1 2 /* 3 * Copyright 2011 Google Inc. 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 SkClampRange_DEFINED 11 #define SkClampRange_DEFINED 12 13 #include "SkFixed.h" 14 15 /** 16 * Iteration fixed fx by dx, clamping as you go to [0..0xFFFF], this class 17 * computes the (up to) 3 spans there are: 18 * 19 * range0: use constant value V0 20 * range1: iterate as usual fx += dx 21 * range2: use constant value V1 22 */ 23 struct SkClampRange { 24 int fCount0; // count for fV0 25 int fCount1; // count for interpolating (fV0...fV1) 26 int fCount2; // count for fV1 27 SkFixed fFx1; // initial fx value for the fCount1 range. 28 // only valid if fCount1 > 0 29 int fV0, fV1; 30 bool fOverflowed; // true if we had to clamp due to numerical overflow 31 32 void init(SkFixed fx, SkFixed dx, int count, int v0, int v1); 33 34 private: 35 void initFor1(SkFixed fx); 36 }; 37 38 #endif 39 40