1//========================================================================
2//
3// SplashClip.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) 2010, 2018, 2021 Albert Astals Cid <aacid@kde.org>
15// Copyright (C) 2013 Thomas Freitag <Thomas.Freitag@alfa.de>
16// Copyright (C) 2019 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 SPLASHCLIP_H
24#define SPLASHCLIP_H
25
26#include "SplashTypes.h"
27
28#include <memory>
29#include <vector>
30
31class SplashPath;
32class SplashXPath;
33class SplashXPathScanner;
34class SplashBitmap;
35
36//------------------------------------------------------------------------
37
38enum SplashClipResult
39{
40 splashClipAllInside,
41 splashClipAllOutside,
42 splashClipPartial
43};
44
45//------------------------------------------------------------------------
46// SplashClip
47//------------------------------------------------------------------------
48
49class SplashClip
50{
51public:
52 // Create a clip, for the given rectangle.
53 SplashClip(SplashCoord x0, SplashCoord y0, SplashCoord x1, SplashCoord y1, bool antialiasA);
54
55 // Copy a clip.
56 SplashClip *copy() const { return new SplashClip(this); }
57
58 ~SplashClip();
59
60 SplashClip(const SplashClip &) = delete;
61 SplashClip &operator=(const SplashClip &) = delete;
62
63 // Reset the clip to a rectangle.
64 void resetToRect(SplashCoord x0, SplashCoord y0, SplashCoord x1, SplashCoord y1);
65
66 // Intersect the clip with a rectangle.
67 SplashError clipToRect(SplashCoord x0, SplashCoord y0, SplashCoord x1, SplashCoord y1);
68
69 // Intersect the clip with <path>.
70 SplashError clipToPath(SplashPath *path, SplashCoord *matrix, SplashCoord flatness, bool eo);
71
72 // Returns true if (<x>,<y>) is inside the clip.
73 bool test(int x, int y)
74 {
75 // check the rectangle
76 if (x < xMinI || x > xMaxI || y < yMinI || y > yMaxI) {
77 return false;
78 }
79
80 // check the paths
81 return testClipPaths(x, y);
82 }
83
84 // Tests a rectangle against the clipping region. Returns one of:
85 // - splashClipAllInside if the entire rectangle is inside the
86 // clipping region, i.e., all pixels in the rectangle are
87 // visible
88 // - splashClipAllOutside if the entire rectangle is outside the
89 // clipping region, i.e., all the pixels in the rectangle are
90 // clipped
91 // - splashClipPartial if the rectangle is part inside and part
92 // outside the clipping region
93 SplashClipResult testRect(int rectXMin, int rectYMin, int rectXMax, int rectYMax);
94
95 // Similar to testRect, but tests a horizontal span.
96 SplashClipResult testSpan(int spanXMin, int spanXMax, int spanY);
97
98 // Clips an anti-aliased line by setting pixels to zero. On entry,
99 // all non-zero pixels are between <x0> and <x1>. This function
100 // will update <x0> and <x1>.
101 void clipAALine(SplashBitmap *aaBuf, int *x0, int *x1, int y, bool adjustVertLine = false);
102
103 // Get the rectangle part of the clip region.
104 SplashCoord getXMin() { return xMin; }
105 SplashCoord getXMax() { return xMax; }
106 SplashCoord getYMin() { return yMin; }
107 SplashCoord getYMax() { return yMax; }
108
109 // Get the rectangle part of the clip region, in integer coordinates.
110 int getXMinI() { return xMinI; }
111 int getXMaxI() { return xMaxI; }
112 int getYMinI() { return yMinI; }
113 int getYMaxI() { return yMaxI; }
114
115 // Get the number of arbitrary paths used by the clip region.
116 int getNumPaths() { return length; }
117
118protected:
119 explicit SplashClip(const SplashClip *clip);
120 void grow(int nPaths);
121 bool testClipPaths(int x, int y);
122
123 bool antialias;
124 SplashCoord xMin, yMin, xMax, yMax;
125 int xMinI, yMinI, xMaxI, yMaxI;
126 unsigned char *flags;
127 std::vector<std::shared_ptr<SplashXPathScanner>> scanners;
128 int length, size;
129};
130
131#endif
132

source code of poppler/splash/SplashClip.h