office-gobmx/basegfx/source/matrix/b2dhommatrix.cxx

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// MARKER(update_precomp.py): autogen include statement, do not remove
#include "precompiled_basegfx.hxx"
#include <osl/diagnose.h>
#include <rtl/instance.hxx>
#include <basegfx/matrix/b2dhommatrix.hxx>
#include <hommatrixtemplate.hxx>
#include <basegfx/tuple/b2dtuple.hxx>
#include <basegfx/vector/b2dvector.hxx>

namespace basegfx
{
    class Impl2DHomMatrix : public ::basegfx::internal::ImplHomMatrixTemplate< 3 >
    {
    };

    namespace { struct IdentityMatrix : public rtl::Static< B2DHomMatrix::ImplType,
                                                            IdentityMatrix > {}; }

    B2DHomMatrix::B2DHomMatrix() :
        mpImpl( IdentityMatrix::get() ) // use common identity matrix
    {
    }

    B2DHomMatrix::B2DHomMatrix(const B2DHomMatrix& rMat) :
        mpImpl(rMat.mpImpl)
    {
    }

    B2DHomMatrix::~B2DHomMatrix()
    {
    }

    B2DHomMatrix& B2DHomMatrix::operator=(const B2DHomMatrix& rMat)
    {
        mpImpl = rMat.mpImpl;
        return *this;
    }

    void B2DHomMatrix::makeUnique()
    {
        mpImpl.make_unique();
    }

    double B2DHomMatrix::get(sal_uInt16 nRow, sal_uInt16 nColumn) const
    {
        return mpImpl->get(nRow, nColumn);
    }

    void B2DHomMatrix::set(sal_uInt16 nRow, sal_uInt16 nColumn, double fValue)
    {
        mpImpl->set(nRow, nColumn, fValue);
    }

    bool B2DHomMatrix::isLastLineDefault() const
    {
        return mpImpl->isLastLineDefault();
    }

    bool B2DHomMatrix::isIdentity() const
    {
        if(mpImpl.same_object(IdentityMatrix::get()))
            return true;

        return mpImpl->isIdentity();
    }

    void B2DHomMatrix::identity()
    {
        mpImpl = IdentityMatrix::get();
    }

    bool B2DHomMatrix::isInvertible() const
    {
        return mpImpl->isInvertible();
    }

    bool B2DHomMatrix::invert()
    {
        Impl2DHomMatrix aWork(*mpImpl);
        sal_uInt16* pIndex = new sal_uInt16[mpImpl->getEdgeLength()];
        sal_Int16 nParity;

        if(aWork.ludcmp(pIndex, nParity))
        {
            mpImpl->doInvert(aWork, pIndex);
            delete[] pIndex;

            return true;
        }

        delete[] pIndex;
        return false;
    }

    bool B2DHomMatrix::isNormalized() const
    {
        return mpImpl->isNormalized();
    }

    void B2DHomMatrix::normalize()
    {
        if(!const_cast<const B2DHomMatrix*>(this)->mpImpl->isNormalized())
            mpImpl->doNormalize();
    }

    double B2DHomMatrix::determinant() const
    {
        return mpImpl->doDeterminant();
    }

    double B2DHomMatrix::trace() const
    {
        return mpImpl->doTrace();
    }

    void B2DHomMatrix::transpose()
    {
        mpImpl->doTranspose();
    }

    B2DHomMatrix& B2DHomMatrix::operator+=(const B2DHomMatrix& rMat)
    {
        mpImpl->doAddMatrix(*rMat.mpImpl);
        return *this;
    }

    B2DHomMatrix& B2DHomMatrix::operator-=(const B2DHomMatrix& rMat)
    {
        mpImpl->doSubMatrix(*rMat.mpImpl);
        return *this;
    }

