QPainter(3qt)QPainter(3qt)NAMEQPainter - Paints on paint devices
#include <qpainter.h>
Inherits Qt.
Public Members
QPainter ()
QPainter ( const QPaintDevice * )
QPainter ( const QPaintDevice *, const QWidget * )
~QPainter ()
bool begin ( const QPaintDevice * )
bool begin ( const QPaintDevice *, const QWidget * )
bool end ()
QPaintDevice* device () const
bool isActive () const
void flush ()
void save ()
void restore ()
QFontMetrics fontMetrics () const
QFontInfo fontInfo () const
const QFont& font () const
void setFont ( const QFont & )
const QPen& pen () const
void setPen ( const QPen & )
void setPen ( PenStyle )
void setPen ( const QColor & )
const QBrush& brush () const
void setBrush ( const QBrush & )
void setBrush ( BrushStyle )
void setBrush ( const QColor & )
QPoint pos () const
const QColor& backgroundColor () const
void setBackgroundColor ( const QColor & )
BGMode backgroundMode () const
void setBackgroundMode ( BGMode )
RasterOp rasterOp () const
void setRasterOp ( RasterOp )
const QPoint& brushOrigin () const
void setBrushOrigin ( int x, int y )
void setBrushOrigin ( const QPoint & )
bool hasViewXForm () const
bool hasWorldXForm () const
void setViewXForm ( bool )
QRect window () const
void setWindow ( const QRect & )
void setWindow ( int x, int y, int w, int h )
QRect viewport () const
void setViewport ( const QRect & )
void setViewport ( int x, int y, int w, int h )
void setWorldXForm ( bool )
const QWMatrix& worldMatrix () const
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void setWorldMatrix ( const QWMatrix &, bool combine=FALSE
)
void saveWorldMatrix () (obsolete)
void restoreWorldMatrix () (obsolete)
void scale ( double sx, double sy )
void shear ( double sh, double sv )
void rotate ( double a )
void translate ( double dx, double dy )
void resetXForm ()
QPoint xForm ( const QPoint & ) const
QRect xForm ( const QRect & ) const
QPointArray xForm ( const QPointArray & ) const
QPointArray xForm ( const QPointArray &, int index, int
npoints ) const
QPoint xFormDev ( const QPoint & ) const
QRect xFormDev ( const QRect & ) const
QPointArray xFormDev ( const QPointArray & ) const
QPointArray xFormDev ( const QPointArray &, int index, int
npoints ) const
void setClipping ( bool )
bool hasClipping () const
const QRegion& clipRegion () const
void setClipRect ( const QRect & )
void setClipRect ( int x, int y, int w, int h )
void setClipRegion ( const QRegion & )
void drawPoint ( int x, int y )
void drawPoint ( const QPoint & )
void drawPoints ( const QPointArray & a, int index=0, int
npoints=-1 )
void moveTo ( int x, int y )
void moveTo ( const QPoint & )
void lineTo ( int x, int y )
void lineTo ( const QPoint & )
void drawLine ( int x1, int y1, int x2, int y2 )
void drawLine ( const QPoint &, const QPoint & )
void drawRect ( int x, int y, int w, int h )
void drawRect ( const QRect & )
void drawWinFocusRect ( int x, int y, int w, int h )
void drawWinFocusRect ( int x, int y, int w, int h, const
QColor & bgColor )
void drawWinFocusRect ( const QRect & )
void drawWinFocusRect ( const QRect &, const QColor &
bgColor )
void drawRoundRect ( int x, int y, int w, int h, int, int
)
void drawRoundRect ( const QRect &, int, int )
void drawRoundRect ( int x, int y, int w, int h )
void drawRoundRect ( const QRect & )
void drawEllipse ( int x, int y, int w, int h )
void drawEllipse ( const QRect & )
void drawArc ( int x, int y, int w, int h, int a, int alen
)
void drawArc ( const QRect &, int a, int alen )
void drawPie ( int x, int y, int w, int h, int a, int alen
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)
void drawPie ( const QRect &, int a, int alen )
void drawChord ( int x, int y, int w, int h, int a, int
alen )
void drawChord ( const QRect &, int a, int alen )
void drawLineSegments ( const QPointArray &, int index=0,
int nlines=-1 )
void drawPolyline ( const QPointArray &, int index=0, int
npoints=-1 )
void drawPolygon ( const QPointArray &, bool
winding=FALSE, int index=0, int npoints=-1 )
void drawQuadBezier ( const QPointArray &, int index=0 )
void drawPixmap ( int x, int y, const QPixmap &, int sx=0,
int sy=0, int sw=-1, int sh=-1 )
void drawPixmap ( const QPoint &, const QPixmap &, const
QRect & sr )
void drawPixmap ( const QPoint &, const QPixmap & )
void drawImage ( int x, int y, const QImage &, int sx=0,
int sy=0, int sw=-1, int sh=-1 )
void drawImage ( const QPoint &, const QImage &, const
QRect & sr )
void drawImage ( const QPoint &, const QImage & )
void drawImage ( int x, int y, const QImage &, int sx, int
sy, int sw, int sh, int conversion_flags )
void drawImage ( const QPoint &, const QImage &, const
QRect & sr, int conversion_flags )
void drawImage ( const QPoint &, const QImage &, int
conversion_flags )
void drawTiledPixmap ( int x, int y, int w, int h, const
QPixmap &, int sx=0, int sy=0 )
void drawTiledPixmap ( const QRect &, const QPixmap &,
const QPoint & )
void drawTiledPixmap ( const QRect &, const QPixmap & )
void drawPicture ( const QPicture & )
void fillRect ( int x, int y, int w, int h, const QBrush &
)
void fillRect ( const QRect &, const QBrush & )
void eraseRect ( int x, int y, int w, int h )
void eraseRect ( const QRect & )
void drawText ( int x, int y, const QString &, int len =
-1 )
void drawText ( const QPoint &, const QString &, int len =
-1 )
void drawText ( int x, int y, int w, int h, int flags,
const QString &, int len = -1, QRect * br=0, char **
internal=0 )
void drawText ( const QRect &, int flags, const QString &,
int len = -1, QRect * br=0, char ** internal=0 )
QRect boundingRect ( int x, int y, int w, int h, int
flags, const QString &, int len = -1, char ** intern=0
)
QRect boundingRect ( const QRect &, int flags, const
QString &, int len = -1, char ** intern=0 )
int tabStops () const
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void setTabStops ( int )
int* tabArray () const
void setTabArray ( int * )
Static Public Members
void redirect ( QPaintDevice * pdev, QPaintDevice *
replacement )
void initialize ()
void cleanup ()
RELATED FUNCTION DOCUMENTATION
(Note that these are not member functions.)
