Sources_For_Linux/Qwt/doc/man/man3/QwtPolarItem.3

.TH "QwtPolarItem" 3 "Fri Sep 19 2014" "Version 1.1.1" "Qwt Polar User's Guide" \" -*- nroff -*-
.ad l
.nh
.SH NAME
QwtPolarItem \- 
.PP
Base class for items on a polar plot\&.  

.SH SYNOPSIS
.br
.PP
.PP
\fC#include <qwt_polar_item\&.h>\fP
.PP
Inherited by \fBQwtPolarCurve\fP, \fBQwtPolarGrid\fP, \fBQwtPolarMarker\fP, and \fBQwtPolarSpectrogram\fP\&.
.SS "Public Types"

.in +1c
.ti -1c
.RI "enum \fBRttiValues\fP { \fBRtti_PolarItem\fP = 0, \fBRtti_PolarGrid\fP, \fBRtti_PolarMarker\fP, \fBRtti_PolarCurve\fP, \fBRtti_PolarSpectrogram\fP, \fBRtti_PolarUserItem\fP = 1000 }"
.br
.RI "\fIRuntime type information\&. \fP"
.ti -1c
.RI "enum \fBItemAttribute\fP { \fBLegend\fP = 0x01, \fBAutoScale\fP = 0x02 }"
.br
.RI "\fIPlot Item Attributes\&. \fP"
.ti -1c
.RI "enum \fBRenderHint\fP { \fBRenderAntialiased\fP = 0x01 }"
.br
.RI "\fIRender hints\&. \fP"
.ti -1c
.RI "typedef QFlags< \fBItemAttribute\fP > \fBItemAttributes\fP"
.br
.RI "\fIItem attributes\&. \fP"
.ti -1c
.RI "typedef QFlags< \fBRenderHint\fP > \fBRenderHints\fP"
.br
.RI "\fIItem attributes\&. \fP"
.in -1c
.SS "Public Member Functions"

.in +1c
.ti -1c
.RI "\fBQwtPolarItem\fP (const QwtText &\fBtitle\fP=QwtText())"
.br
.ti -1c
.RI "virtual \fB~QwtPolarItem\fP ()"
.br
.RI "\fIDestroy the \fBQwtPolarItem\fP\&. \fP"
.ti -1c
.RI "void \fBattach\fP (\fBQwtPolarPlot\fP *\fBplot\fP)"
.br
.RI "\fIAttach the item to a plot\&. \fP"
.ti -1c
.RI "void \fBdetach\fP ()"
.br
.RI "\fIThis method detaches a \fBQwtPolarItem\fP from the \fBQwtPolarPlot\fP it has been associated with\&. \fP"
.ti -1c
.RI "\fBQwtPolarPlot\fP * \fBplot\fP () const "
.br
.ti -1c
.RI "void \fBsetTitle\fP (const QString &\fBtitle\fP)"
.br
.ti -1c
.RI "void \fBsetTitle\fP (const QwtText &\fBtitle\fP)"
.br
.ti -1c
.RI "const QwtText & \fBtitle\fP () const "
.br
.ti -1c
.RI "virtual int \fBrtti\fP () const "
.br
.ti -1c
.RI "void \fBsetItemAttribute\fP (\fBItemAttribute\fP, bool on=true)"
.br
.ti -1c
.RI "bool \fBtestItemAttribute\fP (\fBItemAttribute\fP) const "
.br
.ti -1c
.RI "void \fBsetRenderHint\fP (\fBRenderHint\fP, bool on=true)"
.br
.ti -1c
.RI "bool \fBtestRenderHint\fP (\fBRenderHint\fP) const "
.br
.ti -1c
.RI "void \fBsetRenderThreadCount\fP (uint numThreads)"
.br
.ti -1c
.RI "uint \fBrenderThreadCount\fP () const "
.br
.ti -1c
.RI "double \fBz\fP () const "
.br
.ti -1c
.RI "void \fBsetZ\fP (double \fBz\fP)"
.br
.RI "\fISet the z value\&. \fP"
.ti -1c
.RI "void \fBshow\fP ()"
.br
.RI "\fIShow the item\&. \fP"
.ti -1c
.RI "void \fBhide\fP ()"
.br
.RI "\fIHide the item\&. \fP"
.ti -1c
.RI "virtual void \fBsetVisible\fP (bool)"
.br
.ti -1c
.RI "bool \fBisVisible\fP () const "
.br
.ti -1c
.RI "virtual void \fBitemChanged\fP ()"
.br
.ti -1c
.RI "virtual void \fBlegendChanged\fP ()"
.br
.ti -1c
.RI "virtual void \fBdraw\fP (QPainter *painter, const QwtScaleMap &azimuthMap, const QwtScaleMap &radialMap, const QPointF &pole, double radius, const QRectF &canvasRect) const =0"
.br
.RI "\fIDraw the item\&. \fP"
.ti -1c
.RI "virtual QwtInterval \fBboundingInterval\fP (int scaleId) const "
.br
.ti -1c
.RI "virtual void \fBupdateScaleDiv\fP (const QwtScaleDiv &, const QwtScaleDiv &, const QwtInterval &)"
.br
.RI "\fIUpdate the item to changes of the axes scale division\&. \fP"
.ti -1c
.RI "virtual int \fBmarginHint\fP () const "
.br
.ti -1c
.RI "void \fBsetLegendIconSize\fP (const QSize &)"
.br
.ti -1c
.RI "QSize \fBlegendIconSize\fP () const "
.br
.ti -1c
.RI "virtual QList< QwtLegendData > \fBlegendData\fP () const "
.br
.RI "\fIReturn all information, that is needed to represent the item on the legend\&. \fP"
.ti -1c
.RI "virtual QwtGraphic \fBlegendIcon\fP (int index, const QSizeF &) const "
.br
.in -1c
.SH "Detailed Description"
.PP 
Base class for items on a polar plot\&. 

