File: class_qwt_raster_data.html

package info (click to toggle)
qwt5 5.2.2-3
  • links: PTS
  • area: main
  • in suites: wheezy
  • size: 13,340 kB
  • sloc: cpp: 32,645; makefile: 23; sh: 4
file content (419 lines) | stat: -rw-r--r-- 21,021 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
<title>Qwt User&#39;s Guide: QwtRasterData Class Reference</title>
<link href="tabs.css" rel="stylesheet" type="text/css"/>
<link href="doxygen.css" rel="stylesheet" type="text/css"/>
</head>
<body>
<!-- Generated by Doxygen 1.7.3 -->
<div id="top">
<div id="titlearea">
<table cellspacing="0" cellpadding="0">
 <tbody>
 <tr style="height: 56px;">
  <td style="padding-left: 0.5em;">
   <div id="projectname">Qwt User's Guide&#160;<span id="projectnumber">5.2.2</span></div>
  </td>
 </tr>
 </tbody>
</table>
</div>
  <div id="navrow1" class="tabs">
    <ul class="tablist">
      <li><a href="index.html"><span>Main&#160;Page</span></a></li>
      <li><a href="pages.html"><span>Related&#160;Pages</span></a></li>
      <li class="current"><a href="annotated.html"><span>Classes</span></a></li>
      <li><a href="files.html"><span>Files</span></a></li>
    </ul>
  </div>
  <div id="navrow2" class="tabs2">
    <ul class="tablist">
      <li><a href="annotated.html"><span>Class&#160;List</span></a></li>
      <li><a href="classes.html"><span>Class&#160;Index</span></a></li>
      <li><a href="inherits.html"><span>Class&#160;Hierarchy</span></a></li>
      <li><a href="functions.html"><span>Class&#160;Members</span></a></li>
    </ul>
  </div>
</div>
<div class="header">
  <div class="summary">
<a href="#pub-types">Public Types</a> &#124;
<a href="#pub-methods">Public Member Functions</a>  </div>
  <div class="headertitle">
<h1>QwtRasterData Class Reference</h1>  </div>
</div>
<div class="contents">
<!-- doxytag: class="QwtRasterData" -->
<p><a class="el" href="class_qwt_raster_data.html" title="QwtRasterData defines an interface to any type of raster data.">QwtRasterData</a> defines an interface to any type of raster data.  
<a href="#_details">More...</a></p>

<p><code>#include &lt;<a class="el" href="qwt__raster__data_8h_source.html">qwt_raster_data.h</a>&gt;</code></p>
<div class="dynheader">
Inheritance diagram for QwtRasterData:</div>
<div class="dyncontent">
<div class="center"><img src="class_qwt_raster_data__inherit__graph.png" border="0" usemap="#_qwt_raster_data_inherit__map" alt="Inheritance graph"/></div>
<map name="_qwt_raster_data_inherit__map" id="_qwt_raster_data_inherit__map">
</map>
<center><span class="legend">[<a href="graph_legend.html">legend</a>]</span></center></div>