void qDrawPlainRect (QPainter * p, int x, int y, int w,
int h, const QColor & c, int lineWidth, const QBrush *
fill)
void qDrawShadeLine (QPainter * p, int x1, int y1, int x2,
int y2, const QColorGroup & g, bool sunken, int
lineWidth, int midLineWidth)
void qDrawWinButton (QPainter * p, int x, int y, int w,
int h, const QColorGroup & g, bool sunken, const
QBrush * fill)
void qDrawWinPanel (QPainter * p, int x, int y, int w, int
h, const QColorGroup & g, bool sunken, const QBrush *
fill)
void qDrawShadePanel (QPainter * p, int x, int y, int w,
int h, const QColorGroup & g, bool sunken, int
lineWidth, const QBrush * fill)
void qDrawShadeRect (QPainter * p, int x, int y, int w,
int h, const QColorGroup & g, bool sunken, int
lineWidth, int midLineWidth, const QBrush * fill)
DESCRIPTION
The QPainter class paints on paint devices.
The painter provides efficient graphics rendering on any
QPaintDevice object. QPainter can draw everything from
simple lines to complex shapes like pies and chords. It
can also draw aligned text and pixmaps. Normally, it draws
in a "natural" coordinate system, but it can also do view
and world transformation.
The typical use of a painter is:
1 Construct a painter.
2 Set a pen, a brush etc.
3 Draw.
4 Destroy the painter.
Mostly, all this is done inside a paint event. (In fact,
99% of all QPainter use is in a reimplementation of
QWidget::paintEvent()). Here's one very simple example:
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void SimpleExampleWidget::paintEvent()
{
QPainter paint( this );
paint.setPen( Qt::blue );
paint.drawText( rect(), AlignCenter, "The Text" );
}
Simple. However, there are many settings you may use:
font() is the currently set font. If you set a font that
isn't available, Qt finds a close match. In that case
font() returns what you set using setFont() and fontInfo()
returns the font actually being used.
brush() is the currently set brush; the color or pattern
that's used for filling e.g. circles.
pen() is the currently set pen; the color or stipple
that's used for drawing lines or boundaries.
backgroundMode() is Opaque or Transparent, ie. whether
backgroundColor() is used or not.
backgroundColor() only applies when backgroundMode() is
Opaque and pen() is a stipple. In that case, it describes
the color of the background pixels in the stipple.
rasterOp() is how pixels drawn interact with the data
already there.
brushOrigin() is the origin of the tiled brushes, normally
the origin of the window.
viewport(), window(), worldMatrix() and many more make up
the painter's coordinate transformation system. See The
Coordinate System for an explanation of this, or a
paragraph below for a quick overview of the functions.
clipping() is whether the painter clips at all. (The paint
device clips, too.) If the painter clips, it clips to
clipRegion().
pos() is the current position, set by moveTo() and used by
lineTo().
Note that some of these settings mirror settings in some
paint devices, e.g. QWidget::font(). QPainter::begin() (or
the QPainter constructor) copies these attributes from the
paint device, changing calling e.g. QWidget::setFont()
doesn't take effect until the next time a painter begins
painting on it.
save() saves all of these settings on an internal stack,
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QPainter(3qt)QPainter(3qt)restore() pops them back.
The core functionality of QPainter is drawing, and there
are functions to draw most primitives: drawPoint(),
drawPoints(), drawLine(), drawRect(), drawWinFocusRect(),
drawRoundRect(), drawEllipse(), drawArc(), drawPie(),
drawChord(), drawLineSegments(), drawPolyline(),
drawPolygon(), and drawQuadBezier().
There are functions to draw pixmaps/images, namely
drawPixmap(), drawImage() and drawTiledPixmap().
drawPixmap() and drawImage() produce the same result,
except that drawPixmap() is faster on-screen and
drawImage() faster and sometimes better on QPrinter and
QPicture.
Text drawing is done using drawText(), and when you need
fine-grained positioning, boundingRect() tells you where a
given drawText() command would draw.
There is a drawPicture() that draws the contents of an
entire QPicture using this painter. drawPicture() is the
only function that disregards all the painter's settings:
The QPicture has its own settings.
Normally, the QPainter operates on the device's own
coordinate system (usually pixels), but QPainter has good
support for coordinate transformation. See The Coordinate
System for a more general overview and a walkthrough of a
simple example.
The most common functions used are scale(), rotate(),
translate() and shear(), all of which operate on the
worldMatrix(). setWorldMatrix() can replace or add to the
currently set matrix().
setViewport() sets the rectangle on which QPainter
operates. The default is the entire device, which is
usually fine, except on printers. setWindow() sets the
coordinate system, that is, the rectangle that maps to
viewport(). What's draws inside the window() ends up being
inside the viewport(). The window's default is the same as
the viewport, and if you don't use the transformations,
they are optimized away, gaining a little speed.
After all the coordinate transformation is done, QPainter
can clip the drawing to and arbitrary rectangle or region.
hasClipping() is TRUE if QPainter clips, and clipRegion()
returns the clip region. You can set it using either
setClipRegion() or setClipRect(). Note that the clipping
can be slow. It's all system-dependent, but as a rule of
thumb, you can assume that drawing speed is inversely
proportional to the number of rectangles in the clip
region.
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After QPainter's clipping, the paint device too will clip
a bit. For example, most widgets clip away the pixels used
by child widgets, and most printers clip away an area near
the edges of the paper. This additional clipping is not
reflected by the return value of clipRegion() or
hasClipping().
Finally, QPainter includes some little-used functions that
are very handy the few times you need them.
isActive() indicates whether the painter is active.
begin() (and the most usual constructor) makes it active.
end() (and the destructor) deactivates it. If the painter
is active, device() returns the paint device on which the
painter paints.
Sometimes it is desirable to make someone else paint on an
unusual QPaintDevice. QPainter supports a static function
to do this, redirect(). We recommend not using it, but for
some hacks it's perfect.
setTabStops() and setTabArray() can change where the tab
stops are, but these are very seldomly used.
Warning: Note that QPainter does not attempt to work
around coordinate limitations in the underlying window
system. Some platforms may behave incorrectly with
coordinates as small as +/- 4000.