A \fBQwtPolarItem\fP is 'something that can be painted on the canvas'\&. It is connected to the QwtPolar framework by a couple of virtual methods, that are individually implemented in derived item classes\&.
.PP
QwtPolar offers an implementation of the most common types of items, but deriving from \fBQwtPolarItem\fP makes it easy to implement additional types of items\&. 
.SH "Member Enumeration Documentation"
.PP 
.SS "enum \fBQwtPolarItem::ItemAttribute\fP"

.PP
Plot Item Attributes\&. 
.PP
\fBSee Also:\fP
.RS 4
\fBsetItemAttribute()\fP, \fBtestItemAttribute()\fP 
.RE
.PP

.PP
\fBEnumerator\fP
.in +1c
.TP
\fB\fILegend \fP\fP
The item is represented on the legend\&. 
.TP
\fB\fIAutoScale \fP\fP
The boundingRect() of the item is included in the autoscaling calculation\&. 
.SS "enum \fBQwtPolarItem::RenderHint\fP"

.PP
Render hints\&. 
.PP
\fBSee Also:\fP
.RS 4
\fBsetRenderHint()\fP, \fBtestRenderHint()\fP 
.RE
.PP

.PP
\fBEnumerator\fP
.in +1c
.TP
\fB\fIRenderAntialiased \fP\fP
Enable antialiasing\&. 
.SS "enum \fBQwtPolarItem::RttiValues\fP"

.PP
Runtime type information\&. RttiValues is used to cast plot items, without having to enable runtime type information of the compiler\&. 
.PP
\fBEnumerator\fP
.in +1c
.TP
\fB\fIRtti_PolarItem \fP\fP
Unspecific value, that can be used, when it doesn't matter\&. 
.TP
\fB\fIRtti_PolarGrid \fP\fP
For \fBQwtPolarGrid\fP\&. 
.TP
\fB\fIRtti_PolarMarker \fP\fP
For \fBQwtPolarMarker\fP\&. 
.TP
\fB\fIRtti_PolarCurve \fP\fP
For \fBQwtPolarCurve\fP\&. 
.TP
\fB\fIRtti_PolarSpectrogram \fP\fP
For \fBQwtPolarSpectrogram\fP\&. 
.TP
\fB\fIRtti_PolarUserItem \fP\fP
Values >= Rtti_PolarUserItem are reserved for plot items not implemented in the QwtPolar library\&. 
.SH "Constructor & Destructor Documentation"
.PP 
.SS "QwtPolarItem::QwtPolarItem (const QwtText &title = \fCQwtText()\fP)\fC [explicit]\fP"
Constructor
.PP
\fBParameters:\fP
.RS 4
\fItitle\fP Item title, f\&.e used on a legend
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBsetTitle()\fP 
.RE
.PP

