1//========================================================================
2//
3// SplashXPathScanner.h
4//
5//========================================================================
6
7//========================================================================
8//
9// Modified under the Poppler project - http://poppler.freedesktop.org
10//
11// All changes made under the Poppler project to this file are licensed
12// under GPL version 2 or later
13//
14// Copyright (C) 2013, 2014, 2021 Thomas Freitag <Thomas.Freitag@alfa.de>
15// Copyright (C) 2018, 2021 Albert Astals Cid <aacid@kde.org>
16// Copyright (C) 2018 Stefan Brüns <stefan.bruens@rwth-aachen.de>
17//
18// To see a description of the changes please see the Changelog file that
19// came with your tarball or type make ChangeLog if you are building from git
20//
21//========================================================================
22
23#ifndef SPLASHXPATHSCANNER_H
24#define SPLASHXPATHSCANNER_H
25
26#include "SplashTypes.h"
27
28#include <poppler-config.h>
29
30#ifdef USE_BOOST_HEADERS
31# include <boost/container/small_vector.hpp>
32#endif
33
34#include <vector>
35
36class SplashXPath;
37class SplashBitmap;
38
39struct SplashIntersect
40{
41 int y;
42 int x0, x1; // intersection of segment with [y, y+1)
43 int count; // EO/NZWN counter increment
44};
45
46//------------------------------------------------------------------------
47// SplashXPathScanner
48//------------------------------------------------------------------------
49
50class SplashXPathScanner
51{
52public:
53 // Create a new SplashXPathScanner object. <xPathA> must be sorted.
54 SplashXPathScanner(const SplashXPath &xPath, bool eoA, int clipYMin, int clipYMax);
55
56 ~SplashXPathScanner();
57
58 SplashXPathScanner(const SplashXPathScanner &) = delete;
59 SplashXPathScanner &operator=(const SplashXPathScanner &) = delete;
60
61 // Return the path's bounding box.
62 void getBBox(int *xMinA, int *yMinA, int *xMaxA, int *yMaxA) const
63 {
64 *xMinA = xMin;
65 *yMinA = yMin;
66 *xMaxA = xMax;
67 *yMaxA = yMax;
68 }
69
70 // Return the path's bounding box.
71 void getBBoxAA(int *xMinA, int *yMinA, int *xMaxA, int *yMaxA) const;
72
73 // Returns true if at least part of the path was outside the
74 // clipYMin/clipYMax bounds passed to the constructor.
75 bool hasPartialClip() const { return partialClip; }
76
77 // Return the min/max x values for the span at <y>.
78 void getSpanBounds(int y, int *spanXMin, int *spanXMax) const;
79
80 // Returns true if (<x>,<y>) is inside the path.
81 bool test(int x, int y) const;
82
83 // Returns true if the entire span ([<x0>,<x1>], <y>) is inside the
84 // path.
85 bool testSpan(int x0, int x1, int y) const;
86
87 // Renders one anti-aliased line into <aaBuf>. Returns the min and
88 // max x coordinates with non-zero pixels in <x0> and <x1>.
89 void renderAALine(SplashBitmap *aaBuf, int *x0, int *x1, int y, bool adjustVertLine = false) const;
90
91 // Clips an anti-aliased line by setting pixels to zero. On entry,
92 // all non-zero pixels are between <x0> and <x1>. This function
93 // will update <x0> and <x1>.
94 void clipAALine(SplashBitmap *aaBuf, int *x0, int *x1, int y) const;
95
96private:
97 void computeIntersections(const SplashXPath &xPath);
98 bool addIntersection(double segYMin, double segYMax, int y, int x0, int x1, int count);
99
100 bool eo;
101 int xMin, yMin, xMax, yMax;
102 bool partialClip;
103
104#ifdef USE_BOOST_HEADERS
105 typedef boost::container::small_vector<SplashIntersect, 4> IntersectionLine;
106#else
107 typedef std::vector<SplashIntersect> IntersectionLine;
108#endif
109 std::vector<IntersectionLine> allIntersections;
110
111 friend class SplashXPathScanIterator;
112};
113
114class SplashXPathScanIterator
115{
116public:
117 SplashXPathScanIterator(const SplashXPathScanner &scanner, int y);
118
119 // Returns the next span inside the path at the current y position
120 // Returns false if there are no more spans.
121 bool getNextSpan(int *x0, int *x1);
122
123private:
124#ifdef USE_BOOST_HEADERS
125 typedef boost::container::small_vector<SplashIntersect, 4> IntersectionLine;
126#else
127 typedef std::vector<SplashIntersect> IntersectionLine;
128#endif
129 const IntersectionLine &line;
130
131 size_t interIdx; // current index into <line>
132 int interCount; // current EO/NZWN counter
133 const bool eo;
134};
135
136#endif
137

source code of poppler/splash/SplashXPathScanner.h