1 /* 2 * Copyright 2011 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 SkArithmeticMode_DEFINED 9 #define SkArithmeticMode_DEFINED 10 11 #include "SkXfermode.h" 12 13 class SkArithmeticMode : public SkXfermode { 14 public: 15 /** 16 * result = clamp[k1 * src * dst + k2 * src + k3 * dst + k4] 17 * 18 * src and dst are treated as being [0.0 .. 1.0]. The polynomial is 19 * evaluated on their unpremultiplied components. 20 * 21 * k1=k2=k3=0, k4=1.0 results in returning opaque white 22 * k1=k3=k4=0, k2=1.0 results in returning the src 23 * k1=k2=k4=0, k3=1.0 results in returning the dst 24 */ 25 static SkXfermode* Create(SkScalar k1, SkScalar k2, 26 SkScalar k3, SkScalar k4); 27 }; 28 29 #endif 30 31
