qpainter.3qt

Trolltech公司发布的基于C++图形开发环境

.PP
The window rectangle is part of the view transformation. The window specifies the logical coordinate system. Its sister, the viewport(), specifies the device coordinate system.
.PP
The default window rectangle is the same as the device's rectangle. See the Coordinate System Overview for an overview of coordinate transformation.
.PP
See also window(), setViewport(), setViewXForm(), setWorldMatrix() and setWorldXForm().
.PP
Examples:
.(l
drawdemo/drawdemo.cpp
.)l
.SH "void QPainter::setWindow ( const QRect & r )"
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
.SH "void QPainter::setWorldMatrix ( const QWMatrix & m, bool combine=FALSE )"
Sets the world transformation matrix to \fIm\fR and enables world transformation.
.PP
If \fIcombine\fR is TRUE, then \fIm\fR is combined with the current transformation matrix, otherwise \fIm\fR replaces the current transformation matrix.
.PP
If \fIm\fR the identity matrix and \fIcombine\fR is FALSE, this function calls setWorldXForm(FALSE). (The identity matrix is the matrix where QWMatrix::m11() and QWMatrix::m22() are 1.0 and the rest are 0.0.)
.PP
World transformations are applied after the view transformations (i.e. window and viewport).
.PP
The following functions can transform the coordinate system without using a QWMatrix:
.TP
translate()
.TP
scale()
.TP
shear()
.TP
rotate()
.PP
They operate on the painter's worldMatrix() and are implemented like this:
.PP
.nf
.br
    void QPainter::rotate( double a )
.br
    {
.br
        QWMatrix m;
.br
        m.rotate( a );
.br
        setWorldMatrix( m, TRUE );
.br
    }
.fi
.PP
Note that you should always use \fIcombine\fR when you are drawing into a QPicture. Otherwise it may not be possible to replay the picture with additional transformations. Using translate(), scale(), etc. is safe.
.PP
For a brief overview of coordinate transformation, see the Coordinate System Overview.
.PP
See also worldMatrix(), setWorldXForm(), setWindow(), setViewport(), setViewXForm(), xForm() and QWMatrix.
.PP
Examples:
.(l
drawdemo/drawdemo.cpp
.)l
.SH "void QPainter::setWorldXForm ( bool enable )"
Enables world transformations if \fIenable\fR is TRUE, or disables world transformations if \fIenable\fR is FALSE. The world transformation matrix is not changed.
.PP
See also setWorldMatrix(), setWindow(), setViewport(), setViewXForm() and xForm().
.SH "void QPainter::shear ( double sh, double sv )"
Shears the coordinate system \fI(sh,sv).\fR
.PP
See also translate(), scale(), rotate(), resetXForm(), setWorldMatrix() and xForm().
.SH "int * QPainter::tabArray () const"
Returns the currently set tab stop array.
.PP
See also setTabArray().
.SH "int QPainter::tabStops () const"
Returns the tab stop setting.
.PP
See also setTabStops().
.SH "void QPainter::translate ( double dx, double dy )"
Translates the coordinate system by \fI(dx,dy).\fR
.PP
For example, the following code draws a single vertical line 20 pixels high.
.PP
.nf
.br
    void MyWidget::paintEvent()
.br
    {
.br
        QPainter paint( this );
.br
        paint.drawLine(10,0,10,20);
.br
        paint.translate(100.0,100.0);
.br
        paint.drawLine(-90,-80,-90,-70);
.br
    }
.fi
.PP
See also scale(), shear(), rotate(), resetXForm(), setWorldMatrix() and xForm().
.SH "QRect QPainter::viewport () const"
Returns the viewport rectangle.
.PP
See also setViewport() and setViewXForm().
.SH "QRect QPainter::window () const"
Returns the window rectangle.
.PP
See also setWindow() and setViewXForm().
.SH "const QWMatrix & QPainter::worldMatrix () const"
Returns the world transformation matrix.
.PP
See also setWorldMatrix().
.SH "QPoint QPainter::xForm ( const QPoint & pv ) const"
Returns the point \fIpv\fR transformed from model coordinates to device coordinates.
.PP
See also xFormDev() and QWMatrix::map().
.SH "QPointArray QPainter::xForm ( const QPointArray & av ) const"
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
.PP
Returns the point array \fIav\fR transformed from model coordinates to device coordinates.
.PP
See also xFormDev() and QWMatrix::map().
.SH "QPointArray QPainter::xForm ( const QPointArray & av, int index, int npoints ) const"
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
.PP
Returns the point array \fIav\fR transformed from model coordinates to device coordinates. The \fIindex\fR is the first point in the array and \fInpoints\fR denotes the number of points to be transformed. If \fInpoints\fR is negative, all points from \fIav[index]\fR until the last point in the array are transformed.
.PP
The returned point array consists of the number of points that were transformed.
