1 /* 2 * Copyright 2009 The Android Open Source Project 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 9 #ifndef SkEdgeClipper_DEFINED 10 #define SkEdgeClipper_DEFINED 11 12 #include "SkPath.h" 13 14 /** This is basically an iterator. It is initialized with an edge and a clip, 15 and then next() is called until it returns kDone_Verb. 16 */ 17 class SkEdgeClipper { 18 public: 19 SkEdgeClipper(bool canCullToTheRight) : fCanCullToTheRight(canCullToTheRight) {} 20 21 bool clipLine(SkPoint p0, SkPoint p1, const SkRect& clip); 22 bool clipQuad(const SkPoint pts[3], const SkRect& clip); 23 bool clipCubic(const SkPoint pts[4], const SkRect& clip); 24 25 SkPath::Verb next(SkPoint pts[]); 26 27 bool canCullToTheRight() const { return fCanCullToTheRight; } 28 29 private: 30 SkPoint* fCurrPoint; 31 SkPath::Verb* fCurrVerb; 32 const bool fCanCullToTheRight; 33 34 enum { 35 kMaxVerbs = 18, // max curvature in X and Y split cubic into 9 pieces, * (line + cubic) 36 kMaxPoints = 54 // 2 lines + 1 cubic require 6 points; times 9 pieces 37 }; 38 SkPoint fPoints[kMaxPoints]; 39 SkPath::Verb fVerbs[kMaxVerbs]; 40 41 void clipMonoQuad(const SkPoint srcPts[3], const SkRect& clip); 42 void clipMonoCubic(const SkPoint srcPts[4], const SkRect& clip); 43 void appendLine(SkPoint p0, SkPoint p1); 44 void appendVLine(SkScalar x, SkScalar y0, SkScalar y1, bool reverse); 45 void appendQuad(const SkPoint pts[3], bool reverse); 46 void appendCubic(const SkPoint pts[4], bool reverse); 47 }; 48 49 #ifdef SK_DEBUG 50 void sk_assert_monotonic_x(const SkPoint pts[], int count); 51 void sk_assert_monotonic_y(const SkPoint pts[], int count); 52 #else 53 #define sk_assert_monotonic_x(pts, count) 54 #define sk_assert_monotonic_y(pts, count) 55 #endif 56 57 #endif 58
