, int y, const SkPaint& paint) SK_OVERRIDE; 93 94 /** 95 * The default impl. will create a bitmap-shader from the bitmap, 96 * and call drawRect with it. 97 */ 98 virtual void drawBitmapRect(const SkDraw&, const SkBitmap&, 99 const SkRect* srcOrNull, const SkRect& dst, 100 const SkPaint& paint, 101 SkCanvas::DrawBitmapRectFlags flags) SK_OVERRIDE; 102 103 /** 104 * Does not handle text decoration. 105 * Decorations (underline and stike-thru) will be handled by SkCanvas. 106 */ 107 virtual void drawText(const SkDraw&, const void* text, size_t len, 108 SkScalar x, SkScalar y, const SkPaint& paint) SK_OVERRIDE; 109 virtual void drawPosText(const SkDraw&, const void* text, size_t len, 110 const SkScalar pos[], SkScalar constY, 111 int scalarsPerPos, const SkPaint& paint) SK_OVERRIDE; 112 virtual void drawTextOnPath(const SkDraw&, const void* text, size_t len, 113 const SkPath& path, const SkMatrix* matrix, 114 const SkPaint& paint) SK_OVERRIDE; 115 virtual void drawVertices(const SkDraw&, SkCanvas::VertexMode, int vertexCount, 116 const SkPoint verts[], const SkPoint texs[], 117 const SkColor colors[], SkXfermode* xmode, 118 const uint16_t indices[], int indexCount, 119 const SkPaint& paint) SK_OVERRIDE; 120 /** The SkBaseDevice passed will be an SkBaseDevice which was returned by a call to 121 onCreateDevice on this device with kSaveLayer_Usage. 122 */ 123 virtual void drawDevice(const SkDraw&, SkBaseDevice*, int x, int y, 124 const SkPaint&) SK_OVERRIDE; 125 126 /////////////////////////////////////////////////////////////////////////// 127 128 /** Update as needed the pixel value in the bitmap, so that the caller can 129 access the pixels directly. Note: only the pixels field should be 130 altered. The config/width/height/rowbytes must remain unchanged. 131 @return the device contents as a bitmap 132 */ 133 virtual const SkBitmap& onAccessBitmap() SK_OVERRIDE; 134 getPixelRef()135 SkPixelRef* getPixelRef() const { return fBitmap.pixelRef(); } 136 // just for subclasses, to assign a custom pixelref setPixelRef(SkPixelRef * pr)137 SkPixelRef* setPixelRef(SkPixelRef* pr) { 138 fBitmap.setPixelRef(pr); 139 return pr; 140 } 141 142 virtual bool onReadPixels(const SkImageInfo&, void*, size_t, int x, int y) SK_OVERRIDE; 143 virtual bool onWritePixels(const SkImageInfo&, const void*, size_t, int, int) SK_OVERRIDE; 144 virtual void* onAccessPixels(SkImageInfo* info, size_t* rowBytes) SK_OVERRIDE; 145 146 /** Called when this device is installed into a Canvas. Balanced by a call 147 to unlockPixels() when the device is removed from a Canvas. 148 */ 149 virtual void lockPixels() SK_OVERRIDE; 150 virtual void unlockPixels() SK_OVERRIDE; 151 152 /** 153 * Returns true if the device allows processing of this imagefilter. If 154 * false is returned, then the filter is ignored. This may happen for 155 * some subclasses that do not support pixel manipulations after drawing 156 * has occurred (e.g. printing). The default implementation returns true. 157 */ 158 virtual bool allowImageFilter(const SkImageFilter*) SK_OVERRIDE; 159 160 /** 161 * Override and return true for filters that the device can handle 162 * intrinsically. Doing so means that SkCanvas will pass-through this 163 * filter to drawSprite and drawDevice (and potentially filterImage). 164 * Returning false means the SkCanvas will have apply the filter itself, 165 * and just pass the resulting image to the device. 166 */ 167 virtual bool canHandleImageFilter(const SkImageFilter*) SK_OVERRIDE; 168 169 /** 170 * Related (but not required) to canHandleImageFilter, this method returns 171 * true if the device could apply the filter to the src bitmap and return 172 * the result (and updates offset as needed). 173 * If the device does not recognize or support this filter, 174 * it just returns false and leaves result and offset unchanged. 175 */ 176 virtual bool filterImage(const SkImageFilter*, const SkBitmap&, const SkImageFilter::Context&, 177 SkBitmap* result, SkIPoint* offset) SK_OVERRIDE; 178 179 private: 180 friend class SkCanvas; 181 friend struct DeviceCM; //for setMatrixClip 182 friend class SkDraw; 183 friend class SkDrawIter; 184 friend class SkDeviceFilteredPaint; 185 friend class SkDeviceImageFilterProxy; 186 187 friend class SkSurface_Raster; 188 189 // used to change the backend's pixels (and possibly config/rowbytes) 190 // but cannot change the width/height, so there should be no change to 191 // any clip information. 192 virtual void replaceBitmapBackendForRasterSurface(const SkBitmap&) SK_OVERRIDE; 193 194 virtual SkBaseDevice* onCreateDevice(const SkImageInfo&, Usage) SK_OVERRIDE; 195 196 /** Causes any deferred drawing to the device to be completed. 197 */ flush()198 virtual void flush() SK_OVERRIDE {} 199 200 virtual SkSurface* newSurface(const SkImageInfo&) SK_OVERRIDE; 201 virtual const void* peekPixels(SkImageInfo*, size_t* rowBytes) SK_OVERRIDE; 202 203 SkBitmap fBitmap; 204 205 typedef SkBaseDevice INHERITED; 206 }; 207 208 #endif // SkBitmapDevice_DEFINED 209