1 2 /* 3 * Copyright 2006 The Android Open Source Project 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 10 #ifndef SkAvoidXfermode_DEFINED 11 #define SkAvoidXfermode_DEFINED 12 13 #include "SkXfermode.h" 14 15 /** \class SkAvoidXfermode 16 17 This xfermode will draw the src everywhere except on top of the specified 18 color. 19 */ 20 class SkAvoidXfermode : public SkXfermode { 21 public: 22 enum Mode { 23 kAvoidColor_Mode, //!< draw everywhere except on the opColor 24 kTargetColor_Mode //!< draw only on top of the opColor 25 }; 26 27 /** This xfermode draws, or doesn't draw, based on the destination's 28 distance from an op-color. 29 30 There are two modes, and each mode interprets a tolerance value. 31 32 Avoid: In this mode, drawing is allowed only on destination pixels that 33 are different from the op-color. 34 Tolerance near 0: avoid any colors even remotely similar to the op-color 35 Tolerance near 255: avoid only colors nearly identical to the op-color 36 37 Target: In this mode, drawing only occurs on destination pixels that 38 are similar to the op-color 39 Tolerance near 0: draw only on colors that are nearly identical to the op-color 40 Tolerance near 255: draw on any colors even remotely similar to the op-color 41 */ 42 SkAvoidXfermode(SkColor opColor, U8CPU tolerance, Mode mode); 43 44 // overrides from SkXfermode 45 virtual void xfer32(SkPMColor dst[], const SkPMColor src[], int count, 46 const SkAlpha aa[]) SK_OVERRIDE; 47 virtual void xfer16(uint16_t dst[], const SkPMColor src[], int count, 48 const SkAlpha aa[]) SK_OVERRIDE; 49 virtual void xfer4444(uint16_t dst[], const SkPMColor src[], int count, 50 const SkAlpha aa[]) SK_OVERRIDE; 51 virtual void xferA8(SkAlpha dst[], const SkPMColor src[], int count, 52 const SkAlpha aa[]) SK_OVERRIDE; 53 54 // overrides from SkFlattenable 55 virtual Factory getFactory() SK_OVERRIDE; 56 virtual void flatten(SkFlattenableWriteBuffer&) SK_OVERRIDE; 57 58 static SkFlattenable* CreateProc(SkFlattenableReadBuffer& buffer) { 59 return SkNEW_ARGS(SkAvoidXfermode, (buffer)); 60 } 61 62 SK_DECLARE_FLATTENABLE_REGISTRAR() 63 64 protected: 65 SkAvoidXfermode(SkFlattenableReadBuffer&); 66 67 private: 68 SkColor fOpColor; 69 uint32_t fDistMul; // x.14 70 Mode fMode; 71 72 static SkFlattenable* Create(SkFlattenableReadBuffer&); 73 74 typedef SkXfermode INHERITED; 75 }; 76 77 #endif 78