<p><a href="class_qwt_raster_data-members.html">List of all members.</a></p>
<table class="memberdecls">
<tr><td colspan="2"><h2><a name="pub-types"></a>
Public Types</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">enum &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_raster_data.html#a8be376c4015dcb4adc207316bccf1140">ConrecAttribute</a> { <br/>
&#160;&#160;<b>IgnoreAllVerticesOnLevel</b> =  1, 
<br/>
&#160;&#160;<b>IgnoreOutOfRange</b> =  2
<br/>
 }</td></tr>
<tr><td class="memItemLeft" align="right" valign="top"><a class="anchor" id="adc6679160a229992f0870a2b784985f3"></a><!-- doxytag: member="QwtRasterData::ContourLines" ref="adc6679160a229992f0870a2b784985f3" args="" -->
typedef QMap&lt; double, QPolygonF &gt;&#160;</td><td class="memItemRight" valign="bottom"><b>ContourLines</b></td></tr>
<tr><td colspan="2"><h2><a name="pub-methods"></a>
Public Member Functions</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">QwtDoubleRect&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_raster_data.html#a2e730c7b31507bb66379f64af3468a25">boundingRect</a> () const </td></tr>
<tr><td class="memItemLeft" align="right" valign="top">virtual ContourLines&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_raster_data.html#a5e62b72075c01a6be21a7d93b8c934d6">contourLines</a> (const QwtDoubleRect &amp;rect, const QSize &amp;raster, const QList&lt; double &gt; &amp;levels, int flags) const </td></tr>
<tr><td class="memItemLeft" align="right" valign="top">virtual <a class="el" href="class_qwt_raster_data.html">QwtRasterData</a> *&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_raster_data.html#a6abfdbd4707ca4095ed6b51584a5c504">copy</a> () const =0</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">virtual void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_raster_data.html#a369a5f525814bf569e01f88fbd8ddb5b">discardRaster</a> ()</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">virtual void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_raster_data.html#a8405182366702abc965a2f938ccf1f14">initRaster</a> (const QwtDoubleRect &amp;, const QSize &amp;raster)</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_raster_data.html#a0fc20e05a794c0dc85f6ae5719566588">QwtRasterData</a> ()</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_raster_data.html#a6bc4af46167b65d2b6eb69d03b87715a">QwtRasterData</a> (const QwtDoubleRect &amp;)</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">virtual <a class="el" href="class_qwt_double_interval.html">QwtDoubleInterval</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_raster_data.html#a6c282a2457d2307d26afe9b84cc0b775">range</a> () const =0</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">virtual QSize&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_raster_data.html#a81e17cbcf24c941526088e6458ba347f">rasterHint</a> (const QwtDoubleRect &amp;) const </td></tr>
<tr><td class="memItemLeft" align="right" valign="top">virtual void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_raster_data.html#a88ec1da25b0beaa9530dd039791399fb">setBoundingRect</a> (const QwtDoubleRect &amp;)</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">virtual double&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_raster_data.html#a6396fc013fcec893b1e8cea4cf03691e">value</a> (double x, double y) const =0</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">virtual&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="class_qwt_raster_data.html#a95b24c7cad42c5f7947e64e990def3e8">~QwtRasterData</a> ()</td></tr>
</table>
<hr/><a name="_details"></a><h2>Detailed Description</h2>
<div class="textblock"><p><a class="el" href="class_qwt_raster_data.html" title="QwtRasterData defines an interface to any type of raster data.">QwtRasterData</a> defines an interface to any type of raster data. </p>
<p><a class="el" href="class_qwt_raster_data.html" title="QwtRasterData defines an interface to any type of raster data.">QwtRasterData</a> is an abstract interface, that is used by <a class="el" href="class_qwt_plot_raster_item.html" title="A class, which displays raster data.">QwtPlotRasterItem</a> to find the values at the pixels of its raster.</p>
<p>Often a raster item is used to display values from a matrix. Then the derived raster data class needs to implement some sort of resampling, that maps the raster of the matrix into the requested raster of the raster item ( depending on resolution and scales of the canvas ). </p>
</div><hr/><h2>Member Enumeration Documentation</h2>
<a class="anchor" id="a8be376c4015dcb4adc207316bccf1140"></a><!-- doxytag: member="QwtRasterData::ConrecAttribute" ref="a8be376c4015dcb4adc207316bccf1140" args="" -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">enum <a class="el" href="class_qwt_raster_data.html#a8be376c4015dcb4adc207316bccf1140">QwtRasterData::ConrecAttribute</a></td>
        </tr>
      </table>
</div>
<div class="memdoc">

<p>Attribute to modify the contour algorithm. </p>

</div>
</div>
<hr/><h2>Constructor &amp; Destructor Documentation</h2>
<a class="anchor" id="a0fc20e05a794c0dc85f6ae5719566588"></a><!-- doxytag: member="QwtRasterData::QwtRasterData" ref="a0fc20e05a794c0dc85f6ae5719566588" args="()" -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">QwtRasterData::QwtRasterData </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td></td>
        </tr>
      </table>
</div>
<div class="memdoc">