See also QPaintDevice, QWidget, QPixmap, QPrinter,
QPicture, Application Walkthrough and Coordinate System
Overview
Examples: qtimage/qtimage.cpp grapher/grapher.cpp
drawlines/connect.cpp xform/xform.cpp
drawdemo/drawdemo.cpp menu/menu.cpp progress/progress.cpp
qmag/qmag.cpp splitter/splitter.cpp forever/forever.cpp
desktop/desktop.cpp scrollview/scrollview.cpp
trivial/trivial.cpp movies/main.cpp picture/picture.cpp
MEMBER FUNCTION DOCUMENTATIONQPainter::QPainter ()
Constructs a painter.
Notice that all painter settings (setPen,setBrush etc.)
are reset to default values when begin() is called.
See also begin() and end().
QPainter::QPainter ( const QPaintDevice * pd )
Constructs a painter that begins painting the paint device
pd immediately.
This constructor is convenient for short-lived painters,
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e.g. in a paint event and should be used only once. The
constructor calls begin() for you and the QPainter
destructor automatically calls end().
Here's an example using begin() and end():
void MyWidget::paintEvent( QPaintEvent * )
{
QPainter p;
p.begin( this );
p.drawLine( ... ); // drawing code
p.end();
}
The same example using this constructor:
void MyWidget::paintEvent( QPaintEvent * )
{
QPainter p( this );
p.drawLine( ... ); // drawing code
}
See also begin() and end().
QPainter::QPainter ( const QPaintDevice * pd, const QWidget *
copyAttributes )
Constructs a painter that begins painting the paint device
pd immediately, with the default arguments taken from
copyAttributes.
See also begin().
QPainter::~QPainter ()
Destructs the painter.
const QColor & QPainter::backgroundColor () const
Returns the current background color.
See also setBackgroundColor() and QColor.
BGMode QPainter::backgroundMode () const
Returns the current background mode.
See also setBackgroundMode() and BGMode.
bool QPainter::begin ( const QPaintDevice * pd )
Begins painting the paint device pd and returns TRUE if
successful, or FALSE if an error occurs.
The errors that can occur are serious problems, such as
these:
p->begin( 0 ); // impossible - paint device cannot be 0
QPixmap pm( 0, 0 );
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p->begin( pm ); // impossible - pm.isNull();
p->begin( myWidget );
p2->begin( myWidget ); // impossible - only one painter at a time
Note that most of the time, you can use one of the
constructors instead of begin(), and that end() is
automatically done at destruction.
Warning: A paint device can only be painted by one painter
at a time.
See also end() and flush().
Examples: drawdemo/drawdemo.cpp desktop/desktop.cpp
picture/picture.cpp
bool QPainter::begin ( const QPaintDevice * pd, const QWidget *
copyAttributes )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
This version opens the painter on a paint device pd and
sets the initial pen, background color and font from
copyAttributes. This is equivalent with:
QPainter p;
p.begin( pd );
p.setPen( copyAttributes->foregroundColor() );
p.setBackgroundColor( copyAttributes->backgroundColor() );
p.setFont( copyAttributes->font() );
This begin function is convenient for double buffering.
When you draw in a pixmap instead of directly in a widget
(to later bitBlt the pixmap into the widget) you will need
to set the widgets's font etc. This function does exactly
that.
Example:
void MyWidget::paintEvent( QPaintEvent * )
{
QPixmap pm(size());
QPainter p;
p.begin(&pm, this);
// ... potential flickering paint operation ...
p.end();
bitBlt(this, 0, 0, &pm);
}
See also end().
QRect QPainter::boundingRect ( int x, int y, int w, int h, int
tf, const QString & str, int len = -1, char ** internal=0
)
Returns the bounding rectangle of the aligned text that
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function (the first len characters from str). The drawing,
and hence the bounding rectangle, is constrained to the
QPainter(3qt)QPainter(3qt)
rectangle (x,y,w,h).
If len is negative (default value), the whole string is
used.
The tf argument is the bitwise OR of the following flags:
AlignLeft aligns to the left border.
AlignRight aligns to the right border.
AlignHCenter aligns horizontally centered.
AlignTop aligns to the top border.
AlignBottom aligns to the bottom border.
AlignVCenter aligns vertically centered
AlignCenter (= AlignHCenter | AlignVCenter)
SingleLine ignores newline characters in the text.
ExpandTabs expands tabulators.
ShowPrefix interprets "&x" as "x" underlined.
WordBreak breaks the text to fit the rectangle.
Horizontal alignment defaults to AlignLeft and vertical
alignment defaults to AlignTop.
If several of the horizontal or several of the vertical
alignment flags are set, the resulting alignment is
undefined.
These flags are defined in qnamespace.h.
See also drawText(), fontMetrics(),
QFontMetrics::boundingRect() and Qt::AlignmentFlags.
QRect QPainter::boundingRect ( const QRect & r, int tf, const
QString &, int len = -1, char ** i=0 )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
const QBrush & QPainter::brush () const
Returns the current painter brush.
See also QPainter::setBrush().
const QPoint & QPainter::brushOrigin () const
Returns the brush origin currently set.
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See also setBrushOrigin().
void QPainter::cleanup () [static]
Internal function that cleans up the painter.
const QRegion & QPainter::clipRegion () const
Returns the currently set clip region. Note that the clip
region is given in physical device coordinates and not
subject to any coordinate transformation.
See also setClipRegion(), setClipRect() and setClipping().
QPaintDevice * QPainter::device () const
Returns the paint device on which this painter is
currently painting, or null if the painter is not active.
See also QPaintDevice::paintingActive().
void QPainter::drawArc ( int x, int y, int w, int h, int a, int
alen )
Draws an arc defined by the rectangle (x,y,w,h), the start
angle a and the arc length alen.
The angles a and alen are 1/16th of a degree, i.e. a full
circle equals 5760 (16*360). Positive values of a and alen
mean counter-clockwise while negative values mean
clockwise direction. Zero degrees is at the 3'o clock
position.
Example:
QPainter p( myWidget );
p.drawArc( 10,10, 70,100, 100*16, 160*16 ); // draws a "(" arc
See also drawPie() and drawChord().
void QPainter::drawArc ( const QRect & r, int a, int alen )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::drawChord ( int x, int y, int w, int h, int a, int
alen )
Draws a chord defined by the rectangle (x,y,w,h), the
start angle a and the arc length alen.
The chord is filled with the current brush().