.SH "Member Function Documentation"
.PP 
.SS "void QwtPolarItem::attach (\fBQwtPolarPlot\fP *plot)"

.PP
Attach the item to a plot\&. This method will attach a \fBQwtPolarItem\fP to the \fBQwtPolarPlot\fP argument\&. It will first detach the \fBQwtPolarItem\fP from any plot from a previous call to attach (if necessary)\&. If a NULL argument is passed, it will detach from any \fBQwtPolarPlot\fP it was attached to\&.
.PP
\fBParameters:\fP
.RS 4
\fIplot\fP Plot widget
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBQwtPolarItem::detach()\fP 
.RE
.PP

.SS "QwtInterval QwtPolarItem::boundingInterval (intscaleId) const\fC [virtual]\fP"
Interval, that is necessary to display the item
.PP
This interval can be useful for operations like clipping or autoscaling For items ( like the grid ), where a bounding interval makes no sense an invalid interval is returned\&.
.PP
\fBParameters:\fP
.RS 4
\fIscaleId\fP Scale id ( QwtPolar::Scale ) 
.RE
.PP
\fBReturns:\fP
.RS 4
Bounding interval of the plot item for a specific scale 
.RE
.PP

.PP
Reimplemented in \fBQwtPolarCurve\fP, \fBQwtPolarSpectrogram\fP, and \fBQwtPolarMarker\fP\&.
.SS "void QwtPolarItem::detach ()"

.PP
This method detaches a \fBQwtPolarItem\fP from the \fBQwtPolarPlot\fP it has been associated with\&. \fBdetach()\fP is equivalent to calling attach( NULL ) 
.PP
\fBSee Also:\fP
.RS 4
\fBattach()\fP 
.RE
.PP

.SS "virtual void QwtPolarItem::draw (QPainter *painter, const QwtScaleMap &azimuthMap, const QwtScaleMap &radialMap, const QPointF &pole, doubleradius, const QRectF &canvasRect) const\fC [pure virtual]\fP"

.PP
Draw the item\&. 
.PP
\fBParameters:\fP
.RS 4
\fIpainter\fP Painter 
.br
\fIazimuthMap\fP Maps azimuth values to values related to 0\&.0, M_2PI 
.br
\fIradialMap\fP Maps radius values into painter coordinates\&. 
.br
\fIpole\fP Position of the pole in painter coordinates 
.br
\fIradius\fP Radius of the complete plot area in painter coordinates 
.br
\fIcanvasRect\fP Contents rect of the canvas in painter coordinates 
.RE
.PP

.PP
Implemented in \fBQwtPolarGrid\fP, \fBQwtPolarCurve\fP, \fBQwtPolarSpectrogram\fP, and \fBQwtPolarMarker\fP\&.
.SS "bool QwtPolarItem::isVisible () const"

.PP
\fBReturns:\fP
.RS 4
true if visible 
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBsetVisible()\fP, \fBshow()\fP, \fBhide()\fP 
.RE
.PP

.SS "void QwtPolarItem::itemChanged ()\fC [virtual]\fP"
Update the legend and call \fBQwtPolarPlot::autoRefresh\fP for the parent plot\&.
.PP
\fBSee Also:\fP
.RS 4
updateLegend() 
.RE
.PP

.SS "void QwtPolarItem::legendChanged ()\fC [virtual]\fP"
Update the legend of the parent plot\&. 
.PP
\fBSee Also:\fP
.RS 4
\fBQwtPolarPlot::updateLegend()\fP, \fBitemChanged()\fP 
.RE
.PP