<p>Constructor. </p>

</div>
</div>
<a class="anchor" id="a6bc4af46167b65d2b6eb69d03b87715a"></a><!-- doxytag: member="QwtRasterData::QwtRasterData" ref="a6bc4af46167b65d2b6eb69d03b87715a" args="(const QwtDoubleRect &amp;)" -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">QwtRasterData::QwtRasterData </td>
          <td>(</td>
          <td class="paramtype">const QwtDoubleRect &amp;&#160;</td>
          <td class="paramname"><em>boundingRect</em></td><td>)</td>
          <td></td>
        </tr>
      </table>
</div>
<div class="memdoc">
<p>Constructor</p>
<dl><dt><b>Parameters:</b></dt><dd>
  <table class="params">
    <tr><td class="paramname">boundingRect</td><td>Bounding rectangle </td></tr>
  </table>
  </dd>
</dl>
<dl class="see"><dt><b>See also:</b></dt><dd><a class="el" href="class_qwt_raster_data.html#a88ec1da25b0beaa9530dd039791399fb">setBoundingRect()</a> </dd></dl>

</div>
</div>
<a class="anchor" id="a95b24c7cad42c5f7947e64e990def3e8"></a><!-- doxytag: member="QwtRasterData::~QwtRasterData" ref="a95b24c7cad42c5f7947e64e990def3e8" args="()" -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">QwtRasterData::~QwtRasterData </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td><code> [virtual]</code></td>
        </tr>
      </table>
</div>
<div class="memdoc">

<p>Destructor. </p>

</div>
</div>
<hr/><h2>Member Function Documentation</h2>
<a class="anchor" id="a2e730c7b31507bb66379f64af3468a25"></a><!-- doxytag: member="QwtRasterData::boundingRect" ref="a2e730c7b31507bb66379f64af3468a25" args="() const " -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">QwtDoubleRect QwtRasterData::boundingRect </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td> const</td>
        </tr>
      </table>
</div>
<div class="memdoc">
<dl class="return"><dt><b>Returns:</b></dt><dd>Bounding rectangle </dd></dl>
<dl class="see"><dt><b>See also:</b></dt><dd><a class="el" href="class_qwt_raster_data.html#a2e730c7b31507bb66379f64af3468a25">boundingRect()</a> </dd></dl>

</div>
</div>
<a class="anchor" id="a5e62b72075c01a6be21a7d93b8c934d6"></a><!-- doxytag: member="QwtRasterData::contourLines" ref="a5e62b72075c01a6be21a7d93b8c934d6" args="(const QwtDoubleRect &amp;rect, const QSize &amp;raster, const QList&lt; double &gt; &amp;levels, int flags) const " -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">QwtRasterData::ContourLines QwtRasterData::contourLines </td>
          <td>(</td>
          <td class="paramtype">const QwtDoubleRect &amp;&#160;</td>
          <td class="paramname"><em>rect</em>, </td>
        </tr>
        <tr>
          <td class="paramkey"></td>
          <td></td>
          <td class="paramtype">const QSize &amp;&#160;</td>
          <td class="paramname"><em>raster</em>, </td>
        </tr>
        <tr>
          <td class="paramkey"></td>
          <td></td>
          <td class="paramtype">const QList&lt; double &gt; &amp;&#160;</td>
          <td class="paramname"><em>levels</em>, </td>
        </tr>
        <tr>
          <td class="paramkey"></td>
          <td></td>
          <td class="paramtype">int&#160;</td>
          <td class="paramname"><em>flags</em>&#160;</td>
        </tr>
        <tr>
          <td></td>
          <td>)</td>
          <td></td><td> const<code> [virtual]</code></td>
        </tr>
      </table>
</div>
<div class="memdoc">
<p>Calculate contour lines</p>
<p>An adaption of CONREC, a simple contouring algorithm. <a href="http://local.wasp.uwa.edu.au/~pbourke/papers/conrec/">http://local.wasp.uwa.edu.au/~pbourke/papers/conrec/</a> </p>

