QwtPolarItem(3) Qwt User's Guide QwtPolarItem(3) NAME QwtPolarItem - Base class for items on a polar plot. SYNOPSIS #include Inherited by QwtPolarCurve, QwtPolarGrid, QwtPolarMarker, and QwtPolarSpectrogram. Public Types enum RttiValues { Rtti_PolarItem = 0, Rtti_PolarGrid, Rtti_PolarMarker, Rtti_PolarCurve, Rtti_PolarSpectrogram, Rtti_PolarUserItem = 1000 } Runtime type information. enum ItemAttribute { Legend = 0x01, AutoScale = 0x02 } Plot Item Attributes. enum RenderHint { RenderAntialiased = 0x01 } Render hints. typedef QFlags< ItemAttribute > ItemAttributes typedef QFlags< RenderHint > RenderHints Public Member Functions QwtPolarItem (const QwtText &title=QwtText()) virtual ~QwtPolarItem () Destroy the QwtPolarItem. void attach (QwtPolarPlot *plot) Attach the item to a plot. void detach () This method detaches a QwtPolarItem from the QwtPolarPlot it has been associated with. QwtPolarPlot * plot () const void setTitle (const QString &title) void setTitle (const QwtText &title) const QwtText & title () const virtual int rtti () const void setItemAttribute (ItemAttribute, bool on=true) bool testItemAttribute (ItemAttribute) const void setRenderHint (RenderHint, bool on=true) bool testRenderHint (RenderHint) const void setRenderThreadCount (uint numThreads) uint renderThreadCount () const double z () const void setZ (double z) Set the z value. void show () Show the item. void hide () Hide the item. virtual void setVisible (bool) bool isVisible () const virtual void itemChanged () virtual void legendChanged () virtual void draw (QPainter *painter, const QwtScaleMap &azimuthMap, const QwtScaleMap &radialMap, const QPointF &pole, double radius, const QRectF &canvasRect) const =0 Draw the item. virtual QwtInterval boundingInterval (int scaleId) const virtual void updateScaleDiv (const QwtScaleDiv &, const QwtScaleDiv &, const QwtInterval &) Update the item to changes of the axes scale division. virtual int marginHint () const void setLegendIconSize (const QSize &) QSize legendIconSize () const virtual QList< QwtLegendData > legendData () const Return all information, that is needed to represent the item on the legend. virtual QwtGraphic legendIcon (int index, const QSizeF &) const Detailed Description Base class for items on a polar plot. A QwtPolarItem 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. QwtPolar offers an implementation of the most common types of items, but deriving from QwtPolarItem makes it easy to implement additional types of items. Definition at line 37 of file qwt_polar_item.h. Member Typedef Documentation typedef QFlags QwtPolarItem::ItemAttributes An ORed combination of ItemAttribute values. Definition at line 86 of file qwt_polar_item.h. typedef QFlags QwtPolarItem::RenderHints An ORed combination of RenderHint values. Definition at line 98 of file qwt_polar_item.h. Member Enumeration Documentation enum QwtPolarItem::ItemAttribute Plot Item Attributes. See also setItemAttribute(), testItemAttribute() Enumerator Legend The item is represented on the legend. AutoScale The boundingRect() of the item is included in the autoscaling calculation. Definition at line 74 of file qwt_polar_item.h. enum QwtPolarItem::RenderHint Render hints. See also setRenderHint(), testRenderHint() Enumerator RenderAntialiased Enable antialiasing. Definition at line 92 of file qwt_polar_item.h. enum QwtPolarItem::RttiValues Runtime type information. RttiValues is used to cast plot items, without having to enable runtime type information of the compiler. Enumerator Rtti_PolarItem Unspecific value, that can be used, when it doesn't matter. Rtti_PolarGrid For QwtPolarGrid. Rtti_PolarMarker For QwtPolarMarker. Rtti_PolarCurve For QwtPolarCurve. Rtti_PolarSpectrogram For QwtPolarSpectrogram. Rtti_PolarUserItem Values >= Rtti_PolarUserItem are reserved for plot items not implemented in the QwtPolar library. Definition at line 46 of file qwt_polar_item.h. Constructor & Destructor Documentation QwtPolarItem::QwtPolarItem (const QwtText & title = QwtText()) [explicit] Constructor Parameters title Item title, f.e used on a legend See also setTitle() Definition at line 48 of file qwt_polar_item.cpp. Member Function Documentation void QwtPolarItem::attach (QwtPolarPlot * plot) Attach the item to a plot. This method will attach a QwtPolarItem to the QwtPolarPlot argument. It will first detach the QwtPolarItem from any plot from a previous call to attach (if necessary). If a NULL argument is passed, it will detach from any QwtPolarPlot it was attached to. Parameters plot Plot widget See also QwtPolarItem::detach() Definition at line 74 of file qwt_polar_item.cpp. QwtInterval QwtPolarItem::boundingInterval (int scaleId) const [virtual] Interval, that is necessary to display the item 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. Parameters scaleId Scale id ( QwtPolar::Scale ) Returns Bounding interval of the plot item for a specific scale Reimplemented in QwtPolarSpectrogram, QwtPolarMarker, and QwtPolarCurve. Definition at line 381 of file qwt_polar_item.cpp. void QwtPolarItem::detach () This method detaches a QwtPolarItem from the QwtPolarPlot it has been associated with. detach() is equivalent to calling attach( NULL ) See also attach() Definition at line 95 of file qwt_polar_item.cpp. virtual void QwtPolarItem::draw (QPainter * painter, const QwtScaleMap & azimuthMap, const QwtScaleMap & radialMap, const QPointF & pole, double radius, const QRectF & canvasRect) const [pure virtual] Draw the item. Parameters painter Painter azimuthMap Maps azimuth values to values related to 0.0, M_2PI radialMap Maps radius values into painter coordinates. pole Position of the pole in painter coordinates radius Radius of the complete plot area in painter coordinates canvasRect Contents rect of the canvas in painter coordinates Implemented in QwtPolarSpectrogram, QwtPolarMarker, QwtPolarGrid, and QwtPolarCurve. bool QwtPolarItem::isVisible () const Returns true if visible See also setVisible(), show(), hide() Definition at line 344 of file qwt_polar_item.cpp. void QwtPolarItem::itemChanged () [virtual] Update the legend and call QwtPolarPlot::autoRefresh for the parent plot. See also updateLegend() Definition at line 355 of file qwt_polar_item.cpp. void QwtPolarItem::legendChanged () [virtual] Update the legend of the parent plot. See also QwtPolarPlot::updateLegend(), itemChanged() Definition at line 365 of file qwt_polar_item.cpp. QList< QwtLegendData > QwtPolarItem::legendData () const [virtual] 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. QwtLegendData is basically a list of QVariants that makes it possible to overload and reimplement legendData() to return almost any type of information, that is understood by the receiver that acts as the legend. The default implementation returns one entry with the title() of the item and the legendIcon(). See also title(), legendIcon(), QwtLegend Definition at line 428 of file qwt_polar_item.cpp. QwtGraphic QwtPolarItem::legendIcon (int index, const QSizeF & size) const [virtual] Returns Icon representing the item on the legend The default implementation returns an invalid icon Parameters index Index of the legend entry ( usually there is only one ) size Icon size See also setLegendIconSize(), legendData() Reimplemented in QwtPolarCurve. Definition at line 462 of file qwt_polar_item.cpp. QSize QwtPolarItem::legendIconSize () const Returns Legend icon size See also setLegendIconSize(), legendIcon() Definition at line 308 of file qwt_polar_item.cpp. int QwtPolarItem::marginHint () const [virtual] 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 Returns Hint for the margin Reimplemented in QwtPolarGrid. Definition at line 478 of file qwt_polar_item.cpp. QwtPolarPlot * QwtPolarItem::plot () const Returns Attached plot Definition at line 118 of file qwt_polar_item.cpp. uint QwtPolarItem::renderThreadCount () const Returns Number of threads to be used for rendering. If numThreads() is set to 0, the system specific ideal thread count is used. Definition at line 282 of file qwt_polar_item.cpp. int QwtPolarItem::rtti () const [virtual] Return rtti for the specific class represented. QwtPolarItem is simply a virtual interface class, and base classes will implement this method with specific rtti values so a user can differentiate them. The rtti value is useful for environments, where the runtime type information is disabled and it is not possible to do a dynamic_cast<...