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 kText_Type, 38 kTextBlob_Type, 39 kVertices_Type, 40 kPatch_Type, 41 42 kTypeCount 43 }; 44 45 protected: 46 /** 47 * Called with the paint that will be used to draw the specified type. 48 * The implementation may modify the paint as they wish (using SkTCopyOnFirstWrite::writable). 49 * 50 * The result bool is used to determine whether the draw op is to be 51 * executed (true) or skipped (false). 52 * 53 * Note: The base implementation calls onFilter() for top-level/explicit paints only. 54 * To also filter encapsulated paints (e.g. SkPicture, SkTextBlob), clients may need to 55 * override the relevant methods (i.e. drawPicture, drawTextBlob). 56 */ 57 virtual bool onFilter(SkTCopyOnFirstWrite<SkPaint>* paint, Type type) const = 0; 58 59 void onDrawPaint(const SkPaint&) override; 60 void onDrawPoints(PointMode, size_t count, const SkPoint pts[], const SkPaint&) override; 61 void onDrawRect(const SkRect&, const SkPaint&) override; 62 void onDrawRRect(const SkRRect&, const SkPaint&) override; 63 void onDrawDRRect(const SkRRect&, const SkRRect&, const SkPaint&) override; 64 void onDrawOval(const SkRect&, const SkPaint&) override; 65 void onDrawArc(const SkRect&, SkScalar, SkScalar, bool, const SkPaint&) override; 66 void onDrawPath(const SkPath&, const SkPaint&) override; 67 void onDrawBitmap(const SkBitmap&, SkScalar left, SkScalar top, const SkPaint*) override; 68 void onDrawBitmapRect(const SkBitmap&, const SkRect* src, const SkRect& dst, const SkPaint*, 69 SrcRectConstraint) override; 70 void onDrawBitmapNine(const SkBitmap&, const SkIRect& center, const SkRect& dst, 71 const SkPaint*) override; 72 void onDrawImage(const SkImage*, SkScalar left, SkScalar top, const SkPaint*) override; 73 void onDrawImageRect(const SkImage*, const SkRect* src, const SkRect& dst, 74 const SkPaint*, SrcRectConstraint) override; 75 void onDrawImageNine(const SkImage*, const SkIRect& center, const SkRect& dst, 76 const SkPaint*) override; 77 void onDrawVerticesObject(const SkVertices*, SkBlendMode, const SkPaint&) override; 78 void onDrawPatch(const SkPoint cubics[12], const SkColor colors[4], 79 const SkPoint texCoords[4], SkBlendMode, 80 const SkPaint& paint) override; 81 void onDrawPicture(const SkPicture*, const SkMatrix*, const SkPaint*) override; 82 83 void onDrawText(const void* text, size_t byteLength, SkScalar x, SkScalar y, 84 const SkPaint&) override; 85 void onDrawPosText(const void* text, size_t byteLength, const SkPoint pos[], 86 const SkPaint&) override; 87 void onDrawPosTextH(const void* text, size_t byteLength, const SkScalar xpos[], 88 SkScalar constY, const SkPaint&) override; 89 void onDrawTextOnPath(const void* text, size_t byteLength, const SkPath& path, 90 const SkMatrix* matrix, const SkPaint&) override; 91 void onDrawTextRSXform(const void* text, size_t byteLength, const SkRSXform xform[], 92 const SkRect* cull, const SkPaint& paint) override; 93 void onDrawTextBlob(const SkTextBlob* blob, SkScalar x, SkScalar y, 94 const SkPaint& paint) override; 95 96 private: 97 class AutoPaintFilter; 98 99 typedef SkNWayCanvas INHERITED; 100 }; 101 102 #endif 103