1 /* 2 * Copyright (C) 2009 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef SkQuadClipper_DEFINED 18 #define SkQuadClipper_DEFINED 19 20 #include "SkPath.h" 21 22 /** This class is initialized with a clip rectangle, and then can be fed quads, 23 which must already be monotonic in Y. 24 25 In the future, it might return a series of segments, allowing it to clip 26 also in X, to ensure that all segments fit in a finite coordinate system. 27 */ 28 class SkQuadClipper { 29 public: 30 SkQuadClipper(); 31 32 void setClip(const SkIRect& clip); 33 34 bool clipQuad(const SkPoint src[3], SkPoint dst[3]); 35 36 private: 37 SkRect fClip; 38 }; 39 40 /** Iterator that returns the clipped segements of a quad clipped to a rect. 41 The segments will be either lines or quads (based on SkPath::Verb), and 42 will all be monotonic in Y 43 */ 44 class SkQuadClipper2 { 45 public: 46 bool clipQuad(const SkPoint pts[3], const SkRect& clip); 47 bool clipCubic(const SkPoint pts[4], const SkRect& clip); 48 49 SkPath::Verb next(SkPoint pts[]); 50 51 private: 52 SkPoint* fCurrPoint; 53 SkPath::Verb* fCurrVerb; 54 55 enum { 56 kMaxVerbs = 13, 57 kMaxPoints = 32 58 }; 59 SkPoint fPoints[kMaxPoints]; 60 SkPath::Verb fVerbs[kMaxVerbs]; 61 62 void clipMonoQuad(const SkPoint srcPts[3], const SkRect& clip); 63 void clipMonoCubic(const SkPoint srcPts[4], const SkRect& clip); 64 void appendVLine(SkScalar x, SkScalar y0, SkScalar y1, bool reverse); 65 void appendQuad(const SkPoint pts[3], bool reverse); 66 void appendCubic(const SkPoint pts[4], bool reverse); 67 }; 68 69 #ifdef SK_DEBUG 70 void sk_assert_monotonic_x(const SkPoint pts[], int count); 71 void sk_assert_monotonic_y(const SkPoint pts[], int count); 72 #else 73 #define sk_assert_monotonic_x(pts, count) 74 #define sk_assert_monotonic_y(pts, count) 75 #endif 76 77 #endif 78