    B2DHomMatrix& B2DHomMatrix::operator*=(double fValue)
    {
        const double fOne(1.0);

        if(!fTools::equal(fOne, fValue))
            mpImpl->doMulMatrix(fValue);

        return *this;
    }

    B2DHomMatrix& B2DHomMatrix::operator/=(double fValue)
    {
        const double fOne(1.0);

        if(!fTools::equal(fOne, fValue))
            mpImpl->doMulMatrix(1.0 / fValue);

        return *this;
    }

    B2DHomMatrix& B2DHomMatrix::operator*=(const B2DHomMatrix& rMat)
    {
        if(!rMat.isIdentity())
            mpImpl->doMulMatrix(*rMat.mpImpl);

        return *this;
    }

    bool B2DHomMatrix::operator==(const B2DHomMatrix& rMat) const
    {
        if(mpImpl.same_object(rMat.mpImpl))
            return true;

        return mpImpl->isEqual(*rMat.mpImpl);
    }

    bool B2DHomMatrix::operator!=(const B2DHomMatrix& rMat) const
    {
        return !(*this == rMat);
    }

    void B2DHomMatrix::rotate(double fRadiant)
    {
        if(!fTools::equalZero(fRadiant))
        {
            double fSin(0.0);
            double fCos(0.0);

            // is the rotation angle an approximate multiple of pi/2?
            // If yes, force fSin/fCos to -1/0/1, to maintain
            // orthogonality (which might also be advantageous for the
            // other cases, but: for multiples of pi/2, the exact
            // values _can_ be attained. It would be largely
            // unintuitive, if a 180 degrees rotation would introduce
            // slight roundoff errors, instead of exactly mirroring
            // the coordinate system).
            if( fTools::equalZero( fmod( fRadiant, F_PI2 ) ) )
            {
                // determine quadrant
                const sal_Int32 nQuad(
                    (4 + fround( 4/F_2PI*fmod( fRadiant, F_2PI ) )) % 4 );
                switch( nQuad )
                {
                    case 0: // -2pi,0,2pi
                        fSin = 0.0;
                        fCos = 1.0;
                        break;

                    case 1: // -3/2pi,1/2pi
                        fSin = 1.0;
                        fCos = 0.0;
                        break;

                    case 2: // -pi,pi
                        fSin = 0.0;
                        fCos = -1.0;
                        break;

                    case 3: // -1/2pi,3/2pi
                        fSin = -1.0;
                        fCos = 0.0;
                        break;

                    default:
                        OSL_ENSURE( false,
                                    "B2DHomMatrix::rotate(): Impossible case reached" );
                }
            }
            else
            {
                // TODO(P1): Maybe use glibc's sincos here (though
                // that's kinda non-portable...)
                fSin = sin(fRadiant);
                fCos = cos(fRadiant);
            }

            Impl2DHomMatrix aRotMat;

            aRotMat.set(0, 0, fCos);
            aRotMat.set(1, 1, fCos);
            aRotMat.set(1, 0, fSin);
            aRotMat.set(0, 1, -fSin);

            mpImpl->doMulMatrix(aRotMat);
        }
    }

    void B2DHomMatrix::translate(double fX, double fY)
    {
        if(!fTools::equalZero(fX) || !fTools::equalZero(fY))
        {
            Impl2DHomMatrix aTransMat;

            aTransMat.set(0, 2, fX);
            aTransMat.set(1, 2, fY);

            mpImpl->doMulMatrix(aTransMat);
        }
    }

    void B2DHomMatrix::scale(double fX, double fY)
    {
        const double fOne(1.0);

        if(!fTools::equal(fOne, fX) || !fTools::equal(fOne, fY))
        {
            Impl2DHomMatrix aScaleMat;

            aScaleMat.set(0, 0, fX);
            aScaleMat.set(1, 1, fY);

            mpImpl->doMulMatrix(aScaleMat);
        }
    }

    void B2DHomMatrix::shearX(double fSx)
    {
        // #i76239# do not test againt 1.0, but against 0.0. We are talking about a value not on the diagonal (!)
        if(!fTools::equalZero(fSx))
        {
            Impl2DHomMatrix aShearXMat;

            aShearXMat.set(0, 1, fSx);

            mpImpl->doMulMatrix(aShearXMat);
        }
    }

    void B2DHomMatrix::shearY(double fSy)
    {
        // #i76239# do not test againt 1.0, but against 0.0. We are talking about a value not on the diagonal (!)
        if(!fTools::equalZero(fSy))
        {
            Impl2DHomMatrix aShearYMat;

            aShearYMat.set(1, 0, fSy);

            mpImpl->doMulMatrix(aShearYMat);
        }
    }

    /** Decomposition

       New, optimized version with local shearX detection. Old version (keeping
       below, is working well, too) used the 3D matrix decomposition when
       shear was used. Keeping old version as comment below since it may get
       necessary to add the determinant() test from there here, too.
    */
    bool B2DHomMatrix::decompose(B2DTuple& rScale, B2DTuple& rTranslate, double& rRotate, double& rShearX) const
    {
        // when perspective is used, decompose is not made here
        if(!mpImpl->isLastLineDefault())
        {
            return false;
        }

