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 SkQuadClipper_DEFINED 10 #define SkQuadClipper_DEFINED 11 12 #include "SkPath.h" 13 14 /** This class is initialized with a clip rectangle, and then can be fed quads, 15 which must already be monotonic in Y. 16 17 In the future, it might return a series of segments, allowing it to clip 18 also in X, to ensure that all segments fit in a finite coordinate system. 19 */ 20 class SkQuadClipper { 21 public: 22 SkQuadClipper(); 23 24 void setClip(const SkIRect& clip); 25 26 bool clipQuad(const SkPoint src[3], SkPoint dst[3]); 27 28 private: 29 SkRect fClip; 30 }; 31 32 /** Iterator that returns the clipped segements of a quad clipped to a rect. 33 The segments will be either lines or quads (based on SkPath::Verb), and 34 will all be monotonic in Y 35 */ 36 class SkQuadClipper2 { 37 public: 38 bool clipQuad(const SkPoint pts[3], const SkRect& clip); 39 bool clipCubic(const SkPoint pts[4], const SkRect& clip); 40 41 SkPath::Verb next(SkPoint pts[]); 42 43 private: 44 SkPoint* fCurrPoint; 45 SkPath::Verb* fCurrVerb; 46 47 enum { 48 kMaxVerbs = 13, 49 kMaxPoints = 32 50 }; 51 SkPoint fPoints[kMaxPoints]; 52 SkPath::Verb fVerbs[kMaxVerbs]; 53 54 void clipMonoQuad(const SkPoint srcPts[3], const SkRect& clip); 55 void clipMonoCubic(const SkPoint srcPts[4], const SkRect& clip); 56 void appendVLine(SkScalar x, SkScalar y0, SkScalar y1, bool reverse); 57 void appendQuad(const SkPoint pts[3], bool reverse); 58 void appendCubic(const SkPoint pts[4], bool reverse); 59 }; 60 61 #ifdef SK_DEBUG 62 void sk_assert_monotonic_x(const SkPoint pts[], int count); 63 void sk_assert_monotonic_y(const SkPoint pts[], int count); 64 #else 65 #define sk_assert_monotonic_x(pts, count) 66 #define sk_assert_monotonic_y(pts, count) 67 #endif 68 69 #endif 70
