qmatrix.cpp

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#include "qdatastream.h"
#include "qdebug.h"
#include "qmatrix.h"
#include "qregion.h"
#include "qpainterpath.h"
#include "qvariant.h"
#include <qmath.h>

#include <limits.h>

QT_BEGIN_NAMESPACE

// some defines to inline some code
#define MAPDOUBLE(x, y, nx, ny) \
{ \
    qreal fx = x; \
    qreal fy = y; \
    nx = _m11*fx + _m21*fy + _dx; \
    ny = _m12*fx + _m22*fy + _dy; \
}

#define MAPINT(x, y, nx, ny) \
{ \
    qreal fx = x; \
    qreal fy = y; \
    nx = qRound(_m11*fx + _m21*fy + _dx); \
    ny = qRound(_m12*fx + _m22*fy + _dy); \
}

/*****************************************************************************
  QMatrix member functions
 *****************************************************************************/
QMatrix::QMatrix()
    : _m11(1.)
    , _m12(0.)
    , _m21(0.)
    , _m22(1.)
    , _dx(0.)
    , _dy(0.)
{
}

QMatrix::QMatrix(qreal m11, qreal m12, qreal m21, qreal m22, qreal dx, qreal dy)
    : _m11(m11)
    , _m12(m12)
    , _m21(m21)
    , _m22(m22)
    , _dx(dx)
    , _dy(dy)
{
}


QMatrix::QMatrix(const QMatrix &matrix)
    : _m11(matrix._m11)
    , _m12(matrix._m12)
    , _m21(matrix._m21)
    , _m22(matrix._m22)
    , _dx(matrix._dx)
    , _dy(matrix._dy)
{
}

void QMatrix::setMatrix(qreal m11, qreal m12, qreal m21, qreal m22, qreal dx, qreal dy)
{
    _m11 = m11;
    _m12 = m12;
    _m21 = m21;
    _m22 = m22;
    _dx  = dx;
    _dy  = dy;
}


void QMatrix::map(qreal x, qreal y, qreal *tx, qreal *ty) const
{
    MAPDOUBLE(x, y, *tx, *ty);
}



void QMatrix::map(int x, int y, int *tx, int *ty) const
{
    MAPINT(x, y, *tx, *ty);
}

QRect QMatrix::mapRect(const QRect &rect) const
{
    QRect result;
    if (_m12 == 0.0F && _m21 == 0.0F) {
        int x = qRound(_m11*rect.x() + _dx);
        int y = qRound(_m22*rect.y() + _dy);
        int w = qRound(_m11*rect.width());
        int h = qRound(_m22*rect.height());
        if (w < 0) {
            w = -w;
            x -= w;
        }
        if (h < 0) {
            h = -h;
            y -= h;
        }
        result = QRect(x, y, w, h);
    } else {
        // see mapToPolygon for explanations of the algorithm.
        qreal x0, y0;
        qreal x, y;
        MAPDOUBLE(rect.left(), rect.top(), x0, y0);
        qreal xmin = x0;
        qreal ymin = y0;
        qreal xmax = x0;
        qreal ymax = y0;
        MAPDOUBLE(rect.right() + 1, rect.top(), x, y);
        xmin = qMin(xmin, x);
        ymin = qMin(ymin, y);
        xmax = qMax(xmax, x);
        ymax = qMax(ymax, y);
        MAPDOUBLE(rect.right() + 1, rect.bottom() + 1, x, y);
        xmin = qMin(xmin, x);
        ymin = qMin(ymin, y);
        xmax = qMax(xmax, x);
        ymax = qMax(ymax, y);
        MAPDOUBLE(rect.left(), rect.bottom() + 1, x, y);
        xmin = qMin(xmin, x);
        ymin = qMin(ymin, y);
        xmax = qMax(xmax, x);
        ymax = qMax(ymax, y);
        result = QRect(qRound(xmin), qRound(ymin), qRound(xmax)-qRound(xmin), qRound(ymax)-qRound(ymin));
    }
    return result;
}

