1 /* 2 * Copyright 2015 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #ifndef SkPaintFilterCanvas_DEFINED 9 #define SkPaintFilterCanvas_DEFINED 10 11 #include "SkNWayCanvas.h" 12 #include "SkTLazy.h" 13 14 /** \class SkPaintFilterCanvas 15 16 A utility proxy base class for implementing draw/paint filters. 17 */ 18 class SK_API SkPaintFilterCanvas : public SkNWayCanvas { 19 public: 20 /** 21 * The new SkPaintFilterCanvas is configured for forwarding to the 22 * specified canvas. Also copies the target canvas matrix and clip bounds. 23 */ 24 SkPaintFilterCanvas(SkCanvas* canvas); 25 26 enum Type { 27 kPaint_Type, 28 kPoint_Type, 29 kArc_Type, 30 kBitmap_Type, 31 kRect_Type, 32 kRRect_Type, 33 kDRRect_Type, 34 kOval_Type, 35 kPath_Type, 36 kPicture_Type, 37 kDrawable_Type, 38 kText_Type, 39 kTextBlob_Type, 40 kVertices_Type, 41 kPatch_Type, 42 43 kTypeCount 44 }; 45 46 // Forwarded to the wrapped canvas. getBaseLayerSize()47 SkISize getBaseLayerSize() const override { return proxy()->getBaseLayerSize(); } getGrContext()48 GrContext* getGrContext() override { return proxy()->getGrContext(); } 49 50 protected: 51 /** 52 * Called with the paint that will be used to draw the specified type. 53 * The implementation may modify the paint as they wish (using SkTCopyOnFirstWrite::writable). 54 * 55 * The result bool is used to determine whether the draw op is to be 56 * executed (true) or skipped (false). 57 * 58 * Note: The base implementation calls onFilter() for top-level/explicit paints only. 59 * To also filter encapsulated paints (e.g. SkPicture, SkTextBlob), clients may need to 60 * override the relevant methods (i.e. drawPicture, drawTextBlob). 61 */ 62 virtual bool onFilter(SkTCopyOnFirstWrite<SkPaint>* paint, Type type) const = 0; 63 64 void onDrawPaint(const SkPaint&) override; 65 void onDrawPoints(PointMode, size_t count, const SkPoint pts[], const SkPaint&) override; 66 void onDrawRect(const SkRect&, const SkPaint&) override; 67 void onDrawRRect(const SkRRect&, const SkPaint&) override; 68 void onDrawDRRect(const SkRRect&, const SkRRect&, const SkPaint&) override; 69 void onDrawOval(const SkRect&, const SkPaint&) override; 70 void onDrawArc(const SkRect&, SkScalar, SkScalar, bool, const SkPaint&) override; 71 void onDrawPath(const SkPath&, const SkPaint&) override; 72 void onDrawBitmap(const SkBitmap&, SkScalar left, SkScalar top, const SkPaint*) override; 73 void onDrawBitmapRect(const SkBitmap&, const SkRect* src, const SkRect& dst, const SkPaint*, 74 SrcRectConstraint) override; 75 void onDrawBitmapNine(const SkBitmap&, const SkIRect& center, const SkRect& dst, 76 const SkPaint*) override; 77 void onDrawImage(const SkImage*, SkScalar left, SkScalar top, const SkPaint*) override; 78 void onDrawImageRect(const SkImage*, const SkRect* src, const SkRect& dst, 79 const SkPaint*, SrcRectConstraint) override; 80 void onDrawImageNine(const SkImage*, const SkIRect& center, const SkRect& dst, 81 const SkPaint*) override; 82 void onDrawVerticesObject(const SkVertices*, SkBlendMode, const SkPaint&) override; 83 void onDrawPatch(const SkPoint cubics[12], const SkColor colors[4], 84 const SkPoint texCoords[4], SkBlendMode, 85 const SkPaint& paint) override; 86 void onDrawPicture(const SkPicture*, const SkMatrix*, const SkPaint*) override; 87 void onDrawDrawable(SkDrawable*, const SkMatrix*) override; 88 89 void onDrawText(const void* text, size_t byteLength, SkScalar x, SkScalar y, 90 const SkPaint&) override; 91 void onDrawPosText(const void* text, size_t byteLength, const SkPoint pos[], 92 const SkPaint&) override; 93 void onDrawPosTextH(const void* text, size_t byteLength, const SkScalar xpos[], 94 SkScalar constY, const SkPaint&) override; 95 void onDrawTextOnPath(const void* text, size_t byteLength, const SkPath& path, 96 const SkMatrix* matrix, const SkPaint&) override; 97 void onDrawTextRSXform(const void* text, size_t byteLength, const SkRSXform xform[], 98 const SkRect* cull, const SkPaint& paint) override; 99 void onDrawTextBlob(const SkTextBlob* blob, SkScalar x, SkScalar y, 100 const SkPaint& paint) override; 101 102 // Forwarded to the wrapped canvas. 103 sk_sp<SkSurface> onNewSurface(const SkImageInfo&, const SkSurfaceProps&) override; 104 bool onPeekPixels(SkPixmap* pixmap) override; 105 bool onAccessTopLayerPixels(SkPixmap* pixmap) override; 106 SkImageInfo onImageInfo() const override; 107 bool onGetProps(SkSurfaceProps* props) const override; 108 109 private: 110 class AutoPaintFilter; 111 proxy()112 SkCanvas* proxy() const { SkASSERT(fList.count() == 1); return fList[0]; } 113 114 typedef SkNWayCanvas INHERITED; 115 }; 116 117 #endif 118