>. Returns rtti value See also RttiValues Reimplemented in QwtPolarSpectrogram, QwtPolarMarker, QwtPolarGrid, and QwtPolarCurve. Definition at line 112 of file qwt_polar_item.cpp. void QwtPolarItem::setItemAttribute (ItemAttribute attribute, bool on = true) Toggle an item attribute Parameters attribute Attribute type on true/false See also testItemAttribute(), ItemAttribute Definition at line 201 of file qwt_polar_item.cpp. void QwtPolarItem::setLegendIconSize (const QSize & size) Set the size of the legend icon The default setting is 8x8 pixels Parameters size Size See also legendIconSize(), legendIcon() Definition at line 295 of file qwt_polar_item.cpp. void QwtPolarItem::setRenderHint (RenderHint hint, bool on = true) Toggle an render hint Parameters hint Render hint on true/false See also testRenderHint(), RenderHint Definition at line 234 of file qwt_polar_item.cpp. void QwtPolarItem::setRenderThreadCount (uint numThreads) On multi core systems rendering of certain plot item ( f.e QwtPolarSpectrogram ) can be done in parallel in several threads. The default setting is set to 1. Parameters numThreads Number of threads to be used for rendering. If numThreads is set to 0, the system specific ideal thread count is used. The default thread count is 1 ( = no additional threads ) Definition at line 272 of file qwt_polar_item.cpp. void QwtPolarItem::setTitle (const QString & title) Set a new title Parameters title Title See also title() Definition at line 164 of file qwt_polar_item.cpp. void QwtPolarItem::setTitle (const QwtText & title) Set a new title Parameters title Title See also title() Definition at line 175 of file qwt_polar_item.cpp. void QwtPolarItem::setVisible (bool on) [virtual] Show/Hide the item Parameters on Show if true, otherwise hide See also isVisible(), show(), hide() Definition at line 331 of file qwt_polar_item.cpp. void QwtPolarItem::setZ (double z) Set the z value. Plot items are painted in increasing z-order. Parameters z Z-value See also z(), QwtPolarItemDict::itemList() Definition at line 142 of file qwt_polar_item.cpp. bool QwtPolarItem::testItemAttribute (ItemAttribute attribute) const Test an item attribute Parameters attribute Attribute type Returns true/false See also setItemAttribute(), ItemAttribute Definition at line 221 of file qwt_polar_item.cpp. bool QwtPolarItem::testRenderHint (RenderHint hint) const Test a render hint Parameters hint Render hint Returns true/false See also setRenderHint(), RenderHint Definition at line 254 of file qwt_polar_item.cpp. const QwtText & QwtPolarItem::title () const Returns Title of the item See also setTitle() Definition at line 188 of file qwt_polar_item.cpp. void QwtPolarItem::updateScaleDiv (const QwtScaleDiv & azimuthScaleDiv, const QwtScaleDiv & radialScaleDiv, const QwtInterval & interval) [virtual] 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 QwtPolarGrid()) have to reimplement updateScaleDiv() Parameters azimuthScaleDiv Scale division of the azimuth-scale radialScaleDiv Scale division of the radius-axis interval The interval of the radius-axis, that is visible on the canvas See also QwtPolarPlot::updateAxes() Reimplemented in QwtPolarGrid. Definition at line 403 of file qwt_polar_item.cpp. double QwtPolarItem::z () const Plot items are painted in increasing z-order. Returns Z value See also setZ(), QwtPolarItemDict::itemList() Definition at line 129 of file qwt_polar_item.cpp. Author Generated automatically by Doxygen for Qwt User's Guide from the source code. Version 6.2.0 Sun Jul 18 2021 QwtPolarItem(3)