The angles a and alen are 1/16th of a degree, i.e. a full
circle equals 5760 (16*360). Positive values of a and alen
mean counter-clockwise while negative values mean
clockwise direction. Zero degrees is at the 3'o clock
position.
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See also drawArc() and drawPie().
void QPainter::drawChord ( const QRect & r, int a, int alen )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::drawEllipse ( int x, int y, int w, int h )
Draws an ellipse with center at (x+w/2,y+h/2) and size
(w,h).
Examples: drawdemo/drawdemo.cpp picture/picture.cpp
void QPainter::drawEllipse ( 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.
void QPainter::drawImage ( int x, int y, const QImage & image,
int sx, int sy, int sw, int sh, int conversion_flags )
Draws at (x, y) the sw by sh area of pixels from (sx, sy)
in image, using conversion_flags if the image needs to be
converted to a pixmap.
This function may convert image to a pixmap and then draw
it, if device() is a QPixmap or a QWidget, or else draw it
directly, if device() is a QPrinter or QPicture.
See also drawPixmap() and QPixmap::convertFromImage().
void QPainter::drawImage ( const QPoint &, const QImage & )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::drawImage ( const QPoint &, const QImage &, const
QRect & sr )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::drawImage ( const QPoint &, const QImage &, const
QRect & sr, int conversion_flags )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::drawImage ( const QPoint &, const QImage &, int
conversion_flags )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
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QPainter(3qt)QPainter(3qt)void QPainter::drawImage ( int x, int y, const QImage & image,
int sx=0, int sy=0, int sw=-1, int sh=-1 )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::drawLine ( int x1, int y1, int x2, int y2 )
Draws a line from (x1,y2) to (x2,y2) and sets (x2,y2) to
be the new current pen position.
See also QPen.
Examples: grapher/grapher.cpp drawlines/connect.cpp
progress/progress.cpp splitter/splitter.cpp
scrollview/scrollview.cpp
void QPainter::drawLine ( const QPoint & p1, const QPoint & p2 )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::drawLineSegments ( const QPointArray & a, int
index=0, int nlines=-1 )
Draws nlines separate lines from points defined in a,
starting at a[index] (index defaults to 0). If nlines is
-1 (the defauls) all points until the end of the array are
used (i.e. (a.size()-index)/2 lines are drawn).
Draws the 1st line from a[index] to a[index+1]. Draws the
2nd line from a[index+2] to a[index+3] etc.
See also drawPolyline(), drawPolygon() and QPen.
void QPainter::drawPicture ( const QPicture & pic )
Replays the picture pic.
This function does exactly the same as QPicture::play().
Examples: picture/picture.cpp
void QPainter::drawPie ( int x, int y, int w, int h, int a, int
alen )
Draws a pie defined by the rectangle (x,y,w,h), the start
angle a and the arc length alen.
The pie is filled with the current brush().
The angles a and alen are 1/16th of a degree, i.e. a full
circle equals 5760 (16*360). Positive values of a and alen
mean counter-clockwise while negative values mean
clockwise direction. Zero degrees is at the 3'o clock
position.
See also drawArc() and drawChord().
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Examples: grapher/grapher.cpp drawdemo/drawdemo.cpp
void QPainter::drawPie ( const QRect & r, int a, int alen )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::drawPixmap ( int x, int y, const QPixmap & pixmap,
int sx=0, int sy=0, int sw=-1, int sh=-1 )
Draws a pixmap at (x,y) by copying a part of pixmap into
the paint device.
(x,y) specify the top-left point in the paint device that
is to be drawn onto. (sx,sy) specify the top-left point in
pixmap that is to be drawn (the default is (0,0). (sw,sh)
specify the size of the pixmap that is to be drawn (the
default, (-1,-1), means all the way to the right/bottom of
the pixmap).
See also bitBlt() and QPixmap::setMask().
Examples: qtimage/qtimage.cpp grapher/grapher.cpp
qmag/qmag.cpp scrollview/scrollview.cpp movies/main.cpp
picture/picture.cpp
void QPainter::drawPixmap ( const QPoint & p, const QPixmap & pm
)
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
This version of the call draws the entire pixmap.
void QPainter::drawPixmap ( const QPoint & p, const QPixmap & pm,
const QRect & sr )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::drawPoint ( int x, int y )
Draws/plots a single point at (x,y) using the current pen.
See also QPen.
Examples: drawlines/connect.cpp desktop/desktop.cpp
void QPainter::drawPoint ( const QPoint & p )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::drawPoints ( const QPointArray & a, int index=0,
int npoints=-1 )
Draws/plots an array of points using the current pen.
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QPainter(3qt)QPainter(3qt)
If index is non-zero (the default is zero) only points
from index are drawn. If npoints is negative (the default)
the rest of the points from index are drawn. If is is zero
or greater, npoints points are drawn.
void QPainter::drawPolygon ( const QPointArray & a, bool
winding=FALSE, int index=0, int npoints=-1 )
Draws the polygon defined by the npoints points in a
starting at a[index]. (index defaults to 0.)
If npoints is -1 (the default) all points until the end of
the array are used (i.e. a.size()-index line segments
define the polygon).
The first point is always connected to the last point.
The polygon is filled with the current brush(). If winding
is TRUE, the polygon is filled using the winding fill
algorithm. If winding is FALSE, the polygon is filled
using the even-odd (alternative) fill algorithm.
See also drawLineSegments(), drawPolyline() and QPen.
Examples: desktop/desktop.cpp picture/picture.cpp
void QPainter::drawPolyline ( const QPointArray & a, int index=0,
int npoints=-1 )
Draws the polyline defined by the npoints points in a
starting at a[index]. (index defaults to 0.)
If npoints is -1 (the default) all points until the end of
the array are used (i.e. a.size()-index-1 line segments
are drawn).
See also drawLineSegments(), drawPolygon() and QPen.
void QPainter::drawQuadBezier ( const QPointArray & a, int
index=0 )
Draws a cubic Bezier curve defined by the control points
in a, starting at a[index]. (index defaults to 0.)
Control points after a[index+3] are ignored. Nothing
happens if there aren't enough control points.
void QPainter::drawRect ( int x, int y, int w, int h )
Draws a rectangle with upper left corner at (x,y) and with
width w and height h.
See also QPen and drawRoundRect().
Examples: grapher/grapher.cpp drawdemo/drawdemo.cpp
forever/forever.cpp trivial/trivial.cpp
picture/picture.cpp
Trolltech AS 13 June 2001 15
QPainter(3qt)QPainter(3qt)void QPainter::drawRect ( 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.
void QPainter::drawRoundRect ( int x, int y, int w, int h, int
xRnd, int yRnd )
Draws a rectangle with round corners at (x,y), with width
w and height h.
