Line data Source code
1 : /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
2 : /*
3 : * This file is part of the LibreOffice project.
4 : *
5 : * This Source Code Form is subject to the terms of the Mozilla Public
6 : * License, v. 2.0. If a copy of the MPL was not distributed with this
7 : * file, You can obtain one at http://mozilla.org/MPL/2.0/.
8 : *
9 : * This file incorporates work covered by the following license notice:
10 : *
11 : * Licensed to the Apache Software Foundation (ASF) under one or more
12 : * contributor license agreements. See the NOTICE file distributed
13 : * with this work for additional information regarding copyright
14 : * ownership. The ASF licenses this file to you under the Apache
15 : * License, Version 2.0 (the "License"); you may not use this file
16 : * except in compliance with the License. You may obtain a copy of
17 : * the License at http://www.apache.org/licenses/LICENSE-2.0 .
18 : */
19 :
20 : #include <tools/link.hxx>
21 : #include <tools/line.hxx>
22 : #include <tools/debug.hxx>
23 : #include <tools/helpers.hxx>
24 :
25 : #include <cstdlib>
26 : #include <math.h>
27 :
28 0 : double Line::GetLength() const
29 : {
30 0 : return hypot( maStart.X() - maEnd.X(), maStart.Y() - maEnd.Y() );
31 : }
32 :
33 0 : sal_Bool Line::Intersection( const Line& rLine, Point& rIntersection ) const
34 : {
35 : double fX, fY;
36 : sal_Bool bRet;
37 :
38 0 : if( Intersection( rLine, fX, fY ) )
39 : {
40 0 : rIntersection.X() = FRound( fX );
41 0 : rIntersection.Y() = FRound( fY );
42 0 : bRet = sal_True;
43 : }
44 : else
45 0 : bRet = sal_False;
46 :
47 0 : return bRet;
48 : }
49 :
50 0 : sal_Bool Line::Intersection( const Line& rLine, double& rIntersectionX, double& rIntersectionY ) const
51 : {
52 0 : const double fAx = maEnd.X() - maStart.X();
53 0 : const double fAy = maEnd.Y() - maStart.Y();
54 0 : const double fBx = rLine.maStart.X() - rLine.maEnd.X();
55 0 : const double fBy = rLine.maStart.Y() - rLine.maEnd.Y();
56 0 : const double fDen = fAy * fBx - fAx * fBy;
57 0 : sal_Bool bOk = sal_False;
58 :
59 0 : if( fDen != 0. )
60 : {
61 0 : const double fCx = maStart.X() - rLine.maStart.X();
62 0 : const double fCy = maStart.Y() - rLine.maStart.Y();
63 0 : const double fA = fBy * fCx - fBx * fCy;
64 0 : const sal_Bool bGreater = ( fDen > 0. );
65 :
66 0 : bOk = sal_True;
67 :
68 0 : if ( bGreater )
69 : {
70 0 : if ( ( fA < 0. ) || ( fA > fDen ) )
71 0 : bOk = sal_False;
72 : }
73 0 : else if ( ( fA > 0. ) || ( fA < fDen ) )
74 0 : bOk = sal_False;
75 :
76 0 : if ( bOk )
77 : {
78 0 : const double fB = fAx * fCy - fAy * fCx;
79 :
80 0 : if ( bGreater )
81 : {
82 0 : if ( ( fB < 0. ) || ( fB > fDen ) )
83 0 : bOk = sal_False;
84 : }
85 0 : else if ( ( fB > 0. ) || ( fB < fDen ) )
86 0 : bOk = sal_False;
87 :
88 0 : if( bOk )
89 : {
90 0 : const double fAlpha = fA / fDen;
91 :
92 0 : rIntersectionX = ( maStart.X() + fAlpha * fAx );
93 0 : rIntersectionY = ( maStart.Y() + fAlpha * fAy );
94 : }
95 : }
96 : }
97 :
98 0 : return bOk;
99 : }
100 :
101 0 : sal_Bool Line::Intersection( const Rectangle& rRect, Line& rIntersection ) const