.SS "QList< QwtLegendData > QwtPolarItem::legendData () const\fC [virtual]\fP"

.PP
Return all information, that is needed to represent the item on the legend\&. Most items are represented by one entry on the legend showing an icon and a text\&.
.PP
QwtLegendData is basically a list of QVariants that makes it possible to overload and reimplement \fBlegendData()\fP to return almost any type of information, that is understood by the receiver that acts as the legend\&.
.PP
The default implementation returns one entry with the \fBtitle()\fP of the item and the \fBlegendIcon()\fP\&.
.PP
\fBSee Also:\fP
.RS 4
\fBtitle()\fP, \fBlegendIcon()\fP, QwtLegend 
.RE
.PP

.SS "QwtGraphic QwtPolarItem::legendIcon (intindex, const QSizeF &size) const\fC [virtual]\fP"

.PP
\fBReturns:\fP
.RS 4
Icon representing the item on the legend
.RE
.PP
The default implementation returns an invalid icon
.PP
\fBParameters:\fP
.RS 4
\fIindex\fP Index of the legend entry ( usually there is only one ) 
.br
\fIsize\fP Icon size
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBsetLegendIconSize()\fP, \fBlegendData()\fP 
.RE
.PP

.PP
Reimplemented in \fBQwtPolarCurve\fP\&.
.SS "QSize QwtPolarItem::legendIconSize () const"

.PP
\fBReturns:\fP
.RS 4
Legend icon size 
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBsetLegendIconSize()\fP, \fBlegendIcon()\fP 
.RE
.PP

.SS "int QwtPolarItem::marginHint () const\fC [virtual]\fP"
Some items like to display something (f\&.e\&. the azimuth axis) outside of the area of the interval of the radial scale\&. The default implementation returns 0 pixels
.PP
\fBReturns:\fP
.RS 4
Hint for the margin 
.RE
.PP

.PP
Reimplemented in \fBQwtPolarGrid\fP\&.
.SS "\fBQwtPolarPlot\fP * QwtPolarItem::plot () const"

.PP
\fBReturns:\fP
.RS 4
Attached plot 
.RE
.PP

.SS "uint QwtPolarItem::renderThreadCount () const"

.PP
\fBReturns:\fP
.RS 4
Number of threads to be used for rendering\&. If numThreads() is set to 0, the system specific ideal thread count is used\&. 
.RE
.PP

.SS "int QwtPolarItem::rtti () const\fC [virtual]\fP"
Return rtti for the specific class represented\&. \fBQwtPolarItem\fP is simply a virtual interface class, and base classes will implement this method with specific rtti values so a user can differentiate them\&.
.PP
The rtti value is useful for environments, where the runtime type information is disabled and it is not possible to do a dynamic_cast<\&.\&.\&.>\&.
.PP
\fBReturns:\fP
.RS 4
rtti value 
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBRttiValues\fP 
.RE
.PP

.PP
Reimplemented in \fBQwtPolarGrid\fP, \fBQwtPolarCurve\fP, \fBQwtPolarSpectrogram\fP, and \fBQwtPolarMarker\fP\&.
.SS "void QwtPolarItem::setItemAttribute (\fBItemAttribute\fPattribute, boolon = \fCtrue\fP)"
Toggle an item attribute
.PP
\fBParameters:\fP
.RS 4
\fIattribute\fP Attribute type 
.br
\fIon\fP true/false
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBtestItemAttribute()\fP, \fBItemAttribute\fP 
.RE
.PP

.SS "void QwtPolarItem::setLegendIconSize (const QSize &size)"
Set the size of the legend icon
.PP
The default setting is 8x8 pixels
.PP
\fBParameters:\fP
.RS 4
\fIsize\fP Size 
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBlegendIconSize()\fP, \fBlegendIcon()\fP 
.RE
.PP

.SS "void QwtPolarItem::setRenderHint (\fBRenderHint\fPhint, boolon = \fCtrue\fP)"
Toggle an render hint
.PP
\fBParameters:\fP
.RS 4
\fIhint\fP Render hint 
.br
\fIon\fP true/false
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBtestRenderHint()\fP, \fBRenderHint\fP 
.RE
.PP

