1 /* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
2 * Qwt Widget Library
3 * Copyright (C) 1997 Josef Wilgen
4 * Copyright (C) 2002 Uwe Rathmann
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the Qwt License, Version 1.0
8 *****************************************************************************/
9
10 #ifndef QWT_PLOT_CURVE_H
11 #define QWT_PLOT_CURVE_H
12
13 #include "qwt_global.h"
14 #include "qwt_plot_seriesitem.h"
15 #include "qwt_series_data.h"
16 #include "qwt_text.h"
17 #include <qpen.h>
18 #include <qstring.h>
19
20 class QPainter;
21 class QPolygonF;
22 class QwtScaleMap;
23 class QwtSymbol;
24 class QwtCurveFitter;
25
26 /*!
27 \brief A plot item, that represents a series of points
28
29 A curve is the representation of a series of points in the x-y plane.
30 It supports different display styles, interpolation ( f.e. spline )
31 and symbols.
32
33 \par Usage
34 <dl><dt>a) Assign curve properties</dt>
35 <dd>When a curve is created, it is configured to draw black solid lines
36 with in QwtPlotCurve::Lines style and no symbols.
37 You can change this by calling
38 setPen(), setStyle() and setSymbol().</dd>
39 <dt>b) Connect/Assign data.</dt>
40 <dd>QwtPlotCurve gets its points using a QwtSeriesData object offering
41 a bridge to the real storage of the points ( like QAbstractItemModel ).
42 There are several convenience classes derived from QwtSeriesData, that also store
43 the points inside ( like QStandardItemModel ). QwtPlotCurve also offers
44 a couple of variations of setSamples(), that build QwtSeriesData objects from
45 arrays internally.</dd>
46 <dt>c) Attach the curve to a plot</dt>
47 <dd>See QwtPlotItem::attach()
48 </dd></dl>
49
50 \par Example:
51 see examples/bode
52
53 \sa QwtPointSeriesData, QwtSymbol, QwtScaleMap
54 */
55 class QWT_EXPORT QwtPlotCurve:
56 public QwtPlotSeriesItem, public QwtSeriesStore<QPointF>
57 {
58 public:
59 /*!
60 Curve styles.
61 \sa setStyle(), style()
62 */
63 enum CurveStyle
64 {
65 /*!
66 Don't draw a curve. Note: This doesn't affect the symbols.
67 */
68 NoCurve = -1,
69
70 /*!
71 Connect the points with straight lines. The lines might
72 be interpolated depending on the 'Fitted' attribute. Curve
73 fitting can be configured using setCurveFitter().
74 */
75 Lines,
76
77 /*!
78 Draw vertical or horizontal sticks ( depending on the
79 orientation() ) from a baseline which is defined by setBaseline().
80 */
81 Sticks,
82
83 /*!
84 Connect the points with a step function. The step function
85 is drawn from the left to the right or vice versa,
86 depending on the QwtPlotCurve::Inverted attribute.
87 */
88 Steps,
89
90 /*!
91 Draw dots at the locations of the data points. Note:
92 This is different from a dotted line (see setPen()), and faster
93 as a curve in QwtPlotCurve::NoStyle style and a symbol
94 painting a point.
95 */
96 Dots,
97
98 /*!
99 Styles >= QwtPlotCurve::UserCurve are reserved for derived
100 classes of QwtPlotCurve that overload drawCurve() with
101 additional application specific curve types.
102 */
103 UserCurve = 100
104 };
105
106 /*!
107 Attribute for drawing the curve
108 \sa setCurveAttribute(), testCurveAttribute(), curveFitter()
109 */
110 enum CurveAttribute
111 {
112 /*!
113 For QwtPlotCurve::Steps only.
114 Draws a step function from the right to the left.
115 */
116 Inverted = 0x01,
117
118 /*!
119 Only in combination with QwtPlotCurve::Lines
120 A QwtCurveFitter tries to
121 interpolate/smooth the curve, before it is painted.
122
123 \note Curve fitting requires temporary memory
124 for calculating coefficients and additional points.
125 If painting in QwtPlotCurve::Fitted mode is slow it might be better
126 to fit the points, before they are passed to QwtPlotCurve.
127 */
128 Fitted = 0x02
129 };
130
131 //! Curve attributes
132 typedef QFlags<CurveAttribute> CurveAttributes;
133
134 /*!
135 Attributes how to represent the curve on the legend
136
137 \sa setLegendAttribute(), testLegendAttribute(),
138 QwtPlotItem::legendData(), legendIcon()
139 */
140
141 enum LegendAttribute
142 {
143 /*!
144 QwtPlotCurve tries to find a color representing the curve
145 and paints a rectangle with it.
146 */
147 LegendNoAttribute = 0x00,
148
149 /*!
150 If the style() is not QwtPlotCurve::NoCurve a line
151 is painted with the curve pen().
152 */
153 LegendShowLine = 0x01,
154
155 /*!
156 If the curve has a valid symbol it is painted.
157 */
158 LegendShowSymbol = 0x02,
159
160 /*!
161 If the curve has a brush a rectangle filled with the
162 curve brush() is painted.
163 */
164 LegendShowBrush = 0x04
165 };
166
167 //! Legend attributes
168 typedef QFlags<LegendAttribute> LegendAttributes;
169
170 /*!
171 Attributes to modify the drawing algorithm.
172 The default setting enables ClipPolygons | FilterPoints
173
174 \sa setPaintAttribute(), testPaintAttribute()
175 */
176 enum PaintAttribute
177 {
178 /*!
179 Clip polygons before painting them. In situations, where points
180 are far outside the visible area (f.e when zooming deep) this
181 might be a substantial improvement for the painting performance
182 */
183 ClipPolygons = 0x01,
184
185 /*!
