1 /* 2 * Copyright 2018 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 SkCubicMap_DEFINED 9 #define SkCubicMap_DEFINED 10 11 #include "SkPoint.h" 12 13 /** 14 * Fast evaluation of a cubic ease-in / ease-out curve. This is defined as a parametric cubic 15 * curve inside the unit square. 16 * 17 * pt[0] is implicitly { 0, 0 } 18 * pt[3] is implicitly { 1, 1 } 19 * pts[1,2] are inside the unit square 20 */ 21 class SK_API SkCubicMap { 22 public: 23 SkCubicMap(SkPoint p1, SkPoint p2); 24 25 float computeYFromX(float x) const; 26 27 SkPoint computeFromT(float t) const; 28 29 private: 30 enum Type { 31 kLine_Type, // x == y 32 kCubeRoot_Type, // At^3 == x 33 kSolver_Type, // general monotonic cubic solver 34 }; 35 36 SkPoint fCoeff[3]; 37 Type fType; 38 }; 39 40 #endif 41 42
