source: ntrip/trunk/BNC/qwt/qwt_scale_map.cpp@ 7905

Last change on this file since 7905 was 4271, checked in by mervart, 12 years ago
File size: 8.5 KB
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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#include "qwt_scale_map.h"
11#include <qrect.h>
12#include <qalgorithms.h>
13#include <qmath.h>
14#include <qdebug.h>
15
16#if QT_VERSION < 0x040601
17#define qExp(x) ::exp(x)
18#endif
19
20//! Smallest allowed value for logarithmic scales: 1.0e-150
21QT_STATIC_CONST_IMPL double QwtScaleMap::LogMin = 1.0e-150;
22
23//! Largest allowed value for logarithmic scales: 1.0e150
24QT_STATIC_CONST_IMPL double QwtScaleMap::LogMax = 1.0e150;
25
26//! Constructor for a linear transformation
27QwtScaleTransformation::QwtScaleTransformation( Type type ):
28 d_type( type )
29{
30}
31
32//! Destructor
33QwtScaleTransformation::~QwtScaleTransformation()
34{
35}
36
37//! Create a clone of the transformation
38QwtScaleTransformation *QwtScaleTransformation::copy() const
39{
40 return new QwtScaleTransformation( d_type );
41}
42
43/*!
44 \brief Transform a value from the coordinate system of a scale
45 into the coordinate system of the paint device
46
47 \param s Value related to the coordinate system of the scale
48 \param s1 First border of the coordinate system of the scale
49 \param s2 Second border of the coordinate system of the scale
50 \param p1 First border of the coordinate system of the paint device
51 \param p2 Second border of the coordinate system of the paint device
52 \return
53 <dl>
54 <dt>linear mapping:<dd>p1 + (p2 - p1) / (s2 - s1) * (s - s1);</dd>
55 </dl>
56 <dl>
57 <dt>log10 mapping: <dd>p1 + (p2 - p1) / log(s2 / s1) * log(s / s1);</dd>
58 </dl>
59*/
60
61double QwtScaleTransformation::xForm(
62 double s, double s1, double s2, double p1, double p2 ) const
63{
64 if ( d_type == Log10 )
65 return p1 + ( p2 - p1 ) / log( s2 / s1 ) * log( s / s1 );
66 else
67 return p1 + ( p2 - p1 ) / ( s2 - s1 ) * ( s - s1 );
68}
69
70/*!
71 \brief Transform a value from the coordinate system of the paint device
72 into the coordinate system of a scale.
73
74 \param p Value related to the coordinate system of the paint device
75 \param p1 First border of the coordinate system of the paint device
76 \param p2 Second border of the coordinate system of the paint device
77 \param s1 First border of the coordinate system of the scale
78 \param s2 Second border of the coordinate system of the scale
79 \return
80 <dl>
81 <dt>linear mapping:<dd>s1 + ( s2 - s1 ) / ( p2 - p1 ) * ( p - p1 );</dd>
82 </dl>
83 <dl>
84 <dt>log10 mapping:<dd>exp((p - p1) / (p2 - p1) * log(s2 / s1)) * s1;</dd>
85 </dl>
86*/
87
88double QwtScaleTransformation::invXForm( double p, double p1, double p2,
89 double s1, double s2 ) const
90{
91 if ( d_type == Log10 )
92 return qExp( ( p - p1 ) / ( p2 - p1 ) * log( s2 / s1 ) ) * s1;
93 else
94 return s1 + ( s2 - s1 ) / ( p2 - p1 ) * ( p - p1 );
95}
96
97/*!
98 \brief Constructor
99
100 The scale and paint device intervals are both set to [0,1].
101*/
102QwtScaleMap::QwtScaleMap():
103 d_s1( 0.0 ),
104 d_s2( 1.0 ),
105 d_p1( 0.0 ),
106 d_p2( 1.0 ),
107 d_cnv( 1.0 )
108{
109 d_transformation = new QwtScaleTransformation(
110 QwtScaleTransformation::Linear );
111}
112
113//! Copy constructor
114QwtScaleMap::QwtScaleMap( const QwtScaleMap& other ):
115 d_s1( other.d_s1 ),
116 d_s2( other.d_s2 ),
117 d_p1( other.d_p1 ),
118 d_p2( other.d_p2 ),
119 d_cnv( other.d_cnv )
120{
121 d_transformation = other.d_transformation->copy();
122}
123
124/*!
125 Destructor
126*/
127QwtScaleMap::~QwtScaleMap()
128{
129 delete d_transformation;
130}
131
132//! Assignment operator
133QwtScaleMap &QwtScaleMap::operator=( const QwtScaleMap & other )
134{
135 d_s1 = other.d_s1;
136 d_s2 = other.d_s2;
137 d_p1 = other.d_p1;
138 d_p2 = other.d_p2;
139 d_cnv = other.d_cnv;
140
141 delete d_transformation;
142 d_transformation = other.d_transformation->copy();
143
144 return *this;
145}
146
147/*!
148 Initialize the map with a transformation
149*/
150void QwtScaleMap::setTransformation(
151 QwtScaleTransformation *transformation )
152{
153 if ( transformation == NULL )
154 return;
155
156 if ( transformation != d_transformation )
157 {
158 delete d_transformation;
159 d_transformation = transformation;
160 }
161
162 setScaleInterval( d_s1, d_s2 );
163}
164
165//! Get the transformation
166const QwtScaleTransformation *QwtScaleMap::transformation() const
167{
168 return d_transformation;
169}
170
171/*!