QRectF QMatrix::mapRect(const QRectF &rect) const
{
    QRectF result;
    if (_m12 == 0.0F && _m21 == 0.0F) {
        qreal x = _m11*rect.x() + _dx;
        qreal y = _m22*rect.y() + _dy;
        qreal w = _m11*rect.width();
        qreal h = _m22*rect.height();
        if (w < 0) {
            w = -w;
            x -= w;
        }
        if (h < 0) {
            h = -h;
            y -= h;
        }
        result = QRectF(x, y, w, h);
    } else {
        qreal x0, y0;
        qreal x, y;
        MAPDOUBLE(rect.x(), rect.y(), x0, y0);
        qreal xmin = x0;
        qreal ymin = y0;
        qreal xmax = x0;
        qreal ymax = y0;
        MAPDOUBLE(rect.x() + rect.width(), rect.y(), x, y);
        xmin = qMin(xmin, x);
        ymin = qMin(ymin, y);
        xmax = qMax(xmax, x);
        ymax = qMax(ymax, y);
        MAPDOUBLE(rect.x() + rect.width(), rect.y() + rect.height(), x, y);
        xmin = qMin(xmin, x);
        ymin = qMin(ymin, y);
        xmax = qMax(xmax, x);
        ymax = qMax(ymax, y);
        MAPDOUBLE(rect.x(), rect.y() + rect.height(), x, y);
        xmin = qMin(xmin, x);
        ymin = qMin(ymin, y);
        xmax = qMax(xmax, x);
        ymax = qMax(ymax, y);
        result = QRectF(xmin, ymin, xmax-xmin, ymax - ymin);
    }
    return result;
}

QPoint QMatrix::map(const QPoint &p) const
{
    qreal fx = p.x();
    qreal fy = p.y();
    return QPoint(qRound(_m11*fx + _m21*fy + _dx),
                   qRound(_m12*fx + _m22*fy + _dy));
}

QPointF QMatrix::map(const QPointF &point) const
{
    qreal fx = point.x();
    qreal fy = point.y();
    return QPointF(_m11*fx + _m21*fy + _dx, _m12*fx + _m22*fy + _dy);
}

QLineF QMatrix::map(const QLineF &line) const
{
    return QLineF(map(line.p1()), map(line.p2()));
}

QLine QMatrix::map(const QLine &line) const
{
    return QLine(map(line.p1()), map(line.p2()));
}

QPolygon QMatrix::map(const QPolygon &a) const
{
    int size = a.size();
    int i;
    QPolygon p(size);
    const QPoint *da = a.constData();
    QPoint *dp = p.data();
    for(i = 0; i < size; i++) {
        MAPINT(da[i].x(), da[i].y(), dp[i].rx(), dp[i].ry());
    }
    return p;
}

QPolygonF QMatrix::map(const QPolygonF &a) const
{
    int size = a.size();
    int i;
    QPolygonF p(size);
    const QPointF *da = a.constData();
    QPointF *dp = p.data();
    for(i = 0; i < size; i++) {
        MAPDOUBLE(da[i].xp, da[i].yp, dp[i].xp, dp[i].yp);
    }
    return p;
}

extern Q_AUTOTEST_EXPORT QPainterPath qt_regionToPath(const QRegion &region);

QRegion QMatrix::map(const QRegion &r) const
{
    if (_m11 == 1.0 && _m22 == 1.0 && _m12 == 0.0 && _m21 == 0.0) { // translate or identity
        if (_dx == 0.0 && _dy == 0.0) // Identity
            return r;
        QRegion copy(r);
        copy.translate(qRound(_dx), qRound(_dy));
        return copy;
    }

    QPainterPath p = map(qt_regionToPath(r));
    return p.toFillPolygon().toPolygon();
}

QPainterPath QMatrix::map(const QPainterPath &path) const
{
    if (path.isEmpty())
        return QPainterPath();

    QPainterPath copy = path;

    // Translate or identity
    if (_m11 == 1.0 && _m22 == 1.0 && _m12 == 0.0 && _m21 == 0.0) {

        // Translate
        if (_dx != 0.0 || _dy != 0.0) {
            copy.detach();
            for (int i=0; i<path.elementCount(); ++i) {
                QPainterPath::Element &e = copy.d_ptr->elements[i];
                e.x += _dx;
                e.y += _dy;
            }
        }

    // Full xform
    } else {
        copy.detach();
        for (int i=0; i<path.elementCount(); ++i) {
            QPainterPath::Element &e = copy.d_ptr->elements[i];
            qreal fx = e.x, fy = e.y;
            e.x = _m11*fx + _m21*fy + _dx;
            e.y =  _m12*fx + _m22*fy + _dy;
        }
    }

    return copy;
}

#ifdef QT3_SUPPORT
QRegion QMatrix::mapToRegion(const QRect &rect) const
{
    QRegion result;
    if (isIdentity()) {
        result = rect;
    } else if (m12() == 0.0F && m21() == 0.0F) {
        int x = qRound(m11()*rect.x() + dx());
        int y = qRound(m22()*rect.y() + dy());
        int w = qRound(m11()*rect.width());
        int h = qRound(m22()*rect.height());
        if (w < 0) {
            w = -w;
            x -= w - 1;
        }
        if (h < 0) {
            h = -h;
            y -= h - 1;
        }
        result = QRect(x, y, w, h);
    } else {
        result = QRegion(mapToPolygon(rect));
    }
    return result;

