| |
| /* |
| * Copyright 2010 The Android Open Source Project |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| |
| #ifndef SkDevice_DEFINED |
| #define SkDevice_DEFINED |
| |
| #include "SkRefCnt.h" |
| #include "SkBitmap.h" |
| #include "SkCanvas.h" |
| #include "SkColor.h" |
| |
| class SkClipStack; |
| class SkDraw; |
| struct SkIRect; |
| class SkMatrix; |
| class SkMetaData; |
| class SkRegion; |
| |
| // This is an opaque class, not interpreted by skia |
| class SkGpuRenderTarget; |
| |
| class SK_API SkDevice : public SkRefCnt { |
| public: |
| /** |
| * Construct a new device with the specified bitmap as its backend. It is |
| * valid for the bitmap to have no pixels associated with it. In that case, |
| * any drawing to this device will have no effect. |
| */ |
| SkDevice(const SkBitmap& bitmap); |
| |
| /** |
| * Create a new raster device and have the pixels be automatically |
| * allocated. The rowBytes of the device will be computed automatically |
| * based on the config and the width. |
| * |
| * @param config The desired config for the pixels. If the request cannot |
| * be met, the closest matching support config will be used. |
| * @param width width (in pixels) of the device |
| * @param height height (in pixels) of the device |
| * @param isOpaque Set to true if it is known that all of the pixels will |
| * be drawn to opaquely. Used as an accelerator when drawing |
| * these pixels to another device. |
| */ |
| SkDevice(SkBitmap::Config config, int width, int height, bool isOpaque = false); |
| |
| virtual ~SkDevice(); |
| |
| /** |
| * Creates a device that is of the same type as this device (e.g. SW-raster, |
| * GPU, or PDF). The backing store for this device is created automatically |
| * (e.g. offscreen pixels or FBO or whatever is appropriate). |
| * |
| * @param width width of the device to create |
| * @param height height of the device to create |
| * @param isOpaque performance hint, set to true if you know that you will |
| * draw into this device such that all of the pixels will |
| * be opaque. |
| */ |
| SkDevice* createCompatibleDevice(SkBitmap::Config config, |
| int width, int height, |
| bool isOpaque); |
| |
| SkMetaData& getMetaData(); |
| |
| enum Capabilities { |
| kGL_Capability = 0x1, //!< mask indicating GL support |
| kVector_Capability = 0x2, //!< mask indicating a vector representation |
| kAll_Capabilities = 0x3 |
| }; |
| virtual uint32_t getDeviceCapabilities() { return 0; } |
| |
| /** Return the width of the device (in pixels). |
| */ |
| virtual int width() const { return fBitmap.width(); } |
| /** Return the height of the device (in pixels). |
| */ |
| virtual int height() const { return fBitmap.height(); } |
| |
| /** |
| * Return the bounds of the device in the coordinate space of the root |
| * canvas. The root device will have its top-left at 0,0, but other devices |
| * such as those associated with saveLayer may have a non-zero origin. |
| */ |
| void getGlobalBounds(SkIRect* bounds) const; |
| |
| /** Returns true if the device's bitmap's config treats every pixels as |
| implicitly opaque. |
| */ |
| bool isOpaque() const { return fBitmap.isOpaque(); } |
| |
| /** Return the bitmap config of the device's pixels |
| */ |
| SkBitmap::Config config() const { return fBitmap.getConfig(); } |
| |
| /** Return the bitmap associated with this device. Call this each time you need |
| to access the bitmap, as it notifies the subclass to perform any flushing |
| etc. before you examine the pixels. |
| @param changePixels set to true if the caller plans to change the pixels |
| @return the device's bitmap |
| */ |
| const SkBitmap& accessBitmap(bool changePixels); |
| |
| /** |
| * DEPRECATED: This will be made protected once WebKit stops using it. |
| * Instead use Canvas' writePixels method. |
| * |
| * Similar to draw sprite, this method will copy the pixels in bitmap onto |
| * the device, with the top/left corner specified by (x, y). The pixel |
| * values in the device are completely replaced: there is no blending. |
| * |
| * Currently if bitmap is backed by a texture this is a no-op. This may be |
| * relaxed in the future. |
| * |
| * If the bitmap has config kARGB_8888_Config then the config8888 param |
| * will determines how the pixel valuess are intepreted. If the bitmap is |
| * not kARGB_8888_Config then this parameter is ignored. |
| */ |
| virtual void writePixels(const SkBitmap& bitmap, int x, int y, |
| SkCanvas::Config8888 config8888 = SkCanvas::kNative_Premul_Config8888); |
| |
| /** |
| * Return the device's associated gpu render target, or NULL. |
| */ |
| virtual SkGpuRenderTarget* accessRenderTarget() { return NULL; } |
| |
| |
| /** |
