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qgis.h
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1 /***************************************************************************
2  qgis.h - QGIS namespace
3  -------------------
4  begin : Sat Jun 30 2002
5  copyright : (C) 2002 by Gary E.Sherman
6  email : sherman at mrcc.com
7  ***************************************************************************/
8 
9 /***************************************************************************
10  * *
11  * This program is free software; you can redistribute it and/or modify *
12  * it under the terms of the GNU General Public License as published by *
13  * the Free Software Foundation; either version 2 of the License, or *
14  * (at your option) any later version. *
15  * *
16  ***************************************************************************/
17 
18 #ifndef QGIS_H
19 #define QGIS_H
20 
21 #include <QEvent>
22 #include <QString>
23 #include <QRegExp>
24 #include <QMetaType>
25 #include <QVariant>
26 #include <stdlib.h>
27 #include <cfloat>
28 #include <cmath>
29 #include <qnumeric.h>
30 
34 class CORE_EXPORT QGis
35 {
36  public:
37  // Version constants
38  //
39  // Version string
40  static const char* QGIS_VERSION;
41  // Version number used for comparing versions using the "Check QGIS Version" function
42  static const int QGIS_VERSION_INT;
43  // Release name
44  static const char* QGIS_RELEASE_NAME;
45  // The development version
46  static const char* QGIS_DEV_VERSION;
47 
48  // Enumerations
49  //
50 
52  // Feature types
53  enum WkbType
54  {
55  WKBUnknown = 0,
56  WKBPoint = 1,
62  WKBNoGeometry = 100, //attributes only
63  WKBPoint25D = 0x80000001,
69  };
70 
71  static WkbType singleType( WkbType type )
72  {
73  switch ( type )
74  {
75  case WKBMultiPoint: return WKBPoint;
76  case WKBMultiLineString: return WKBLineString;
77  case WKBMultiPolygon: return WKBPolygon;
78  case WKBMultiPoint25D: return WKBPoint25D;
79  case WKBMultiLineString25D: return WKBLineString25D;
80  case WKBMultiPolygon25D: return WKBPolygon25D;
81  default: return type;
82  }
83  }
84 
85  static WkbType multiType( WkbType type )
86  {
87  switch ( type )
88  {
89  case WKBPoint: return WKBMultiPoint;
90  case WKBLineString: return WKBMultiLineString;
91  case WKBPolygon: return WKBMultiPolygon;
92  case WKBPoint25D: return WKBMultiPoint25D;
93  case WKBLineString25D: return WKBMultiLineString25D;
94  case WKBPolygon25D: return WKBMultiPolygon25D;
95  default: return type;
96  }
97  }
98 
99  static WkbType flatType( WkbType type )
100  {
101  switch ( type )
102  {
103  case WKBPoint25D: return WKBPoint;
104  case WKBLineString25D: return WKBLineString;
105  case WKBPolygon25D: return WKBPolygon;
106  case WKBMultiPoint25D: return WKBMultiPoint;
107  case WKBMultiLineString25D: return WKBMultiLineString;
108  case WKBMultiPolygon25D: return WKBMultiPolygon;
109  default: return type;
110  }
111  }
112 
113  static bool isSingleType( WkbType type )
114  {
115  switch ( flatType( type ) )
116  {
117  case WKBPoint:
118  case WKBLineString:
119  case WKBPolygon:
120  return true;
121  default:
122  return false;
123  }
124  }
125 
126  static bool isMultiType( WkbType type )
127  {
128  switch ( flatType( type ) )
129  {
130  case WKBMultiPoint:
131  case WKBMultiLineString:
132  case WKBMultiPolygon:
133  return true;
134  default:
135  return false;
136  }
137  }
138 
139  static int wkbDimensions( WkbType type )
140  {
141  switch ( type )
142  {
143  case WKBUnknown: return 0;
144  case WKBNoGeometry: return 0;
145  case WKBPoint25D: return 3;
146  case WKBLineString25D: return 3;
147  case WKBPolygon25D: return 3;
148  case WKBMultiPoint25D: return 3;
149  case WKBMultiLineString25D: return 3;
150  case WKBMultiPolygon25D: return 3;
151  default: return 2;
152  }
153  }
154 
156  {
161  NoGeometry
162  };
163 
165  static const char *vectorGeometryType( GeometryType type )
166  {
167  switch ( type )
168  {
169  case Point: return "Point";
170  case Line: return "Line";
171  case Polygon: return "Polygon";
172  case UnknownGeometry: return "Unknown geometry";
173  case NoGeometry: return "No geometry";
174  default: return "Invalid type";
175  }
176  }
177 
179  static const char *featureType( WkbType type )
180  {
181  switch ( type )
182  {
183  case WKBUnknown: return "WKBUnknown";
184  case WKBPoint: return "WKBPoint";
185  case WKBLineString: return "WKBLineString";
186  case WKBPolygon: return "WKBPolygon";
187  case WKBMultiPoint: return "WKBMultiPoint";
188  case WKBMultiLineString: return "WKBMultiLineString";
189  case WKBMultiPolygon: return "WKBMultiPolygon";
190  case WKBNoGeometry: return "WKBNoGeometry";
191  case WKBPoint25D: return "WKBPoint25D";
192  case WKBLineString25D: return "WKBLineString25D";
193  case WKBPolygon25D: return "WKBPolygon25D";
194  case WKBMultiPoint25D: return "WKBMultiPoint25D";
195  case WKBMultiLineString25D: return "WKBMultiLineString25D";
196  case WKBMultiPolygon25D: return "WKBMultiPolygon25D";
197  default: return "invalid wkbtype";
198  }
199  }
200 
204  enum DataType
205  { UnknownDataType = 0, Byte = 1, UInt16 = 2, Int16 = 3, UInt32 = 4, Int32 = 5, Float32 = 6, Float64 = 7, CInt16 = 8, CInt32 = 9, CFloat32 = 10, CFloat64 = 11, ARGB32 = 12, ARGB32_Premultiplied = 13
222  };
223 
224 
229  enum UnitType
230  {
231  Meters = 0,
232  Feet = 1,
233  Degrees = 2, //for 1.0 api backwards compatibility
234  UnknownUnit = 3,
235 
236  // for [1.4;1.8] api compatibility
237  DecimalDegrees = 2, // was 2
238  DegreesMinutesSeconds = 2, // was 4
239  DegreesDecimalMinutes = 2, // was 5
240  NauticalMiles = 7
241  };
242 
244  static QString toLiteral( QGis::UnitType unit );
246  static UnitType fromLiteral( QString literal, QGis::UnitType defaultType = UnknownUnit );
248  static QString tr( QGis::UnitType unit );
250  static UnitType fromTr( QString literal, QGis::UnitType defaultType = UnknownUnit );
252  static double fromUnitToUnitFactor( QGis::UnitType fromUnit, QGis::UnitType toUnit );
253 
256  {
257  // These first two are useful for threads to alert their parent data providers
258 
260  ProviderExtentCalcEvent = ( QEvent::User + 1 ),
261 
263  ProviderCountCalcEvent
264  };
265 
268  static const double DEFAULT_IDENTIFY_RADIUS;
269 
272  static const double DEFAULT_SEARCH_RADIUS_MM;
273 
275  static const float DEFAULT_MAPTOPIXEL_THRESHOLD;
276 
280  static const QColor DEFAULT_HIGHLIGHT_COLOR;
281 
285 
289 
290  private:
291  // String representation of unit types (set in qgis.cpp)
292  static const char *qgisUnitTypes[];
293 
294 };
295 
296 // hack to workaround warnings when casting void pointers
297 // retrieved from QLibrary::resolve to function pointers.