        // reset rotate and shear and copy translation values in every case
        rRotate = rShearX = 0.0;
        rTranslate.setX(get(0, 2));
        rTranslate.setY(get(1, 2));

        // test for rotation and shear
        if(fTools::equalZero(get(0, 1)) && fTools::equalZero(get(1, 0)))
        {
            // no rotation and shear, copy scale values
            rScale.setX(get(0, 0));
            rScale.setY(get(1, 1));
        }
        else
        {
            // get the unit vectors of the transformation -> the perpendicular vectors
            B2DVector aUnitVecX(get(0, 0), get(1, 0));
            B2DVector aUnitVecY(get(0, 1), get(1, 1));
            const double fScalarXY(aUnitVecX.scalar(aUnitVecY));

            // Test if shear is zero. That's the case if the unit vectors in the matrix
            // are perpendicular -> scalar is zero. This is also the case when one of
            // the unit vectors is zero.
            if(fTools::equalZero(fScalarXY))
            {
                // calculate unsigned scale values
                rScale.setX(aUnitVecX.getLength());
                rScale.setY(aUnitVecY.getLength());

                // check unit vectors for zero lengths
                const bool bXIsZero(fTools::equalZero(rScale.getX()));
                const bool bYIsZero(fTools::equalZero(rScale.getY()));

                if(bXIsZero || bYIsZero)
                {
                    // still extract as much as possible. Scalings are already set
                    if(!bXIsZero)
                    {
                        // get rotation of X-Axis
                        rRotate = atan2(aUnitVecX.getY(), aUnitVecX.getX());
                    }
                    else if(!bYIsZero)
                    {
                        // get rotation of X-Axis. When assuming X and Y perpendicular
                        // and correct rotation, it's the Y-Axis rotation minus 90 degrees
                        rRotate = atan2(aUnitVecY.getY(), aUnitVecY.getX()) - M_PI_2;
                    }

                    // one or both unit vectors do not extist, determinant is zero, no decomposition possible.
                    // Eventually used rotations or shears are lost
                    return false;
                }
                else
                {
                    // no shear
                    // calculate rotation of X unit vector relative to (1, 0)
                    rRotate = atan2(aUnitVecX.getY(), aUnitVecX.getX());

                    // use orientation to evtl. correct sign of Y-Scale
                    const double fCrossXY(aUnitVecX.cross(aUnitVecY));

                    if(fCrossXY < 0.0)
                    {
                        rScale.setY(-rScale.getY());
                    }
                }
            }
            else
            {
                // fScalarXY is not zero, thus both unit vectors exist. No need to handle that here
                // shear, extract it
                double fCrossXY(aUnitVecX.cross(aUnitVecY));

                // get rotation by calculating angle of X unit vector relative to (1, 0).
                // This is before the parallell test following the motto to extract
                // as much as possible
                rRotate = atan2(aUnitVecX.getY(), aUnitVecX.getX());

                // get unsigned scale value for X. It will not change and is useful
                // for further corrections
                rScale.setX(aUnitVecX.getLength());

                if(fTools::equalZero(fCrossXY))
                {
                    // extract as much as possible
                    rScale.setY(aUnitVecY.getLength());

                    // unit vectors are parallel, thus not linear independent. No
                    // useful decomposition possible. This should not happen since
                    // the only way to get the unit vectors nearly parallell is
                    // a very big shearing. Anyways, be prepared for hand-filled
                    // matrices
                    // Eventually used rotations or shears are lost
                    return false;
                }
                else
                {
                    // calculate the contained shear
                    rShearX = fScalarXY / fCrossXY;

                    if(!fTools::equalZero(rRotate))
                    {
                        // To be able to correct the shear for aUnitVecY, rotation needs to be
                        // removed first. Correction of aUnitVecX is easy, it will be rotated back to (1, 0).
                        aUnitVecX.setX(rScale.getX());
                        aUnitVecX.setY(0.0);