The xRnd and yRnd arguments specify how rounded the
corners should be. 0 is angled corners, 99 is maximum
roundedness.
The width and height include all of the drawn lines.
See also drawRect() and QPen.
Examples: drawdemo/drawdemo.cpp
void QPainter::drawRoundRect ( const QRect & r, int xRnd, int
yRnd )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::drawRoundRect ( const QRect & )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
As the main version of the function, but with the
roundness arguments fixed at 25.
void QPainter::drawRoundRect ( int x, int y, int w, int h )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
As the main version of the function, but with the
roundness arguments fixed at 25.
void QPainter::drawText ( int x, int y, const QString & str, int
len = -1 )
Draws at most len characters from str at position (x,y).
(x,y) is the base line position. Note that the meaning of
y is not the same for the two drawText() varieties.
void QPainter::drawText ( int x, int y, int w, int h, int tf,
const QString & str, int len = -1, QRect * brect=0, char
** internal=0 )
Draws at most len characters from str in the rectangle
(x,y,w,h).
Trolltech AS 13 June 2001 16
QPainter(3qt)QPainter(3qt)
Note that the meaning of y is not the same for the two
drawText() varieties.
This function draws formatted text. The tf text formatting
is really of type Qt::AlignmentFlags.
Horizontal alignment defaults to AlignLeft and vertical
alignment defaults to AlignTop.
brect (if non-null) is set to the actual bounding
rectangle of the output. internal is, yes, internal.
See also boundingRect().
Examples: grapher/grapher.cpp drawdemo/drawdemo.cpp
menu/menu.cpp progress/progress.cpp desktop/desktop.cpp
scrollview/scrollview.cpp trivial/trivial.cpp
movies/main.cpp picture/picture.cpp
void QPainter::drawText ( const QPoint & p, const QString &, int
len = -1 )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::drawText ( const QRect & r, int tf, const QString
&, int len = -1, QRect * br=0, char ** i=0 )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::drawTiledPixmap ( int x, int y, int w, int h,
const QPixmap & pixmap, int sx=0, int sy=0 )
Draws a tiled pixmap in the specified rectangle.
(x,y) specify the top-left point in the paint device that
is to be drawn onto. (sx,sy) specify the top-left point in
pixmap that is to be drawn (the default is (0,0).
Calling drawTiledPixmap() is similar to calling
drawPixmap() several times to fill (tile) an area with a
pixmap, but is potentially much more efficient depending
on the underlying window system.
See also drawPixmap().
void QPainter::drawTiledPixmap ( const QRect & r, const QPixmap &
pm )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::drawTiledPixmap ( const QRect & r, const QPixmap &
pm, const QPoint & sp )
Trolltech AS 13 June 2001 17
QPainter(3qt)QPainter(3qt)
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::drawWinFocusRect ( int x, int y, int w, int h )
Draws a Windows focus rectangle with upper left corner at
(x,y) and with width w and height h.
This function draws a stippled XOR rectangle that is used
to indicate keyboard focus (when QApplication::style() is
WindowStyle).
Warning: This function draws nothing if the coordinate
system has been rotated or sheared.
See also drawRect() and QApplication::style().
void QPainter::drawWinFocusRect ( int x, int y, int w, int h,
const QColor & bgColor )
Draws a Windows focus rectangle with upper left corner at
(x,y) and with width w and height h using a pen color that
contrasts with bgColor.
This function draws a stippled rectangle (XOR is not used)
that is used to indicate keyboard focus (when the
QApplication::style() is WindowStyle).
The pen color used to draw the rectangle is either white
or black depending on the color of bgColor (see
QColor::gray()).
Warning: This function draws nothing if the coordinate
system has been rotated or sheared.
See also drawRect() and QApplication::style().
void QPainter::drawWinFocusRect ( 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.
void QPainter::drawWinFocusRect ( const QRect & r, const QColor &
bgColor )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
bool QPainter::end ()
Ends painting. Any resources used while painting are
released.
Note that while you mostly don't need to call end(), the
destructor will do it, there is at least one common case,
namely double buffering.
Trolltech AS 13 June 2001 18
QPainter(3qt)QPainter(3qt)QPainter p( myPixmap, this )
// ...
p.end(); // stops drawing on myPixmap
p.begin( this );
p.drawPixmap( myPixmap );
Since you can't draw a QPixmap while it is being painted,
it is necessary to close the active painter.
See also begin() and isActive().
Examples: desktop/desktop.cpp picture/picture.cpp
void QPainter::eraseRect ( int x, int y, int w, int h )
Erases the area inside (x,y,w,h). Equivalent to fillRect(
x, y, w, h, backgroundColor() )
void QPainter::eraseRect ( 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.
void QPainter::fillRect ( int x, int y, int w, int h, const
QBrush & brush )
Fills the rectangle (x,y,w,h) with the brush.
You can specify a QColor as brush, since there is a QBrush
constructor that takes a QColor argument and creates a
solid pattern brush.
See also drawRect().
Examples: progress/progress.cpp scrollview/scrollview.cpp
void QPainter::fillRect ( const QRect & r, const QBrush & brush )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::flush ()
Flushes any buffered drawing operations.
const QFont & QPainter::font () const
Returns the currently set painter font.
See also setFont() and QFont.
QFontInfo QPainter::fontInfo () const
Returns the font info for the painter, if the painter is
active. It is not possible to obtain font information for
an inactive painter, so the return value is undefined if
the painter is not active.
See also fontMetrics() and isActive().
Trolltech AS 13 June 2001 19
QPainter(3qt)QPainter(3qt)QFontMetrics QPainter::fontMetrics () const
Returns the font metrics for the painter, if the painter
is active. It is not possible to obtain metrics for an
inactive painter, so the return value is undefined if the
painter is not active.
See also fontInfo() and isActive().
Examples: drawdemo/drawdemo.cpp desktop/desktop.cpp
scrollview/scrollview.cpp movies/main.cpp
bool QPainter::hasClipping () const
Returns TRUE if clipping has been set, otherwise FALSE.
See also setClipping().
bool QPainter::hasViewXForm () const
Returns TRUE if view transformation is enabled, otherwise
FALSE.
See also setViewXForm() and xForm().
bool QPainter::hasWorldXForm () const
Returns TRUE if world transformation is enabled, otherwise
FALSE.
