AOO410/main/basegfx/source/vector/b2dvector.cxx

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 * to you under the Apache License, Version 2.0 (the
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// 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