| * Return the device's origin: its offset in device coordinates from |
| * the default origin in its canvas' matrix/clip |
| */ |
| const SkIPoint& getOrigin() const { return fOrigin; } |
| |
| protected: |
| enum Usage { |
| kGeneral_Usage, |
| kSaveLayer_Usage, // <! internal use only |
| }; |
| |
| struct TextFlags { |
| uint32_t fFlags; // SkPaint::getFlags() |
| SkPaint::Hinting fHinting; |
| }; |
| |
| /** |
| * Device may filter the text flags for drawing text here. If it wants to |
| * make a change to the specified values, it should write them into the |
| * textflags parameter (output) and return true. If the paint is fine as |
| * is, then ignore the textflags parameter and return false. |
| * |
| * The baseclass SkDevice filters based on its depth and blitters. |
| */ |
| virtual bool filterTextFlags(const SkPaint& paint, TextFlags*); |
| |
| /** |
| * Called with the correct matrix and clip before this device is drawn |
| * to using those settings. If your subclass overrides this, be sure to |
| * call through to the base class as well. |
| * |
| * The clipstack is another view of the clip. It records the actual |
| * geometry that went into building the region. It is present for devices |
| * that want to parse it, but is not required: the region is a complete |
| * picture of the current clip. (i.e. if you regionize all of the geometry |
| * in the clipstack, you will arrive at an equivalent region to the one |
| * passed in). |
| */ |
| virtual void setMatrixClip(const SkMatrix&, const SkRegion&, |
| const SkClipStack&); |
| |
| /** Called when this device gains focus (i.e becomes the current device |
| for drawing). |
| */ |
| virtual void gainFocus(SkCanvas*, const SkMatrix&, const SkRegion&, |
| const SkClipStack&) {} |
| |
| /** Clears the entire device to the specified color (including alpha). |
| * Ignores the clip. |
| */ |
| virtual void clear(SkColor color); |
| |
| /** |
| * Deprecated name for clear. |
| */ |
| void eraseColor(SkColor eraseColor) { this->clear(eraseColor); } |
| |
| /** These are called inside the per-device-layer loop for each draw call. |
| When these are called, we have already applied any saveLayer operations, |
| and are handling any looping from the paint, and any effects from the |
| DrawFilter. |
| */ |
| virtual void drawPaint(const SkDraw&, const SkPaint& paint); |
| virtual void drawPoints(const SkDraw&, SkCanvas::PointMode mode, size_t count, |
| const SkPoint[], const SkPaint& paint); |
| virtual void drawRect(const SkDraw&, const SkRect& r, |
| const SkPaint& paint); |
| /** |
| * If pathIsMutable, then the implementation is allowed to cast path to a |
| * non-const pointer and modify it in place (as an optimization). Canvas |
| * may do this to implement helpers such as drawOval, by placing a temp |
| * path on the stack to hold the representation of the oval. |
| * |
| * If prePathMatrix is not null, it should logically be applied before any |
| * stroking or other effects. If there are no effects on the paint that |
| * affect the geometry/rasterization, then the pre matrix can just be |
| * pre-concated with the current matrix. |
| */ |
| virtual void drawPath(const SkDraw&, const SkPath& path, |
| const SkPaint& paint, |
| const SkMatrix* prePathMatrix = NULL, |
| bool pathIsMutable = false); |
| virtual void drawBitmap(const SkDraw&, const SkBitmap& bitmap, |
| const SkIRect* srcRectOrNull, |
| const SkMatrix& matrix, const SkPaint& paint); |
| virtual void drawSprite(const SkDraw&, const SkBitmap& bitmap, |
| int x, int y, const SkPaint& paint); |
| /** |
| * Does not handle text decoration. |
| * Decorations (underline and stike-thru) will be handled by SkCanvas. |
| */ |
| virtual void drawText(const SkDraw&, const void* text, size_t len, |
| SkScalar x, SkScalar y, const SkPaint& paint); |
| virtual void drawPosText(const SkDraw&, const void* text, size_t len, |
| const SkScalar pos[], SkScalar constY, |
| int scalarsPerPos, const SkPaint& paint); |
| virtual void drawTextOnPath(const SkDraw&, const void* text, size_t len, |
| const SkPath& path, const SkMatrix* matrix, |
| const SkPaint& paint); |
| #ifdef SK_BUILD_FOR_ANDROID |
| virtual void drawPosTextOnPath(const SkDraw& draw, const void* text, size_t len, |
| const SkPoint pos[], const SkPaint& paint, |
| const SkPath& path, const SkMatrix* matrix); |
| #endif |
| virtual void drawVertices(const SkDraw&, SkCanvas::VertexMode, int vertexCount, |
| const SkPoint verts[], const SkPoint texs[], |
| const SkColor colors[], SkXfermode* xmode, |
| const uint16_t indices[], int indexCount, |
| const SkPaint& paint); |
| /** The SkDevice passed will be an SkDevice which was returned by a call to |