See also setWorldXForm().
void QPainter::initialize () [static]
Internal function that initializes the painter.
bool QPainter::isActive () const
Returns TRUE if the painter is active painting, i.e.
begin() has been called and end() has not yet been called.
See also QPaintDevice::paintingActive().
Examples: desktop/desktop.cpp
void QPainter::lineTo ( int x, int y )
Draws a line from the current pen position to (x,y) and
sets (x,y) to be the new current pen position.
See also QPen, moveTo(), drawLine() and pos().
void QPainter::lineTo ( const QPoint & p )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::moveTo ( int x, int y )
Sets the current pen position to (x,y)
See also lineTo() and pos().
Trolltech AS 13 June 2001 20
QPainter(3qt)QPainter(3qt)void QPainter::moveTo ( const QPoint & p )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
const QPen & QPainter::pen () const
Returns the current pen for the painter.
See also setPen().
Examples: progress/progress.cpp
QPoint QPainter::pos () const
Returns the current position of the pen.
See also moveTo().
RasterOp QPainter::rasterOp () const
Returns the current raster operation.
See also setRasterOp() and RasterOp.
void QPainter::redirect ( QPaintDevice * pdev, QPaintDevice *
replacement ) [static]
Redirects all paint command for a paint device pdev to
another paint device replacement, unless replacement is 0.
If replacement is 0, the redirection for pdev is removed.
Mostly, you can get better results with less work by
calling QPixmap::grabWidget() or QPixmap::grapWindow().
void QPainter::resetXForm ()
Resets any transformations that were made using
translate(), scale(), shear(), rotate(), setWorldMatrix(),
setViewport() and setWindow()
See also worldMatrix(), viewport() and window().
void QPainter::restore ()
Restores the current painter state (pops a saved state off
the stack).
See also save().
void QPainter::restoreWorldMatrix ()
This function is obsolete. It is provided to keep old
source working, and will probably be removed in a future
version of Qt. We strongly advise against using it in new
code.
We recommend using save() instead.
void QPainter::rotate ( double a )
Rotates the coordinate system a degrees.
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QPainter(3qt)QPainter(3qt)
See also translate(), scale(), shear(), resetXForm(),
setWorldMatrix() and xForm().
void QPainter::save ()
Saves the current painter state (pushes the state onto a
stack). A save() must be followed by a corresponding
restore(). end() unwinds the stack().
See also restore().
void QPainter::saveWorldMatrix ()
This function is obsolete. It is provided to keep old
source working, and will probably be removed in a future
version of Qt. We strongly advise against using it in new
code.
We recommend using save() instead.
void QPainter::scale ( double sx, double sy )
Scales the coordinate system by (sx,sy).
See also translate(), shear(), rotate(), resetXForm(),
setWorldMatrix() and xForm().
void QPainter::setBackgroundColor ( const QColor & c )
Sets the background color of the painter to c.
The background color is the color that is filled in when
drawing opaque text, stippled lines and bitmaps. The
background color has no effect in transparent background
mode (which is the default).
See also backgroundColor(), setBackgroundMode() and
BackgroundMode.
void QPainter::setBackgroundMode ( BGMode m )
Sets the background mode of the painter to m, which must
be one of TransparentMode (the default) and OpaqueMode.
Transparent mode draws stippled lines and text without
setting the background pixels. Opaque mode fills these
space with the current background color.
Note that in order to draw a bitmap or pixmap
transparently, you must use QPixmap::setMask().
See also backgroundMode() and setBackgroundColor().
Examples: picture/picture.cpp
void QPainter::setBrush ( BrushStyle style )
Sets a new painter brush with black color and the
specified style.
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QPainter(3qt)QPainter(3qt)
See also brush() and QBrush.
void QPainter::setBrush ( const QBrush & brush )
Sets a new painter brush.
The brush defines how to fill shapes.
See also brush().
Examples: grapher/grapher.cpp drawdemo/drawdemo.cpp
forever/forever.cpp desktop/desktop.cpp
picture/picture.cpp
void QPainter::setBrush ( const QColor & color )
Sets a new painter brush with the style SolidPattern and
the specified color.
See also brush() and QBrush.
void QPainter::setBrushOrigin ( int x, int y )
Sets the brush origin to (x,y).
The brush origin specifies the (0,0) coordinate of the
painter's brush. This setting only applies to pattern
brushes and pixmap brushes.
See also brushOrigin().
void QPainter::setBrushOrigin ( const QPoint & p )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
void QPainter::setClipRect ( int x, int y, int w, int h )
Sets the clip region to the the rectangle (x,y,w,h) and
enables clipping.
Note that the clip region is given in physical device
coordinates and not subject to any coordinate
transformation.
See also setClipRegion(), clipRegion() and setClipping().
Examples: qtimage/qtimage.cpp grapher/grapher.cpp
progress/progress.cpp splitter/splitter.cpp
trivial/trivial.cpp
void QPainter::setClipRect ( 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.
If the rectangle is invalid, the rectangle will be
normalized() before the clipping region is set. This
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QPainter(3qt)QPainter(3qt)
semantics will change in Qt-3 and an invalid rectangle
will clip the painter to an empty rectangle.
See also QRect::isValid() and QRect::normalize().
void QPainter::setClipRegion ( const QRegion & rgn )
Sets the clip region to rgn and enables clipping.
Note that the clip region is given in physical device
coordinates and not subject to any coordinate
transformation.
See also setClipRect(), clipRegion() and setClipping().
void QPainter::setClipping ( bool enable )
Enables clipping if enable is TRUE, or disables clipping
if enable is FALSE.
See also hasClipping(), setClipRect() and setClipRegion().
void QPainter::setFont ( const QFont & font )
Sets a new painter font.
This font is used by subsequent drawText() functions. The
text color is the same as the pen color.
See also font() and drawText().
Examples: grapher/grapher.cpp drawdemo/drawdemo.cpp
menu/menu.cpp scrollview/scrollview.cpp movies/main.cpp
picture/picture.cpp
void QPainter::setPen ( PenStyle style )
Sets a new painter pen with style style, width 0 and black
color.
See also pen() and QPen.
Examples: grapher/grapher.cpp drawlines/connect.cpp
drawdemo/drawdemo.cpp progress/progress.cpp
forever/forever.cpp desktop/desktop.cpp
scrollview/scrollview.cpp movies/main.cpp
void QPainter::setPen ( const QColor & color )
Sets a new painter pen with style SolidLine, width 0 and
the specified color.