172 \brief Specify the borders of the scale interval
173 \param s1 first border
174 \param s2 second border
175 \warning logarithmic scales might be aligned to [LogMin, LogMax]
176*/
177void QwtScaleMap::setScaleInterval( double s1, double s2 )
178{
179 if ( d_transformation->type() == QwtScaleTransformation::Log10 )
180 {
181 if ( s1 < LogMin )
182 s1 = LogMin;
183 else if ( s1 > LogMax )
184 s1 = LogMax;
185
186 if ( s2 < LogMin )
187 s2 = LogMin;
188 else if ( s2 > LogMax )
189 s2 = LogMax;
190 }
191
192 d_s1 = s1;
193 d_s2 = s2;
194
195 if ( d_transformation->type() != QwtScaleTransformation::Other )
196 newFactor();
197}
198
199/*!
200 \brief Specify the borders of the paint device interval
201 \param p1 first border
202 \param p2 second border
203*/
204void QwtScaleMap::setPaintInterval( double p1, double p2 )
205{
206 d_p1 = p1;
207 d_p2 = p2;
208
209 if ( d_transformation->type() != QwtScaleTransformation::Other )
210 newFactor();
211}
212
213/*!
214 \brief Re-calculate the conversion factor.
215*/
216void QwtScaleMap::newFactor()
217{
218 d_cnv = 0.0;
219
220 switch ( d_transformation->type() )
221 {
222 case QwtScaleTransformation::Linear:
223 {
224 if ( d_s2 != d_s1 )
225 d_cnv = ( d_p2 - d_p1 ) / ( d_s2 - d_s1 );
226 break;
227 }
228 case QwtScaleTransformation::Log10:
229 {
230 if ( d_s1 != 0 )
231 d_cnv = ( d_p2 - d_p1 ) / log( d_s2 / d_s1 );
232 break;
233 }
234 default:;
235 }
236}
237
238/*!
239 Transform a rectangle from scale to paint coordinates
240
241 \param xMap X map
242 \param yMap Y map
243 \param rect Rectangle in scale coordinates
244 \return Rectangle in paint coordinates
245
246 \sa invTransform()
247*/
248QRectF QwtScaleMap::transform( const QwtScaleMap &xMap,
249 const QwtScaleMap &yMap, const QRectF &rect )
250{
251 double x1 = xMap.transform( rect.left() );
252 double x2 = xMap.transform( rect.right() );
253 double y1 = yMap.transform( rect.top() );
254 double y2 = yMap.transform( rect.bottom() );
255
256 if ( x2 < x1 )
257 qSwap( x1, x2 );
258 if ( y2 < y1 )
259 qSwap( y1, y2 );
260
261 if ( qwtFuzzyCompare( x1, 0.0, x2 - x1 ) == 0 )
262 x1 = 0.0;
263 if ( qwtFuzzyCompare( x2, 0.0, x2 - x1 ) == 0 )
264 x2 = 0.0;
265 if ( qwtFuzzyCompare( y1, 0.0, y2 - y1 ) == 0 )
266 y1 = 0.0;
267 if ( qwtFuzzyCompare( y2, 0.0, y2 - y1 ) == 0 )
268 y2 = 0.0;
269
270 return QRectF( x1, y1, x2 - x1 + 1, y2 - y1 + 1 );
271}
272
273/*!
274 Transform a rectangle from paint to scale coordinates
275
276 \param xMap X map
277 \param yMap Y map
278 \param pos Position in paint coordinates
279 \return Position in scale coordinates
280 \sa transform()
281*/
282QPointF QwtScaleMap::invTransform( const QwtScaleMap &xMap,
283 const QwtScaleMap &yMap, const QPointF &pos )
284{
285 return QPointF(
286 xMap.invTransform( pos.x() ),
287 yMap.invTransform( pos.y() )
288 );
289}
290
291/*!
292 Transform a point from scale to paint coordinates
293
294 \param xMap X map
295 \param yMap Y map
296 \param pos Position in scale coordinates
297 \return Position in paint coordinates
298
299 \sa invTransform()
300*/
301QPointF QwtScaleMap::transform( const QwtScaleMap &xMap,
302 const QwtScaleMap &yMap, const QPointF &pos )
303{
304 return QPointF(
305 xMap.transform( pos.x() ),
306 yMap.transform( pos.y() )
307 );
308}
309
310/*!
311 Transform a rectangle from paint to scale coordinates
312
313 \param xMap X map
314 \param yMap Y map
315 \param rect Rectangle in paint coordinates
316 \return Rectangle in scale coordinates
317 \sa transform()
318*/
319QRectF QwtScaleMap::invTransform( const QwtScaleMap &xMap,
320 const QwtScaleMap &yMap, const QRectF &rect )
321{
322 const double x1 = xMap.invTransform( rect.left() );
323 const double x2 = xMap.invTransform( rect.right() - 1 );
324 const double y1 = yMap.invTransform( rect.top() );
325 const double y2 = yMap.invTransform( rect.bottom() - 1 );
326
327 const QRectF r( x1, y1, x2 - x1, y2 - y1 );
328 return r.normalized();
329}
330
331#ifndef QT_NO_DEBUG_STREAM
332
333QDebug operator<<( QDebug debug, const QwtScaleMap &map )
334{
335 debug.nospace() << "QwtScaleMap("
336 << static_cast<int>( map.transformation()->type() )
337 << ", s:" << map.s1() << "->" << map.s2()
338 << ", p:" << map.p1() << "->" << map.p2()
339 << ")";
340
341 return debug.space();
342}
343
344#endif
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