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 SkAutoKern_DEFINED 11#define SkAutoKern_DEFINED 12 13#include "SkGlyph.h" 14 15#define SkAutoKern_AdjustF(prev, next) (((next) - (prev) + 32) >> 6 << 16) 16#define SkAutoKern_AdjustS(prev, next) SkIntToScalar(((next) - (prev) + 32) >> 6) 17 18/* this is a helper class to perform auto-kerning 19 * the adjust() method returns a SkFixed corresponding 20 * to a +1/0/-1 pixel adjustment 21 */ 22 23class SkAutoKern { 24public: 25 SkAutoKern() : fPrevRsbDelta(0) {} 26 27 SkFixed adjust(const SkGlyph& glyph) 28 { 29// if (SkAbs32(glyph.fLsbDelta) > 47 || SkAbs32(glyph.fRsbDelta) > 47) 30// printf("------- %d> L %d R %d\n", glyph.f_GlyphID, glyph.fLsbDelta, glyph.fRsbDelta); 31 32#if 0 33 int distort = fPrevRsbDelta - glyph.fLsbDelta; 34 35 fPrevRsbDelta = glyph.fRsbDelta; 36 37 if (distort >= 32) 38 return -SK_Fixed1; 39 else if (distort < -32) 40 return +SK_Fixed1; 41 else 42 return 0; 43#else 44 SkFixed adjust = SkAutoKern_AdjustF(fPrevRsbDelta, glyph.fLsbDelta); 45 fPrevRsbDelta = glyph.fRsbDelta; 46 return adjust; 47#endif 48 } 49private: 50 int fPrevRsbDelta; 51}; 52 53#endif 54