See also pen() and QPen.
void QPainter::setPen ( const QPen & pen )
Sets a new painter pen.
The pen defines how to draw lines and outlines, and it
also defines the text color.
Trolltech AS 13 June 2001 24
QPainter(3qt)QPainter(3qt)
See also pen().
void QPainter::setRasterOp ( RasterOp r )
Sets the raster operation to r. The default is CopyROP.
See also rasterOp().
void QPainter::setTabArray ( int * ta )
Sets the tab stop array to ta. This puts tab stops at
ta[0], ta[1] and so on. The array is null-terminated.
If both a tab array and a tab top size is set, the tab
array wins.
See also tabArray(), setTabStops(), drawText() and
fontMetrics().
void QPainter::setTabStops ( int ts )
Set the tab stop width to ts, ie. locates tab stops at ts,
2*ts, 3*ts and so on.
Tab stops are used when drawing formatted text with
ExpandTabs set. This fixed tab stop value is used only if
no tab array is set (which is the default case).
See also tabStops(), setTabArray(), drawText() and
fontMetrics().
void QPainter::setViewXForm ( bool enable )
Enables view transformations if enable is TRUE, or
disables view transformations if enable is FALSE.
See also hasViewXForm(), setWindow(), setViewport(),
setWorldMatrix(), setWorldXForm() and xForm().
void QPainter::setViewport ( int x, int y, int w, int h )
Sets the viewport rectangle view transformation for the
painter and enables view transformation.
The viewport rectangle is part of the view transformation.
The viewport specifies the device coordinate system. Its
sister, the window(), specifies the logical coordinate
system.
The default viewport rectangle is the same as the device's
rectangle. See the Coordinate System Overview for an
overview of coordinate transformation.
See also viewport(), setWindow(), setViewXForm(),
setWorldMatrix(), setWorldXForm() and xForm().
void QPainter::setViewport ( const QRect & r )
This is an overloaded member function, provided for
convenience. It differs from the above function only in
Trolltech AS 13 June 2001 25
QPainter(3qt)QPainter(3qt)
what argument(s) it accepts.
void QPainter::setWindow ( int x, int y, int w, int h )
Sets the window rectangle view transformation for the
painter and enables view transformation.
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.
The default window rectangle is the same as the device's
rectangle. See the Coordinate System Overview for an
overview of coordinate transformation.
See also window(), setViewport(), setViewXForm(),
setWorldMatrix() and setWorldXForm().
Examples: drawdemo/drawdemo.cpp
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.
void QPainter::setWorldMatrix ( const QWMatrix & m, bool
combine=FALSE )
Sets the world transformation matrix to m and enables
world transformation.
If combine is TRUE, then m is combined with the current
transformation matrix, otherwise m replaces the current
transformation matrix.
If m the identity matrix and combine 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.)
World transformations are applied after the view
transformations (i.e. window and viewport).
The following functions can transform the coordinate
system without using a QWMatrix:
translate()scale()shear()rotate()
They operate on the painter's worldMatrix() and are
Trolltech AS 13 June 2001 26
QPainter(3qt)QPainter(3qt)
implemented like this:
void QPainter::rotate( double a )
{
QWMatrix m;
m.rotate( a );
setWorldMatrix( m, TRUE );
}
Note that you should always use combine 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.
For a brief overview of coordinate transformation, see the
Coordinate System Overview.
See also worldMatrix(), setWorldXForm(), setWindow(),
setViewport(), setViewXForm(), xForm() and QWMatrix.
Examples: drawdemo/drawdemo.cpp
void QPainter::setWorldXForm ( bool enable )
Enables world transformations if enable is TRUE, or
disables world transformations if enable is FALSE. The
world transformation matrix is not changed.
See also setWorldMatrix(), setWindow(), setViewport(),
setViewXForm() and xForm().
void QPainter::shear ( double sh, double sv )
Shears the coordinate system (sh,sv).
See also translate(), scale(), rotate(), resetXForm(),
setWorldMatrix() and xForm().
int * QPainter::tabArray () const
Returns the currently set tab stop array.
See also setTabArray().
int QPainter::tabStops () const
Returns the tab stop setting.
See also setTabStops().
void QPainter::translate ( double dx, double dy )
Translates the coordinate system by (dx,dy).
For example, the following code draws a single vertical
line 20 pixels high.
void MyWidget::paintEvent()
{
Trolltech AS 13 June 2001 27
QPainter(3qt)QPainter(3qt)QPainter paint( this );
paint.drawLine(10,0,10,20);
paint.translate(100.0,100.0);
paint.drawLine(-90,-80,-90,-70);
}
See also scale(), shear(), rotate(), resetXForm(),
setWorldMatrix() and xForm().
QRect QPainter::viewport () const
Returns the viewport rectangle.
See also setViewport() and setViewXForm().
QRect QPainter::window () const
Returns the window rectangle.
See also setWindow() and setViewXForm().
const QWMatrix & QPainter::worldMatrix () const
Returns the world transformation matrix.
See also setWorldMatrix().
QPoint QPainter::xForm ( const QPoint & pv ) const
Returns the point pv transformed from model coordinates to
device coordinates.
See also xFormDev() and QWMatrix::map().
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.
Returns the point array av transformed from model
coordinates to device coordinates.
See also xFormDev() and QWMatrix::map().
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.
Returns the point array av transformed from model
coordinates to device coordinates. The index is the first
point in the array and npoints denotes the number of
points to be transformed. If npoints is negative, all
points from av[index] until the last point in the array
are transformed.
The returned point array consists of the number of points
Trolltech AS 13 June 2001 28
QPainter(3qt)QPainter(3qt)
that were transformed.
Example:
QPointArray a(10);
QPointArray b;
b = painter.xForm(a,2,4); // b.size() == 4
b = painter.xForm(a,2,-1); // b.size() == 8
See also xFormDev() and QWMatrix::map().
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.
Returns the rectangle rv transformed from model
coordinates to device coordinates.
If world transformation is enabled and rotation or
shearing has been specified, then the bounding rectangle
is returned.
See also xFormDev() and QWMatrix::map().
QPoint QPainter::xFormDev ( const QPoint & pd ) const
Returns the point pv transformed from device coordinates
to model coordinates.
See also xForm() and QWMatrix::map().
QPointArray QPainter::xFormDev ( const QPointArray & ad ) const
Returns the point array av transformed from device
coordinates to model coordinates.
See also xForm() and QWMatrix::map().