.SS "void QwtPolarItem::setRenderThreadCount (uintnumThreads)"
On multi core systems rendering of certain plot item ( f\&.e \fBQwtPolarSpectrogram\fP ) can be done in parallel in several threads\&.
.PP
The default setting is set to 1\&.
.PP
\fBParameters:\fP
.RS 4
\fInumThreads\fP Number of threads to be used for rendering\&. If numThreads is set to 0, the system specific ideal thread count is used\&.
.RE
.PP
The default thread count is 1 ( = no additional threads ) 
.SS "void QwtPolarItem::setTitle (const QString &title)"
Set a new title
.PP
\fBParameters:\fP
.RS 4
\fItitle\fP Title 
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBtitle()\fP 
.RE
.PP

.SS "void QwtPolarItem::setTitle (const QwtText &title)"
Set a new title
.PP
\fBParameters:\fP
.RS 4
\fItitle\fP Title 
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBtitle()\fP 
.RE
.PP

.SS "void QwtPolarItem::setVisible (boolon)\fC [virtual]\fP"
Show/Hide the item
.PP
\fBParameters:\fP
.RS 4
\fIon\fP Show if true, otherwise hide 
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBisVisible()\fP, \fBshow()\fP, \fBhide()\fP 
.RE
.PP

.SS "void QwtPolarItem::setZ (doublez)"

.PP
Set the z value\&. Plot items are painted in increasing z-order\&.
.PP
\fBParameters:\fP
.RS 4
\fIz\fP Z-value 
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBz()\fP, \fBQwtPolarItemDict::itemList()\fP 
.RE
.PP

.SS "bool QwtPolarItem::testItemAttribute (\fBItemAttribute\fPattribute) const"
Test an item attribute
.PP
\fBParameters:\fP
.RS 4
\fIattribute\fP Attribute type 
.RE
.PP
\fBReturns:\fP
.RS 4
true/false 
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBsetItemAttribute()\fP, \fBItemAttribute\fP 
.RE
.PP

.SS "bool QwtPolarItem::testRenderHint (\fBRenderHint\fPhint) const"
Test a render hint
.PP
\fBParameters:\fP
.RS 4
\fIhint\fP Render hint 
.RE
.PP
\fBReturns:\fP
.RS 4
true/false 
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBsetRenderHint()\fP, \fBRenderHint\fP 
.RE
.PP

.SS "const QwtText & QwtPolarItem::title () const"

.PP
\fBReturns:\fP
.RS 4
Title of the item 
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBsetTitle()\fP 
.RE
.PP

.SS "void QwtPolarItem::updateScaleDiv (const QwtScaleDiv &azimuthScaleDiv, const QwtScaleDiv &radialScaleDiv, const QwtInterval &interval)\fC [virtual]\fP"

.PP
Update the item to changes of the axes scale division\&. Update the item, when the axes of plot have changed\&. The default implementation does nothing, but items that depend on the scale division (like \fBQwtPolarGrid()\fP) have to reimplement \fBupdateScaleDiv()\fP
.PP
\fBParameters:\fP
.RS 4
\fIazimuthScaleDiv\fP Scale division of the azimuth-scale 
.br
\fIradialScaleDiv\fP Scale division of the radius-axis 
.br
\fIinterval\fP The interval of the radius-axis, that is visible on the canvas
.RE
.PP
\fBSee Also:\fP
.RS 4
QwtPolarPlot::updateAxes() 
.RE
.PP

.PP
Reimplemented in \fBQwtPolarGrid\fP\&.
.SS "double QwtPolarItem::z () const"
Plot items are painted in increasing z-order\&.
.PP
\fBReturns:\fP
.RS 4
Z value 
.RE
.PP
\fBSee Also:\fP
.RS 4
\fBsetZ()\fP, \fBQwtPolarItemDict::itemList()\fP 
.RE
.PP


.SH "Author"
.PP 
Generated automatically by Doxygen for Qwt Polar User's Guide from the source code\&.