186 Tries to reduce the data that has to be painted, by sorting out
187 duplicates, or paintings outside the visible area. Might have a
188 notable impact on curves with many close points.
189 Only a couple of very basic filtering algorithms are implemented.
190 */
191 FilterPoints = 0x02,
192
193 /*!
194 Minimize memory usage that is temporarily needed for the
195 translated points, before they get painted.
196 This might slow down the performance of painting
197 */
198 MinimizeMemory = 0x04,
199
200 /*!
201 Render the points to a temporary image and paint the image.
202 This is a very special optimization for Dots style, when
203 having a huge amount of points.
204 With a reasonable number of points QPainter::drawPoints()
205 will be faster.
206 */
207 ImageBuffer = 0x08
208 };
209
210 //! Paint attributes
211 typedef QFlags<PaintAttribute> PaintAttributes;
212
213 explicit QwtPlotCurve( const QString &title = QString() );
214 explicit QwtPlotCurve( const QwtText &title );
215
216 virtual ~QwtPlotCurve();
217
218 virtual int rtti() const;
219
220 void setPaintAttribute( PaintAttribute, bool on = true );
221 bool testPaintAttribute( PaintAttribute ) const;
222
223 void setLegendAttribute( LegendAttribute, bool on = true );
224 bool testLegendAttribute( LegendAttribute ) const;
225
226 #ifndef QWT_NO_COMPAT
227 void setRawSamples( const double *xData, const double *yData, int size );
228 void setSamples( const double *xData, const double *yData, int size );
229 void setSamples( const QVector<double> &xData, const QVector<double> &yData );
230 #endif
231 void setSamples( const QVector<QPointF> & );
232 void setSamples( QwtSeriesData<QPointF> * );
233
234 int closestPoint( const QPoint &pos, double *dist = NULL ) const;
235
236 double minXValue() const;
237 double maxXValue() const;
238 double minYValue() const;
239 double maxYValue() const;
240
241 void setCurveAttribute( CurveAttribute, bool on = true );
242 bool testCurveAttribute( CurveAttribute ) const;
243
244 void setPen( const QColor &, qreal width = 0.0, Qt::PenStyle = Qt::SolidLine );
245 void setPen( const QPen & );
246 const QPen &pen() const;
247
248 void setBrush( const QBrush & );
249 const QBrush &brush() const;
250
251 void setBaseline( double );
252 double baseline() const;
253
254 void setStyle( CurveStyle style );
255 CurveStyle style() const;
256
257 void setSymbol( QwtSymbol * );
258 const QwtSymbol *symbol() const;
259
260 void setCurveFitter( QwtCurveFitter * );
261 QwtCurveFitter *curveFitter() const;
262
263 virtual void drawSeries( QPainter *,
264 const QwtScaleMap &xMap, const QwtScaleMap &yMap,
265 const QRectF &canvasRect, int from, int to ) const;
266
267 virtual QwtGraphic legendIcon( int index, const QSizeF & ) const;
268
269 protected:
270
271 void init();
272
273 virtual void drawCurve( QPainter *, int style,
274 const QwtScaleMap &xMap, const QwtScaleMap &yMap,
275 const QRectF &canvasRect, int from, int to ) const;
276
277 virtual void drawSymbols( QPainter *, const QwtSymbol &,
278 const QwtScaleMap &xMap, const QwtScaleMap &yMap,
279 const QRectF &canvasRect, int from, int to ) const;
280
281 virtual void drawLines( QPainter *,
282 const QwtScaleMap &xMap, const QwtScaleMap &yMap,
283 const QRectF &canvasRect, int from, int to ) const;
284
285 virtual void drawSticks( QPainter *,
286 const QwtScaleMap &xMap, const QwtScaleMap &yMap,
287 const QRectF &canvasRect, int from, int to ) const;
288
289 virtual void drawDots( QPainter *,
290 const QwtScaleMap &xMap, const QwtScaleMap &yMap,
291 const QRectF &canvasRect, int from, int to ) const;
292
293 virtual void drawSteps( QPainter *,
294 const QwtScaleMap &xMap, const QwtScaleMap &yMap,
295 const QRectF &canvasRect, int from, int to ) const;
296
297 virtual void fillCurve( QPainter *,
298 const QwtScaleMap &, const QwtScaleMap &,
299 const QRectF &canvasRect, QPolygonF & ) const;
300
301 void closePolyline( QPainter *,
302 const QwtScaleMap &, const QwtScaleMap &, QPolygonF & ) const;
303
304 private:
305 class PrivateData;
306 PrivateData *d_data;
307 };
308
309 //! boundingRect().left()
minXValue()310 inline double QwtPlotCurve::minXValue() const
311 {
312 return boundingRect().left();
313 }
314
315 //! boundingRect().right()
maxXValue()316 inline double QwtPlotCurve::maxXValue() const
317 {
318 return boundingRect().right();
319 }
320
321 //! boundingRect().top()
minYValue()322 inline double QwtPlotCurve::minYValue() const
323 {
324 return boundingRect().top();
325 }
326
327 //! boundingRect().bottom()
maxYValue()328 inline double QwtPlotCurve::maxYValue() const
329 {
330 return boundingRect().bottom();
331 }
332
333 Q_DECLARE_OPERATORS_FOR_FLAGS( QwtPlotCurve::PaintAttributes )
334 Q_DECLARE_OPERATORS_FOR_FLAGS( QwtPlotCurve::LegendAttributes )
335 Q_DECLARE_OPERATORS_FOR_FLAGS( QwtPlotCurve::CurveAttributes )
336
337 #endif
338