QRect QPainter::xFormDev ( const QRect & rd ) const
Returns the rectangle rv transformed from device
coordinates to model coordinates.
If world transformation is enabled and rotation or
shearing is used, then the bounding rectangle is returned.
See also xForm() and QWMatrix::map().
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.
Returns the point array ad transformed from device
coordinates to model coordinates. The index is the first
Trolltech AS 13 June 2001 29
QPainter(3qt)QPainter(3qt)
point in the array and npoints denotes the number of
points to be transformed. If npoints is negative, all
points from av[index] until the last point in the array
are transformed.
The returned point array consists of the number of points
that were transformed.
Example:
QPointArray a(10);
QPointArray b;
b = painter.xFormDev(a,1,3); // b.size() == 3
b = painter.xFormDev(a,1,-1); // b.size() == 9
See also xForm() and QWMatrix::map().
RELATED FUNCTION DOCUMENTATIONvoid qDrawPlainRect (QPainter * p, int x, int y, int w, int h,
const QColor & c, int lineWidth, const QBrush * fill)
#include <qdrawutil.h>
Draws a plain rectangle given by (x, y, w, h) using the
painter p.
The color argument c specifies the line color.
The lineWidth argument specifies the line width.
The rectangle interior is filled with the fill brush
unless fill is null.
If you want to use a QFrame widget instead, you can make
it display a plain rectangle, for example
QFrame::setFrameStyle( QFrame::Box | QFrame::Plain ).
Warning: 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.
See also qDrawShadeRect() and QStyle::drawRect().
void qDrawShadeLine (QPainter * p, int x1, int y1, int x2, int
y2, const QColorGroup & g, bool sunken, int lineWidth, int
midLineWidth)
#include <qdrawutil.h>
Draws a horizontal (y1 == y2) or vertical (x1 == x2)
shaded line using the painter p.
Nothing is drawn if y1 != y2 and x1 != x2 (i.e. the line
is neither horizontal nor vertical).
The color group argument g specifies the shading colors
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QPainter(3qt)QPainter(3qt)
(light, dark and middle colors).
The line appears sunken if sunken is TRUE, or raised if
sunken is FALSE.
The lineWidth argument specifies the line width for each
of the lines. It is not the total line width.
The midLineWidth argument specifies the width of a middle
line drawn in the QColorGroup::mid() color.
If you want to use a QFrame widget instead, you can make
it display a shaded line, for example
QFrame::setFrameStyle( QFrame::HLine | QFrame::Sunken ).
Warning: 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.
See also qDrawShadeRect(), qDrawShadePanel() and
QStyle::drawSeparator().
void qDrawWinButton (QPainter * p, int x, int y, int w, int h,
const QColorGroup & g, bool sunken, const QBrush * fill)
#include <qdrawutil.h>
Draws a Windows-style button given by (x, y, w, h) using
the painter p.
The color group argument g specifies the shading colors
(light, dark and middle colors).
The button appears sunken if sunken is TRUE, or raised if
sunken is FALSE.
The line width is 2 pixels.
The button interior is filled with the *fill brush unless
fill is null.
Warning: 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.
See also qDrawWinPanel() and QStyle::drawButton().
void qDrawWinPanel (QPainter * p, int x, int y, int w, int h,
const QColorGroup & g, bool sunken, const QBrush * fill)
#include <qdrawutil.h>
Draws a Windows-style panel given by (x, y, w, h) using
the painter p.
The color group argument g specifies the shading colors.
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QPainter(3qt)QPainter(3qt)
The panel appears sunken if sunken is TRUE, or raised if
sunken is FALSE.
The line width is 2 pixels.
The button interior is filled with the fill brush unless
fill is null.
If you want to use a QFrame widget instead, you can make
it display a shaded panel, for example
QFrame::setFrameStyle( QFrame::WinPanel | QFrame::Raised
).
Warning: 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.
See also qDrawShadePanel(), qDrawWinButton() and
QStyle::drawPanel().
void qDrawShadePanel (QPainter * p, int x, int y, int w, int h,
const QColorGroup & g, bool sunken, int lineWidth, const
QBrush * fill)
#include <qdrawutil.h>
Draws a shaded panel given by (x, y, w, h) using the
painter p.
The color group argument g specifies the shading colors
(light, dark and middle colors).
The panel appears sunken if sunken is TRUE, or raised if
sunken is FALSE.
The lineWidth argument specifies the line width.
The panel interior is filled with the fill brush unless
fill is null.
If you want to use a QFrame widget instead, you can make
it display a shaded panel, for example
QFrame::setFrameStyle( QFrame::Panel | QFrame::Sunken ).
Warning: 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.
See also qDrawWinPanel(), qDrawShadeLine(),
qDrawShadeRect() and QStyle::drawPanel().
void qDrawShadeRect (QPainter * p, int x, int y, int w, int h,
const QColorGroup & g, bool sunken, int lineWidth, int
midLineWidth, const QBrush * fill)
#include <qdrawutil.h>
Trolltech AS 13 June 2001 32
QPainter(3qt)QPainter(3qt)
Draws a shaded rectangle/box given by (x, y, w, h) using
the painter p.
The color group argument g specifies the shading colors
(light, dark and middle colors).
The rectangle appears sunken if sunken is TRUE, or raised
if sunken is FALSE.
The lineWidth argument specifies the line width for each
of the lines. It is not the total line width.
The midLineWidth argument specifies the width of a middle
line drawn in the QColorGroup::mid() color.
The rectangle interior is filled with the fill brush
unless fill is null.
If you want to use a QFrame widget instead, you can make
it display a shaded rectangle, for example
QFrame::setFrameStyle( QFrame::Box | QFrame::Raised ).
Warning: 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.
See also qDrawShadeLine(), qDrawShadePanel(),
qDrawPlainRect(), QStyle::drawRect() and
QStyle::drawRectStrong().
SEE ALSO
http://doc.trolltech.com/qpainter.html
http://www.trolltech.com/faq/tech.html
COPYRIGHT
Copyright 1992-2001 Trolltech AS,
http://www.trolltech.com. See the license file included
in the distribution for a complete license statement.
AUTHOR
Generated automatically from the source code.
BUGS
If you find a bug in Qt, please report it as described in
http://doc.trolltech.com/bughowto.html. Good bug reports
make our job much simpler. Thank you.
In case of content or formattting problems with this
manual page, please report them to qt-bugs@trolltech.com.
Please include the name of the manual page (qpainter.3qt)
and the Qt version (2.3.1).
Trolltech AS 13 June 2001 33