.PP
Example:
.PP
.nf
.br
    QPointArray a(10);
.br
    QPointArray b;
.br
    b = painter.xForm(a,2,4);   // b.size() == 4
.br
    b = painter.xForm(a,2,-1);  // b.size() == 8
.fi
.PP
See also xFormDev() and QWMatrix::map().
.SH "QRect QPainter::xForm ( const QRect & rv ) const"
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
.PP
Returns the rectangle \fIrv\fR transformed from model coordinates to device coordinates.
.PP
If world transformation is enabled and rotation or shearing has been specified, then the bounding rectangle is returned.
.PP
See also xFormDev() and QWMatrix::map().
.SH "QPoint QPainter::xFormDev ( const QPoint & pd ) const"
Returns the point \fIpd\fR transformed from device coordinates to model coordinates.
.PP
See also xForm() and QWMatrix::map().
.SH "QPointArray QPainter::xFormDev ( const QPointArray & ad ) const"
Returns the point array \fIad\fR transformed from device coordinates to model coordinates.
.PP
See also xForm() and QWMatrix::map().
.SH "QRect QPainter::xFormDev ( const QRect & rd ) const"
Returns the rectangle \fIrd\fR transformed from device coordinates to model coordinates.
.PP
If world transformation is enabled and rotation or shearing is used, then the bounding rectangle is returned.
.PP
See also xForm() and QWMatrix::map().
.SH "QPointArray QPainter::xFormDev ( const QPointArray & ad, int index, int npoints ) const"
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
.PP
Returns the point array \fIad\fR transformed from device coordinates to model coordinates. The \fIindex\fR is the first point in the array and \fInpoints\fR denotes the number of points to be transformed. If \fInpoints\fR is negative, all points from \fIad[index]\fR until the last point in the array are transformed.
.PP
The returned point array consists of the number of points that were transformed.
.PP
Example:
.PP
.nf
.br
    QPointArray a(10);
.br
    QPointArray b;
.br
    b = painter.xFormDev(a,1,3);        // b.size() == 3
.br
    b = painter.xFormDev(a,1,-1);       // b.size() == 9
.fi
.PP
See also xForm() and QWMatrix::map().
.SH RELATED FUNCTION DOCUMENTATION
.SH "void qDrawPlainRect (QPainter * p, int x, int y, int w, int h, const QColor & c, int lineWidth, const QBrush * fill)"
\fC#include <qdrawutil.h>\fR
.PP
Draws a plain rectangle given by (\fIx, y, w, h)\fR using the painter \fIp.\fR
.PP
The color argument \fIc\fR specifies the line color.
.PP
The \fIlineWidth\fR argument specifies the line width.
.PP
The rectangle interior is filled with the \fIfill\fR brush unless \fIfill\fR is null.
.PP
If you want to use a QFrame widget instead, you can make it display a plain rectangle, for example \fCQFrame::setFrameStyle( QFrame::Box | QFrame::Plain )\fR.
.PP
\fBWarning:\fR This function does not look at QWidget::style() or QApplication::style(). Use the drawing functions in QStyle to make widgets that follow the current GUI style.
.PP
See also qDrawShadeRect() and QStyle::drawRect().
.SH "void qDrawWinPanel (QPainter * p, int x, int y, int w, int h, const QColorGroup & g, bool sunken, const QBrush * fill)"
\fC#include <qdrawutil.h>\fR
.PP
Draws a Windows-style panel given by (\fIx, y, w, h)\fR using the painter \fIp.\fR
.PP
The color group argument \fIg\fR specifies the shading colors.
.PP
The panel appears sunken if \fIsunken\fR is TRUE, or raised if \fIsunken\fR is FALSE.
.PP
The line width is 2 pixels.
.PP
The button interior is filled with the \fIfill\fR brush unless \fIfill\fR is null.
.PP
If you want to use a QFrame widget instead, you can make it display a shaded panel, for example \fCQFrame::setFrameStyle( QFrame::WinPanel | QFrame::Raised )\fR.
.PP
\fBWarning:\fR This function does not look at QWidget::style() or QApplication::style(). Use the drawing functions in QStyle to make widgets that follow the current GUI style.
.PP
See also qDrawShadePanel(), qDrawWinButton() and QStyle::drawPanel().
.SH "void qDrawShadeLine (QPainter * p, int x1, int y1, int x2, int y2, const QColorGroup & g, bool sunken, int lineWidth, int midLineWidth)"
\fC#include <qdrawutil.h>\fR
.PP
Draws a horizontal (\fIy1\fR == \fIy2)\fR or vertical (\fIx1\fR == \fIx2)\fR shaded line using the painter \fIp.\fR
.PP
Nothing is drawn if \fIy1\fR != \fIy2\fR and \fIx1\fR != \fIx2\fR (i.e. the line is neither horizontal nor vertical).