102 : {
103 0 : const sal_Bool bStartInside = rRect.IsInside( maStart );
104 0 : const sal_Bool bEndInside = rRect.IsInside( maEnd );
105 0 : sal_Bool bRet = sal_True;
106 :
107 0 : if( bStartInside && bEndInside )
108 : {
109 : // line completely inside rect
110 0 : rIntersection.maStart = maStart;
111 0 : rIntersection.maEnd = maEnd;
112 : }
113 : else
114 : {
115 : // calculate intersections
116 0 : const Point aTL( rRect.TopLeft() ), aTR( rRect.TopRight() );
117 0 : const Point aBR( rRect.BottomRight() ), aBL( rRect.BottomLeft() );
118 0 : Point aIntersect1, aIntersect2;
119 0 : Point* pCurIntersection = &aIntersect1;
120 :
121 0 : if( Intersection( Line( aTL, aTR ), *pCurIntersection ) )
122 0 : pCurIntersection = &aIntersect2;
123 :
124 0 : if( Intersection( Line( aTR, aBR ), *pCurIntersection ) )
125 0 : pCurIntersection = ( pCurIntersection == &aIntersect1 ) ? &aIntersect2 : NULL;
126 :
127 0 : if( pCurIntersection && Intersection( Line( aBR, aBL ), *pCurIntersection ) )
128 0 : pCurIntersection = ( pCurIntersection == &aIntersect1 ) ? &aIntersect2 : NULL;
129 :
130 0 : if( pCurIntersection && Intersection( Line( aBL, aTL ), *pCurIntersection ) )
131 0 : pCurIntersection = ( pCurIntersection == &aIntersect1 ) ? &aIntersect2 : NULL;
132 :
133 0 : if( !pCurIntersection )
134 : {
135 : // two intersections
136 0 : rIntersection.maStart = aIntersect1;
137 0 : rIntersection.maEnd = aIntersect2;
138 : }
139 0 : else if( pCurIntersection == &aIntersect2 )
140 : {
141 : // one intersection
142 0 : rIntersection.maStart = aIntersect1;
143 :
144 0 : if( ( maStart != aIntersect1 ) && bStartInside )
145 0 : rIntersection.maEnd = maStart;
146 0 : else if( ( maEnd != aIntersect1 ) && bEndInside )
147 0 : rIntersection.maEnd = maEnd;
148 : else
149 0 : rIntersection.maEnd = rIntersection.maStart;
150 : }
151 : else
152 0 : bRet = sal_False;
153 : }
154 :
155 0 : return bRet;
156 : }
157 :
158 0 : double Line::GetDistance( const double& rPtX, const double& rPtY ) const
159 : {
160 : double fDist;
161 :
162 0 : if( maStart != maEnd )
163 : {
164 0 : const double fDistX = maEnd.X() - maStart.X();
165 0 : const double fDistY = maEnd.Y() - maStart.Y();
166 0 : const double fACX = maStart.X() - rPtX;
167 0 : const double fACY = maStart.Y() - rPtY;
168 0 : const double fL2 = fDistX * fDistX + fDistY * fDistY;
169 0 : const double fR = ( fACY * -fDistY - fACX * fDistX ) / fL2;
170 0 : const double fS = ( fACY * fDistX - fACX * fDistY ) / fL2;
171 :
172 0 : if( fR < 0.0 )
173 : {
174 0 : fDist = hypot( maStart.X() - rPtX, maStart.Y() - rPtY );
175 :
176 0 : if( fS < 0.0 )
177 0 : fDist *= -1.0;
178 : }
179 0 : else if( fR <= 1.0 )
180 0 : fDist = fS * sqrt( fL2 );
181 : else
182 : {
183 0 : fDist = hypot( maEnd.X() - rPtX, maEnd.Y() - rPtY );
184 :
185 0 : if( fS < 0.0 )
186 0 : fDist *= -1.0;
187 : }
188 : }
189 : else
190 0 : fDist = hypot( maStart.X() - rPtX, maStart.Y() - rPtY );
191 :
192 0 : return fDist;
193 : }
194 :
195 : /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
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