</div>
</div>
<a class="anchor" id="a6abfdbd4707ca4095ed6b51584a5c504"></a><!-- doxytag: member="QwtRasterData::copy" ref="a6abfdbd4707ca4095ed6b51584a5c504" args="() const =0" -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">virtual <a class="el" href="class_qwt_raster_data.html">QwtRasterData</a>* QwtRasterData::copy </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td> const<code> [pure virtual]</code></td>
        </tr>
      </table>
</div>
<div class="memdoc">

<p>Clone the data. </p>

</div>
</div>
<a class="anchor" id="a369a5f525814bf569e01f88fbd8ddb5b"></a><!-- doxytag: member="QwtRasterData::discardRaster" ref="a369a5f525814bf569e01f88fbd8ddb5b" args="()" -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">void QwtRasterData::discardRaster </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td><code> [virtual]</code></td>
        </tr>
      </table>
</div>
<div class="memdoc">

<p>Discard a raster. </p>
<p>After the composition of an image <a class="el" href="class_qwt_plot_spectrogram.html" title="A plot item, which displays a spectrogram.">QwtPlotSpectrogram</a> calls <a class="el" href="class_qwt_raster_data.html#a369a5f525814bf569e01f88fbd8ddb5b" title="Discard a raster.">discardRaster()</a>.</p>
<p>The default implementation does nothing, but if data has been loaded in <a class="el" href="class_qwt_raster_data.html#a8405182366702abc965a2f938ccf1f14" title="Initialize a raster.">initRaster()</a>, it could deleted now.</p>
<dl class="see"><dt><b>See also:</b></dt><dd><a class="el" href="class_qwt_raster_data.html#a8405182366702abc965a2f938ccf1f14" title="Initialize a raster.">initRaster()</a>, <a class="el" href="class_qwt_raster_data.html#a6396fc013fcec893b1e8cea4cf03691e">value()</a> </dd></dl>

</div>
</div>
<a class="anchor" id="a8405182366702abc965a2f938ccf1f14"></a><!-- doxytag: member="QwtRasterData::initRaster" ref="a8405182366702abc965a2f938ccf1f14" args="(const QwtDoubleRect &amp;, const QSize &amp;raster)" -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">void QwtRasterData::initRaster </td>
          <td>(</td>
          <td class="paramtype">const QwtDoubleRect &amp;&#160;</td>
          <td class="paramname">, </td>
        </tr>
        <tr>
          <td class="paramkey"></td>
          <td></td>
          <td class="paramtype">const QSize &amp;&#160;</td>
          <td class="paramname"><em>raster</em>&#160;</td>
        </tr>
        <tr>
          <td></td>
          <td>)</td>
          <td></td><td><code> [virtual]</code></td>
        </tr>
      </table>
</div>
<div class="memdoc">

<p>Initialize a raster. </p>
<p>Before the composition of an image <a class="el" href="class_qwt_plot_spectrogram.html" title="A plot item, which displays a spectrogram.">QwtPlotSpectrogram</a> calls initRaster, announcing the area and its resolution that will be requested.</p>
<p>The default implementation does nothing, but for data sets that are stored in files, it might be good idea to reimplement initRaster, where the data is resampled and loaded into memory.</p>
<dl><dt><b>Parameters:</b></dt><dd>
  <table class="params">
    <tr><td class="paramname">rect</td><td>Area of the raster </td></tr>
    <tr><td class="paramname">raster</td><td>Number of horizontal and vertical pixels</td></tr>
  </table>
  </dd>
</dl>
<dl class="see"><dt><b>See also:</b></dt><dd><a class="el" href="class_qwt_raster_data.html#a8405182366702abc965a2f938ccf1f14" title="Initialize a raster.">initRaster()</a>, <a class="el" href="class_qwt_raster_data.html#a6396fc013fcec893b1e8cea4cf03691e">value()</a> </dd></dl>

</div>
</div>
<a class="anchor" id="a6c282a2457d2307d26afe9b84cc0b775"></a><!-- doxytag: member="QwtRasterData::range" ref="a6c282a2457d2307d26afe9b84cc0b775" args="() const =0" -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">virtual <a class="el" href="class_qwt_double_interval.html">QwtDoubleInterval</a> QwtRasterData::range </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td> const<code> [pure virtual]</code></td>
        </tr>
      </table>
</div>
<div class="memdoc">
<dl class="return"><dt><b>Returns:</b></dt><dd>the range of the values </dd></dl>