| onCreateCompatibleDevice on this device with kSaveLayer_Usage. |
| */ |
| virtual void drawDevice(const SkDraw&, SkDevice*, int x, int y, |
| const SkPaint&); |
| |
| /** |
| * On success (returns true), copy the device pixels into the bitmap. |
| * On failure, the bitmap parameter is left unchanged and false is |
| * returned. |
| * |
| * The device's pixels are converted to the bitmap's config. The only |
| * supported config is kARGB_8888_Config, though this is likely to be |
| * relaxed in the future. The meaning of config kARGB_8888_Config is |
| * modified by the enum param config8888. The default value interprets |
| * kARGB_8888_Config as SkPMColor |
| * |
| * If the bitmap has pixels already allocated, the device pixels will be |
| * written there. If not, bitmap->allocPixels() will be called |
| * automatically. If the bitmap is backed by a texture readPixels will |
| * fail. |
| * |
| * The actual pixels written is the intersection of the device's bounds, |
| * and the rectangle formed by the bitmap's width,height and the specified |
| * x,y. If bitmap pixels extend outside of that intersection, they will not |
| * be modified. |
| * |
| * Other failure conditions: |
| * * If the device is not a raster device (e.g. PDF) then readPixels will |
| * fail. |
| * * If bitmap is texture-backed then readPixels will fail. (This may be |
| * relaxed in the future.) |
| */ |
| bool readPixels(SkBitmap* bitmap, |
| int x, int y, |
| SkCanvas::Config8888 config8888); |
| |
| /////////////////////////////////////////////////////////////////////////// |
| |
| /** Update as needed the pixel value in the bitmap, so that the caller can |
| access the pixels directly. Note: only the pixels field should be |
| altered. The config/width/height/rowbytes must remain unchanged. |
| @param bitmap The device's bitmap |
| @return Echo the bitmap parameter, or an alternate (shadow) bitmap |
| maintained by the subclass. |
| */ |
| virtual const SkBitmap& onAccessBitmap(SkBitmap*); |
| |
| SkPixelRef* getPixelRef() const { return fBitmap.pixelRef(); } |
| // just for subclasses, to assign a custom pixelref |
| SkPixelRef* setPixelRef(SkPixelRef* pr, size_t offset) { |
| fBitmap.setPixelRef(pr, offset); |
| return pr; |
| } |
| |
| /** |
| * Implements readPixels API. The caller will ensure that: |
| * 1. bitmap has pixel config kARGB_8888_Config. |
| * 2. bitmap has pixels. |
| * 3. The rectangle (x, y, x + bitmap->width(), y + bitmap->height()) is |
| * contained in the device bounds. |
| */ |
| virtual bool onReadPixels(const SkBitmap& bitmap, |
| int x, int y, |
| SkCanvas::Config8888 config8888); |
| |
| /** Called when this device is installed into a Canvas. Balanaced by a call |
| to unlockPixels() when the device is removed from a Canvas. |
| */ |
| virtual void lockPixels(); |
| virtual void unlockPixels(); |
| |
| /** |
| * Returns true if the device allows processing of this imagefilter. If |
| * false is returned, then the filter is ignored. This may happen for |
| * some subclasses that do not support pixel manipulations after drawing |
| * has occurred (e.g. printing). The default implementation returns true. |
| */ |
| virtual bool allowImageFilter(SkImageFilter*); |
| |
| /** |
| * Override and return true for filters that the device handles |
| * intrinsically. Returning false means call the filter. |
| * Default impl returns false. This will only be called if allowImageFilter() |
| * returned true. |
| */ |
| virtual bool filterImage(SkImageFilter*, const SkBitmap& src, |
| const SkMatrix& ctm, |
| SkBitmap* result, SkIPoint* offset); |
| |
| // This is equal kBGRA_Premul_Config8888 or kRGBA_Premul_Config8888 if |
| // either is identical to kNative_Premul_Config8888. Otherwise, -1. |
| static const SkCanvas::Config8888 kPMColorAlias; |
| |
| private: |
| friend class SkCanvas; |
| friend struct DeviceCM; //for setMatrixClip |
| friend class SkDraw; |
| friend class SkDrawIter; |
| friend class SkDeviceFilteredPaint; |
| friend class DeviceImageFilterProxy; |
| |
| // just called by SkCanvas when built as a layer |
| void setOrigin(int x, int y) { fOrigin.set(x, y); } |
| // just called by SkCanvas for saveLayer |
| SkDevice* createCompatibleDeviceForSaveLayer(SkBitmap::Config config, |
| int width, int height, |
| bool isOpaque); |
| |
| /** |
| * Subclasses should override this to implement createCompatibleDevice. |
| */ |
| virtual SkDevice* onCreateCompatibleDevice(SkBitmap::Config config, |
| int width, int height, |
| bool isOpaque, |
| Usage usage); |
| |
| /** Causes any deferred drawing to the device to be completed. |
| */ |
| virtual void flush() {} |
| |
| SkBitmap fBitmap; |
| SkIPoint fOrigin; |
| SkMetaData* fMetaData; |
| }; |
| |
| #endif |