}
#endif

QPolygon QMatrix::mapToPolygon(const QRect &rect) const
{
    QPolygon a(4);
    qreal x[4], y[4];
    if (_m12 == 0.0F && _m21 == 0.0F) {
        x[0] = _m11*rect.x() + _dx;
        y[0] = _m22*rect.y() + _dy;
        qreal w = _m11*rect.width();
        qreal h = _m22*rect.height();
        if (w < 0) {
            w = -w;
            x[0] -= w;
        }
        if (h < 0) {
            h = -h;
            y[0] -= h;
        }
        x[1] = x[0]+w;
        x[2] = x[1];
        x[3] = x[0];
        y[1] = y[0];
        y[2] = y[0]+h;
        y[3] = y[2];
    } else {
        qreal right = rect.x() + rect.width();
        qreal bottom = rect.y() + rect.height();
        MAPDOUBLE(rect.x(), rect.y(), x[0], y[0]);
        MAPDOUBLE(right, rect.y(), x[1], y[1]);
        MAPDOUBLE(right, bottom, x[2], y[2]);
        MAPDOUBLE(rect.x(), bottom, x[3], y[3]);
    }
#if 0
    int i;
    for(i = 0; i< 4; i++)
        qDebug("coords(%d) = (%f/%f) (%d/%d)", i, x[i], y[i], qRound(x[i]), qRound(y[i]));
    qDebug("width=%f, height=%f", qSqrt((x[1]-x[0])*(x[1]-x[0]) + (y[1]-y[0])*(y[1]-y[0])),
            qSqrt((x[0]-x[3])*(x[0]-x[3]) + (y[0]-y[3])*(y[0]-y[3])));
#endif
    // all coordinates are correctly, tranform to a pointarray
    // (rounding to the next integer)
    a.setPoints(4, qRound(x[0]), qRound(y[0]),
                 qRound(x[1]), qRound(y[1]),
                 qRound(x[2]), qRound(y[2]),
                 qRound(x[3]), qRound(y[3]));
    return a;
}

void QMatrix::reset()
{
    _m11 = _m22 = 1.0;
    _m12 = _m21 = _dx = _dy = 0.0;
}

QMatrix &QMatrix::translate(qreal dx, qreal dy)
{
    _dx += dx*_m11 + dy*_m21;
    _dy += dy*_m22 + dx*_m12;
    return *this;
}

QMatrix &QMatrix::scale(qreal sx, qreal sy)
{
    _m11 *= sx;
    _m12 *= sx;
    _m21 *= sy;
    _m22 *= sy;
    return *this;
}

QMatrix &QMatrix::shear(qreal sh, qreal sv)
{
    qreal tm11 = sv*_m21;
    qreal tm12 = sv*_m22;
    qreal tm21 = sh*_m11;
    qreal tm22 = sh*_m12;
    _m11 += tm11;
    _m12 += tm12;
    _m21 += tm21;
    _m22 += tm22;
    return *this;
}

const qreal deg2rad = qreal(0.017453292519943295769);        // pi/180

QMatrix &QMatrix::rotate(qreal a)
{
    qreal sina = 0;
    qreal cosa = 0;
    if (a == 90. || a == -270.)
        sina = 1.;
    else if (a == 270. || a == -90.)
        sina = -1.;
    else if (a == 180.)
        cosa = -1.;
    else{
        qreal b = deg2rad*a;                        // convert to radians
        sina = qSin(b);               // fast and convenient
        cosa = qCos(b);
    }
    qreal tm11 = cosa*_m11 + sina*_m21;
    qreal tm12 = cosa*_m12 + sina*_m22;
    qreal tm21 = -sina*_m11 + cosa*_m21;
    qreal tm22 = -sina*_m12 + cosa*_m22;
    _m11 = tm11; _m12 = tm12;
    _m21 = tm21; _m22 = tm22;
    return *this;
}