.PP
The color group argument \fIg\fR specifies the shading colors (light, dark and middle colors).
.PP
The line appears sunken if \fIsunken\fR is TRUE, or raised if \fIsunken\fR is FALSE.
.PP
The \fIlineWidth\fR argument specifies the line width for each of the lines. It is not the total line width.
.PP
The \fImidLineWidth\fR argument specifies the width of a middle line drawn in the QColorGroup::mid() color.
.PP
If you want to use a QFrame widget instead, you can make it display a shaded line, for example \fCQFrame::setFrameStyle( QFrame::HLine | QFrame::Sunken )\fR.
.PP
\fBWarning:\fR This function does not look at QWidget::style() or QApplication::style(). Use the drawing functions in QStyle to make widgets that follow the current GUI style.
.PP
See also qDrawShadeRect(), qDrawShadePanel() and QStyle::drawSeparator().
.SH "void qDrawShadeRect (QPainter * p, int x, int y, int w, int h, const QColorGroup & g, bool sunken, int lineWidth, int midLineWidth, const QBrush * fill)"
\fC#include <qdrawutil.h>\fR
.PP
Draws a shaded rectangle/box given by (\fIx, y, w, h)\fR using the painter \fIp.\fR
.PP
The color group argument \fIg\fR specifies the shading colors (light, dark and middle colors).
.PP
The rectangle appears sunken if \fIsunken\fR is TRUE, or raised if \fIsunken\fR is FALSE.
.PP
The \fIlineWidth\fR argument specifies the line width for each of the lines. It is not the total line width.
.PP
The \fImidLineWidth\fR argument specifies the width of a middle line drawn in the QColorGroup::mid() color.
.PP
The rectangle interior is filled with the \fIfill\fR brush unless \fIfill\fR is null.
.PP
If you want to use a QFrame widget instead, you can make it display a shaded rectangle, for example \fCQFrame::setFrameStyle( QFrame::Box | QFrame::Raised )\fR.
.PP
\fBWarning:\fR This function does not look at QWidget::style() or QApplication::style(). Use the drawing functions in QStyle to make widgets that follow the current GUI style.
.PP
See also qDrawShadeLine(), qDrawShadePanel(), qDrawPlainRect(), QStyle::drawRect() and QStyle::drawRectStrong().
.SH "void qDrawShadePanel (QPainter * p, int x, int y, int w, int h, const QColorGroup & g, bool sunken, int lineWidth, const QBrush * fill)"
\fC#include <qdrawutil.h>\fR
.PP
Draws a shaded panel given by (\fIx, y, w, h)\fR using the painter \fIp.\fR
.PP
The color group argument \fIg\fR specifies the shading colors (light, dark and middle colors).
.PP
The panel appears sunken if \fIsunken\fR is TRUE, or raised if \fIsunken\fR is FALSE.
.PP
The \fIlineWidth\fR argument specifies the line width.
.PP
The panel interior is filled with the \fIfill\fR brush unless \fIfill\fR is null.
.PP
If you want to use a QFrame widget instead, you can make it display a shaded panel, for example \fCQFrame::setFrameStyle( QFrame::Panel | QFrame::Sunken )\fR.
.PP
\fBWarning:\fR This function does not look at QWidget::style() or QApplication::style(). Use the drawing functions in QStyle to make widgets that follow the current GUI style.
.PP
See also qDrawWinPanel(), qDrawShadeLine(), qDrawShadeRect() and QStyle::drawPanel().
.SH "void qDrawWinButton (QPainter * p, int x, int y, int w, int h, const QColorGroup & g, bool sunken, const QBrush * fill)"
\fC#include <qdrawutil.h>\fR
.PP
Draws a Windows-style button given by (\fIx, y, w, h)\fR using the painter \fIp.\fR
.PP
The color group argument \fIg\fR specifies the shading colors (light, dark and middle colors).
.PP
The button appears sunken if \fIsunken\fR is TRUE, or raised if \fIsunken\fR is FALSE.
.PP
The line width is 2 pixels.
.PP
The button interior is filled with the \fI*fill\fR brush unless \fIfill\fR is null.
.PP
\fBWarning:\fR This function does not look at QWidget::style() or QApplication::style(). Use the drawing functions in QStyle to make widgets that follow the current GUI style.
.PP
See also  qDrawWinPanel() and QStyle::drawButton().
.SH "SEE ALSO"
.BR http://doc.trolltech.com/qpainter.html
.BR http://www.trolltech.com/faq/tech.html
.SH COPYRIGHT
Copyright 1992-2001 Trolltech AS, http://www.trolltech.com.  See the
license file included in the distribution for a complete license
statement.
.SH AUTHOR
Generated automatically from the source code.
.SH BUGS
If you find a bug in Qt, please report it as described in
.BR http://doc.trolltech.com/bughowto.html .
Good bug reports make our job much simpler. Thank you.
.P
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