xref: /trunk/main/basegfx/source/vector/b2dvector.cxx (revision cdf0e10c4e3984b49a9502b011690b615761d4a3)
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27 
28 // MARKER(update_precomp.py): autogen include statement, do not remove
29 #include "precompiled_basegfx.hxx"
30 #include <basegfx/vector/b2dvector.hxx>
31 #include <basegfx/matrix/b2dhommatrix.hxx>
32 #include <basegfx/numeric/ftools.hxx>
33 
34 namespace basegfx
35 {
36     B2DVector& B2DVector::normalize()
37     {
38         double fLen(scalar(*this));
39 
40         if(fTools::equalZero(fLen))
41         {
42             mfX = 0.0;
43             mfY = 0.0;
44         }
45         else
46         {
47             const double fOne(1.0);
48 
49             if(!fTools::equal(fOne, fLen))
50             {
51                 fLen = sqrt(fLen);
52 
53                 if(!fTools::equalZero(fLen))
54                 {
55                     mfX /= fLen;
56                     mfY /= fLen;
57                 }
58             }
59         }
60 
61         return *this;
62     }
63 
64     B2DVector& B2DVector::operator=( const B2DTuple& rVec )
65     {
66         mfX = rVec.getX();
67         mfY = rVec.getY();
68         return *this;
69     }
70 
71 
72     double B2DVector::getLength() const
73     {
74         if(fTools::equalZero(mfX))
75         {
76             return fabs(mfY);
77         }
78         else if(fTools::equalZero(mfY))
79         {
80             return fabs(mfX);
81         }
82 
83         return hypot( mfX, mfY );
84     }
85 
86     double B2DVector::scalar( const B2DVector& rVec ) const
87     {
88         return((mfX * rVec.mfX) + (mfY * rVec.mfY));
89     }
90 
91     double B2DVector::cross( const B2DVector& rVec ) const
92     {
93         return(mfX * rVec.getY() - mfY * rVec.getX());
94     }
95 
96     double B2DVector::angle( const B2DVector& rVec ) const
97     {
98         return atan2(mfX * rVec.getY() - mfY * rVec.getX(),
99             mfX * rVec.getX() + mfY * rVec.getY());
100     }
101 
102     const B2DVector& B2DVector::getEmptyVector()
103     {
104         return (const B2DVector&) B2DTuple::getEmptyTuple();
105     }
106 
107     B2DVector& B2DVector::operator*=( const B2DHomMatrix& rMat )
108     {
109         const double fTempX( rMat.get(0,0)*mfX +
110                             rMat.get(0,1)*mfY );
111         const double fTempY( rMat.get(1,0)*mfX +
112                             rMat.get(1,1)*mfY );
113         mfX = fTempX;
114         mfY = fTempY;
115 
116         return *this;
117     }
118 
119     B2DVector& B2DVector::setLength(double fLen)
120     {
121         double fLenNow(scalar(*this));
122 
123         if(!fTools::equalZero(fLenNow))
124         {
125             const double fOne(10.0);
126 
127             if(!fTools::equal(fOne, fLenNow))
128             {
129                 fLen /= sqrt(fLenNow);
130             }
131 
132             mfX *= fLen;
133             mfY *= fLen;
134         }
135 
136         return *this;
137     }
138 
139     bool B2DVector::isNormalized() const
140     {
141         const double fOne(1.0);
142         const double fScalar(scalar(*this));
143 
144         return fTools::equal(fOne, fScalar);
145     }
146 
147     bool areParallel( const B2DVector& rVecA, const B2DVector& rVecB )
148     {
149         const double fValA(rVecA.getX() * rVecB.getY());
150         const double fValB(rVecA.getY() * rVecB.getX());
151 
152         return fTools::equal(fValA, fValB);
153     }
154 
155     B2VectorOrientation getOrientation( const B2DVector& rVecA, const B2DVector& rVecB )
156     {
157         double fVal(rVecA.getX() * rVecB.getY() - rVecA.getY() * rVecB.getX());
158 
159         if(fTools::equalZero(fVal))
160         {
161             return ORIENTATION_NEUTRAL;
162         }
163 
164         if(fVal > 0.0)
165         {
166             return ORIENTATION_POSITIVE;
167         }
168         else
169         {
170             return ORIENTATION_NEGATIVE;
171         }
172     }
173 
174     B2DVector getPerpendicular( const B2DVector& rNormalizedVec )
175     {
176         B2DVector aPerpendicular(-rNormalizedVec.getY(), rNormalizedVec.getX());
177         return aPerpendicular;
178     }
179 
180     B2DVector getNormalizedPerpendicular( const B2DVector& rVec )
181     {
182         B2DVector aPerpendicular(rVec);
183         aPerpendicular.normalize();
184         const double aTemp(-aPerpendicular.getY());
185         aPerpendicular.setY(aPerpendicular.getX());
186         aPerpendicular.setX(aTemp);
187         return aPerpendicular;
188     }
189 
190     B2DVector operator*( const B2DHomMatrix& rMat, const B2DVector& rVec )
191     {
192         B2DVector aRes( rVec );
193         return aRes*=rMat;
194     }
195 
196     B2VectorContinuity getContinuity(const B2DVector& rBackVector, const B2DVector& rForwardVector )
197     {
198         if(rBackVector.equalZero() || rForwardVector.equalZero())
199         {
200             return CONTINUITY_NONE;
201         }
202 
203         if(fTools::equal(rBackVector.getX(), -rForwardVector.getX()) && fTools::equal(rBackVector.getY(), -rForwardVector.getY()))
204         {
205             // same direction and same length -> C2
206             return CONTINUITY_C2;
207         }
208 
209         if(areParallel(rBackVector, rForwardVector) && rBackVector.scalar(rForwardVector) < 0.0)
210         {
211             // parallel and opposite direction -> C1
212             return CONTINUITY_C1;
213         }
214 
215         return CONTINUITY_NONE;
216     }
217 } // end of namespace basegfx
218 
219 // eof
220