QMatrix QMatrix::inverted(bool *invertible) const
{
    qreal dtr = determinant();
    if (dtr == 0.0) {
        if (invertible)
            *invertible = false;                // singular matrix
        return QMatrix(true);
    }
    else {                                        // invertible matrix
        if (invertible)
            *invertible = true;
        qreal dinv = 1.0/dtr;
        return QMatrix((_m22*dinv),        (-_m12*dinv),
                       (-_m21*dinv), (_m11*dinv),
                       ((_m21*_dy - _m22*_dx)*dinv),
                       ((_m12*_dx - _m11*_dy)*dinv),
                       true);
    }
}


bool QMatrix::operator==(const QMatrix &m) const
{
    return _m11 == m._m11 &&
           _m12 == m._m12 &&
           _m21 == m._m21 &&
           _m22 == m._m22 &&
           _dx == m._dx &&
           _dy == m._dy;
}

bool QMatrix::operator!=(const QMatrix &m) const
{
    return _m11 != m._m11 ||
           _m12 != m._m12 ||
           _m21 != m._m21 ||
           _m22 != m._m22 ||
           _dx != m._dx ||
           _dy != m._dy;
}

QMatrix &QMatrix::operator *=(const QMatrix &m)
{
    qreal tm11 = _m11*m._m11 + _m12*m._m21;
    qreal tm12 = _m11*m._m12 + _m12*m._m22;
    qreal tm21 = _m21*m._m11 + _m22*m._m21;
    qreal tm22 = _m21*m._m12 + _m22*m._m22;

    qreal tdx  = _dx*m._m11  + _dy*m._m21 + m._dx;
    qreal tdy =  _dx*m._m12  + _dy*m._m22 + m._dy;

    _m11 = tm11; _m12 = tm12;
    _m21 = tm21; _m22 = tm22;
    _dx = tdx; _dy = tdy;
    return *this;
}

QMatrix QMatrix::operator *(const QMatrix &m) const
{
    qreal tm11 = _m11*m._m11 + _m12*m._m21;
    qreal tm12 = _m11*m._m12 + _m12*m._m22;
    qreal tm21 = _m21*m._m11 + _m22*m._m21;
    qreal tm22 = _m21*m._m12 + _m22*m._m22;

    qreal tdx  = _dx*m._m11  + _dy*m._m21 + m._dx;
    qreal tdy =  _dx*m._m12  + _dy*m._m22 + m._dy;
    return QMatrix(tm11, tm12, tm21, tm22, tdx, tdy, true);
}

QMatrix &QMatrix::operator=(const QMatrix &matrix)
{
    _m11 = matrix._m11;
    _m12 = matrix._m12;
    _m21 = matrix._m21;
    _m22 = matrix._m22;
    _dx  = matrix._dx;
    _dy  = matrix._dy;
    return *this;
}

QMatrix::operator QVariant() const
{
    return QVariant(QVariant::Matrix, this);
}

Q_GUI_EXPORT QPainterPath operator *(const QPainterPath &p, const QMatrix &m)
{
    return m.map(p);
}


/*****************************************************************************
  QMatrix stream functions
 *****************************************************************************/
#ifndef QT_NO_DATASTREAM

QDataStream &operator<<(QDataStream &s, const QMatrix &m)
{
    if (s.version() == 1) {
        s << (float)m.m11() << (float)m.m12() << (float)m.m21()
          << (float)m.m22() << (float)m.dx()  << (float)m.dy();
    } else {
        s << double(m.m11())
          << double(m.m12())
          << double(m.m21())
          << double(m.m22())
          << double(m.dx())
          << double(m.dy());
    }
    return s;
}

QDataStream &operator>>(QDataStream &s, QMatrix &m)
{
    if (s.version() == 1) {
        float m11, m12, m21, m22, dx, dy;
        s >> m11;  s >> m12;  s >> m21;  s >> m22;
        s >> dx;   s >> dy;
        m.setMatrix(m11, m12, m21, m22, dx, dy);
    }
    else {
        double m11, m12, m21, m22, dx, dy;
        s >> m11;
        s >> m12;
        s >> m21;
        s >> m22;
        s >> dx;
        s >> dy;
        m.setMatrix(m11, m12, m21, m22, dx, dy);
    }
    return s;
}
#endif // QT_NO_DATASTREAM

#ifndef QT_NO_DEBUG_STREAM
QDebug operator<<(QDebug dbg, const QMatrix &m)
{
    dbg.nospace() << "QMatrix("
                  << "11=" << m.m11()
                  << " 12=" << m.m12()
                  << " 21=" << m.m21()
                  << " 22=" << m.m22()
                  << " dx=" << m.dx()
                  << " dy=" << m.dy()
                  << ')';
    return dbg.space();
}
#endif

QT_END_NAMESPACE