                        // for Y correction we rotate the UnitVecY back about -rRotate
                        const double fNegRotate(-rRotate);
                        const double fSin(sin(fNegRotate));
                        const double fCos(cos(fNegRotate));

                        const double fNewX(aUnitVecY.getX() * fCos - aUnitVecY.getY() * fSin);
                        const double fNewY(aUnitVecY.getX() * fSin + aUnitVecY.getY() * fCos);

                        aUnitVecY.setX(fNewX);
                        aUnitVecY.setY(fNewY);
                    }

                    // Correct aUnitVecY and fCrossXY to fShear=0. Rotation is already removed.
                    // Shear correction can only work with removed rotation
                    aUnitVecY.setX(aUnitVecY.getX() - (aUnitVecY.getY() * rShearX));
                    fCrossXY = aUnitVecX.cross(aUnitVecY);

                    // calculate unsigned scale value for Y, after the corrections since
                    // the shear correction WILL change the length of aUnitVecY
                    rScale.setY(aUnitVecY.getLength());

                    // use orientation to set sign of Y-Scale
                    if(fCrossXY < 0.0)
                    {
                        rScale.setY(-rScale.getY());
                    }
                }
            }
        }

        return true;
    }

/* Old version: Used 3D decompose when shaer was involved and also a determinant test
   (but only in that case). Keeping as comment since it also worked and to allow a
   fallback in case the new version makes trouble somehow. Definitely missing in the 2nd
   case is the sign correction for Y-Scale, this would need to be added following the above
   pattern

    bool B2DHomMatrix::decompose(B2DTuple& rScale, B2DTuple& rTranslate, double& rRotate, double& rShearX) const
    {
        // when perspective is used, decompose is not made here
        if(!mpImpl->isLastLineDefault())
            return false;

        // test for rotation and shear
        if(fTools::equalZero(get(0, 1))
           && fTools::equalZero(get(1, 0)))
        {
            // no rotation and shear, direct value extraction
            rRotate = rShearX = 0.0;

            // copy scale values
            rScale.setX(get(0, 0));
            rScale.setY(get(1, 1));

            // copy translation values
            rTranslate.setX(get(0, 2));
            rTranslate.setY(get(1, 2));

            return true;
        }
        else
        {
            // test if shear is zero. That's the case, if the unit vectors in the matrix
            // are perpendicular -> scalar is zero
            const ::basegfx::B2DVector aUnitVecX(get(0, 0), get(1, 0));
            const ::basegfx::B2DVector aUnitVecY(get(0, 1), get(1, 1));

            if(fTools::equalZero(aUnitVecX.scalar(aUnitVecY)))
            {
                // no shear, direct value extraction
                rShearX = 0.0;

                // calculate rotation
                rShearX = 0.0;
                rRotate = atan2(aUnitVecX.getY(), aUnitVecX.getX());

                // calculate scale values
                rScale.setX(aUnitVecX.getLength());
                rScale.setY(aUnitVecY.getLength());

                // copy translation values
                rTranslate.setX(get(0, 2));
                rTranslate.setY(get(1, 2));

                return true;
            }
            else
            {
                // If determinant is zero, decomposition is not possible
                if(0.0 == determinant())
                    return false;

                // copy 2x2 matrix and translate vector to 3x3 matrix
                ::basegfx::B3DHomMatrix a3DHomMat;

                a3DHomMat.set(0, 0, get(0, 0));
                a3DHomMat.set(0, 1, get(0, 1));
                a3DHomMat.set(1, 0, get(1, 0));
                a3DHomMat.set(1, 1, get(1, 1));
                a3DHomMat.set(0, 3, get(0, 2));
                a3DHomMat.set(1, 3, get(1, 2));

                ::basegfx::B3DTuple r3DScale, r3DTranslate, r3DRotate, r3DShear;

                if(a3DHomMat.decompose(r3DScale, r3DTranslate, r3DRotate, r3DShear))
                {
                    // copy scale values
                    rScale.setX(r3DScale.getX());
                    rScale.setY(r3DScale.getY());

                    // copy shear
                    rShearX = r3DShear.getX();

                    // copy rotate
                    rRotate = r3DRotate.getZ();

                    // copy translate
                    rTranslate.setX(r3DTranslate.getX());
                    rTranslate.setY(r3DTranslate.getY());

                    return true;
                }
            }
        }

        return false;
    } */

} // end of namespace basegfx

// eof