text: /**************************************************************
   * 
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   * 
   *   http://www.apache.org/licenses/LICENSE-2.0
   * 
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   * 
   *************************************************************/
  
  
  
  // MARKER(update_precomp.py): autogen include statement, do not remove
  #include "precompiled_basegfx.hxx"
  #include <basegfx/vector/b2dvector.hxx>
  #include <basegfx/matrix/b2dhommatrix.hxx>
  #include <basegfx/numeric/ftools.hxx>
  
  namespace basegfx
  {
  	B2DVector& B2DVector::normalize()
  	{
  		double fLen(scalar(*this));
  
  		if(fTools::equalZero(fLen))
  		{
  			mfX = 0.0;
  			mfY = 0.0;
  		}
  		else
  		{
  			const double fOne(1.0);
  
  			if(!fTools::equal(fOne, fLen))
  			{
  				fLen = sqrt(fLen);
  
  				if(!fTools::equalZero(fLen))
  				{
  					mfX /= fLen;
  					mfY /= fLen;
  				}
  			}
  		}
  
  		return *this;
  	}
  
  	B2DVector& B2DVector::operator=( const B2DTuple& rVec ) 
  	{ 
  		mfX = rVec.getX();
  		mfY = rVec.getY(); 
  		return *this; 
  	}
  
  
  	double B2DVector::getLength() const 
  	{ 
          if(fTools::equalZero(mfX))
          {
              return fabs(mfY);
          }
          else if(fTools::equalZero(mfY))
          {
              return fabs(mfX);
          }
  
          return hypot( mfX, mfY ); 
  	}
  
  	double B2DVector::scalar( const B2DVector& rVec ) const 
  	{ 
  		return((mfX * rVec.mfX) + (mfY * rVec.mfY)); 
  	}
  
  	double B2DVector::cross( const B2DVector& rVec ) const 
  	{ 
  		return(mfX * rVec.getY() - mfY * rVec.getX()); 
  	}
  
  	double B2DVector::angle( const B2DVector& rVec ) const
  	{
  		return atan2(mfX * rVec.getY() - mfY * rVec.getX(),
  			mfX * rVec.getX() + mfY * rVec.getY());
  	}
  
  	const B2DVector& B2DVector::getEmptyVector()
  	{
  		return (const B2DVector&) B2DTuple::getEmptyTuple();
  	}
  
  	B2DVector& B2DVector::operator*=( const B2DHomMatrix& rMat )
  	{
  		const double fTempX( rMat.get(0,0)*mfX +
  							rMat.get(0,1)*mfY );
  		const double fTempY( rMat.get(1,0)*mfX +
  							rMat.get(1,1)*mfY );
  		mfX = fTempX;
  		mfY = fTempY;
  
  		return *this;
  	}
  
  	B2DVector& B2DVector::setLength(double fLen)
  	{
  		double fLenNow(scalar(*this));
  
  		if(!fTools::equalZero(fLenNow))
  		{
  			const double fOne(1.0);
  
  			if(!fTools::equal(fOne, fLenNow))
  			{
  				fLen /= sqrt(fLenNow);
  			}
  
  			mfX *= fLen;
  			mfY *= fLen;
  		}
  
  		return *this;
  	}
  
  	bool B2DVector::isNormalized() const
  	{
  		const double fOne(1.0);
  		const double fScalar(scalar(*this));
  
  		return fTools::equal(fOne, fScalar);
  	}
  
  	bool areParallel( const B2DVector& rVecA, const B2DVector& rVecB )
  	{
  		const double fValA(rVecA.getX() * rVecB.getY());
  		const double fValB(rVecA.getY() * rVecB.getX());
  
  		return fTools::equal(fValA, fValB);
  	}
  
  	B2VectorOrientation getOrientation( const B2DVector& rVecA, const B2DVector& rVecB )
  	{ 
  		double fVal(rVecA.getX() * rVecB.getY() - rVecA.getY() * rVecB.getX());
  
  		if(fTools::equalZero(fVal))
  		{
  			return ORIENTATION_NEUTRAL;
  		}
  
  		if(fVal > 0.0)
  		{
  			return ORIENTATION_POSITIVE;
  		}
  		else
  		{
  			return ORIENTATION_NEGATIVE;
  		}
  	}
  
  	B2DVector getPerpendicular( const B2DVector& rNormalizedVec )
  	{
  		B2DVector aPerpendicular(-rNormalizedVec.getY(), rNormalizedVec.getX());
  		return aPerpendicular;
  	}
  
  	B2DVector getNormalizedPerpendicular( const B2DVector& rVec )
  	{
  		B2DVector aPerpendicular(rVec);
  		aPerpendicular.normalize();
  		const double aTemp(-aPerpendicular.getY());
  		aPerpendicular.setY(aPerpendicular.getX());
  		aPerpendicular.setX(aTemp);
  		return aPerpendicular;
  	}
  
  	B2DVector operator*( const B2DHomMatrix& rMat, const B2DVector& rVec )
  	{
  		B2DVector aRes( rVec );
  		return aRes*=rMat;
  	}
  
  	B2VectorContinuity getContinuity(const B2DVector& rBackVector, const B2DVector& rForwardVector )
  	{
  		if(rBackVector.equalZero() || rForwardVector.equalZero())
  		{
  			return CONTINUITY_NONE;
  		}
  
  		if(fTools::equal(rBackVector.getX(), -rForwardVector.getX()) && fTools::equal(rBackVector.getY(), -rForwardVector.getY()))
  		{
  			// same direction and same length -> C2
  			return CONTINUITY_C2;
  		}
  
  		if(areParallel(rBackVector, rForwardVector) && rBackVector.scalar(rForwardVector) < 0.0)
  		{
  			// parallel and opposite direction -> C1
  			return CONTINUITY_C1;
  		}
  
  		return CONTINUITY_NONE;
  	}
  } // end of namespace basegfx
  
  // eof
  