</div>
</div>
<a class="anchor" id="a81e17cbcf24c941526088e6458ba347f"></a><!-- doxytag: member="QwtRasterData::rasterHint" ref="a81e17cbcf24c941526088e6458ba347f" args="(const QwtDoubleRect &amp;) const " -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">QSize QwtRasterData::rasterHint </td>
          <td>(</td>
          <td class="paramtype">const QwtDoubleRect &amp;&#160;</td>
          <td class="paramname"></td><td>)</td>
          <td> const<code> [virtual]</code></td>
        </tr>
      </table>
</div>
<div class="memdoc">

<p>Find the raster of the data for an area. </p>
<p>The resolution is the number of horizontal and vertical pixels that the data can return for an area. An invalid resolution indicates that the data can return values for any detail level.</p>
<p>The resolution will limit the size of the image that is rendered from the data. F.e. this might be important when printing a spectrogram to a A0 printer with 600 dpi.</p>
<p>The default implementation returns an invalid resolution (size)</p>
<dl><dt><b>Parameters:</b></dt><dd>
  <table class="params">
    <tr><td class="paramname">rect</td><td>In most implementations the resolution of the data doesn't depend on the requested rectangle.</td></tr>
  </table>
  </dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>Resolution, as number of horizontal and vertical pixels </dd></dl>

</div>
</div>
<a class="anchor" id="a88ec1da25b0beaa9530dd039791399fb"></a><!-- doxytag: member="QwtRasterData::setBoundingRect" ref="a88ec1da25b0beaa9530dd039791399fb" args="(const QwtDoubleRect &amp;)" -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">void QwtRasterData::setBoundingRect </td>
          <td>(</td>
          <td class="paramtype">const QwtDoubleRect &amp;&#160;</td>
          <td class="paramname"><em>boundingRect</em></td><td>)</td>
          <td><code> [virtual]</code></td>
        </tr>
      </table>
</div>
<div class="memdoc">
<p>Set the bounding rect ( == area, un plot coordinates )</p>
<dl><dt><b>Parameters:</b></dt><dd>
  <table class="params">
    <tr><td class="paramname">boundingRect</td><td>Bounding rectangle </td></tr>
  </table>
  </dd>
</dl>
<dl class="see"><dt><b>See also:</b></dt><dd><a class="el" href="class_qwt_raster_data.html#a2e730c7b31507bb66379f64af3468a25">boundingRect()</a> </dd></dl>

</div>
</div>
<a class="anchor" id="a6396fc013fcec893b1e8cea4cf03691e"></a><!-- doxytag: member="QwtRasterData::value" ref="a6396fc013fcec893b1e8cea4cf03691e" args="(double x, double y) const =0" -->
<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname">virtual double QwtRasterData::value </td>
          <td>(</td>
          <td class="paramtype">double&#160;</td>
          <td class="paramname"><em>x</em>, </td>
        </tr>
        <tr>
          <td class="paramkey"></td>
          <td></td>
          <td class="paramtype">double&#160;</td>
          <td class="paramname"><em>y</em>&#160;</td>
        </tr>
        <tr>
          <td></td>
          <td>)</td>
          <td></td><td> const<code> [pure virtual]</code></td>
        </tr>
      </table>
</div>
<div class="memdoc">
<dl class="return"><dt><b>Returns:</b></dt><dd>the value at a raster position </dd></dl>
<dl><dt><b>Parameters:</b></dt><dd>
  <table class="params">
    <tr><td class="paramname">x</td><td>X value in plot coordinates </td></tr>
    <tr><td class="paramname">y</td><td>Y value in plot coordinates </td></tr>
  </table>
  </dd>
</dl>

</div>
</div>
</div>
<hr class="footer"/><address class="footer"><small>Generated by&#160;
<a href="http://www.doxygen.org/index.html">
<img class="footer" src="doxygen.png" alt="doxygen"/></a> 1.7.3 </small></address>
</body>
</html>