298 // It's assumed that this works on all systems supporting
299 // QLibrary
300 #if QT_VERSION >= 0x050000
301 #define cast_to_fptr(f) f
302 #else
303 inline void ( *cast_to_fptr( void *p ) )()
304 {
305  union
306  {
307  void *p;
308  void ( *f )();
309  } u;
310 
311  u.p = p;
312  return u.f;
313 }
314 #endif
315 
316 //
317 // return a string representation of a double
318 //
319 inline QString qgsDoubleToString( const double &a, const int &precision = 17 )
320 {
321  return QString::number( a, 'f', precision ).remove( QRegExp( "\\.?0+$" ) );
322 }
323 
324 //
325 // compare two doubles (but allow some difference)
326 //
327 inline bool qgsDoubleNear( double a, double b, double epsilon = 4 * DBL_EPSILON )
328 {
329  const double diff = a - b;
330  return diff > -epsilon && diff <= epsilon;
331 }
332 
333 //
334 // compare two doubles using specified number of significant digits
335 //
336 inline bool qgsDoubleNearSig( double a, double b, int significantDigits = 10 )
337 {
338  // The most simple would be to print numbers as %.xe and compare as strings
339  // but that is probably too costly
340  // Then the fastest would be to set some bits directly, but little/big endian
341  // has to be considered (maybe TODO)
342  // Is there a better way?
343  int aexp, bexp;
344  double ar = frexp( a, &aexp );
345  double br = frexp( b, &bexp );
346 
347  return aexp == bexp &&
348  qRound( ar * pow( 10.0, significantDigits ) ) == qRound( br * pow( 10.0, significantDigits ) );
349 }
350 
351 bool qgsVariantLessThan( const QVariant& lhs, const QVariant& rhs );
352 
353 bool qgsVariantGreaterThan( const QVariant& lhs, const QVariant& rhs );
354 
355 QString qgsVsiPrefix( QString path );
356 
361 void CORE_EXPORT *qgsMalloc( size_t size );
362 
369 void CORE_EXPORT *qgsCalloc( size_t nmemb, size_t size );
370 
374 void CORE_EXPORT qgsFree( void *ptr );
375 
379 extern CORE_EXPORT const QString GEOWKT;
380 extern CORE_EXPORT const QString PROJECT_SCALES;
381 
383 extern CORE_EXPORT const QString GEOPROJ4;
385 const long GEOSRID = 4326;
387 const long GEOCRS_ID = 3452;
389 const long GEO_EPSG_CRS_ID = 4326;
391 extern CORE_EXPORT const QString GEO_EPSG_CRS_AUTHID;
393 const int PROJ_PREFIX_LEN = 6;
395 const int ELLPS_PREFIX_LEN = 7;
397 const int LAT_PREFIX_LEN = 7;
400 const int USER_CRS_START_ID = 100000;
401 
403 extern CORE_EXPORT const QString GEO_NONE;
404 
405 //
406 // Constants for point symbols
407 //
408 
410 const double MINIMUM_POINT_SIZE = 0.1;
412 const double DEFAULT_POINT_SIZE = 2.0;
413 const double DEFAULT_LINE_WIDTH = 0.26;
414 
416 const double DEFAULT_SEGMENT_EPSILON = 1e-8;
417 
418 typedef QMap<QString, QString> QgsStringMap;
419 
426 typedef unsigned long long qgssize;
427 
428 #if (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)) || defined(__clang__)
429 #define Q_NOWARN_DEPRECATED_PUSH \
430  _Pragma("GCC diagnostic push") \
431  _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
432 #define Q_NOWARN_DEPRECATED_POP \
433  _Pragma("GCC diagnostic pop")
434 #elif defined(_MSC_VER)
435 #define Q_NOWARN_DEPRECATED_PUSH \
436  __pragma(warning(push)) \
437  __pragma(warning(disable:4996))
438 #define Q_NOWARN_DEPRECATED_POP \
439  __pragma(warning(pop))
440 #else
441 #define Q_NOWARN_DEPRECATED_PUSH
442 #define Q_NOWARN_DEPRECATED_POP
443 #endif
444 
445 // FIXME: also in qgisinterface.h
446 #ifndef QGISEXTERN
447 #ifdef WIN32
448 # define QGISEXTERN extern "C" __declspec( dllexport )
449 # ifdef _MSC_VER
450 // do not warn about C bindings returing QString
451 # pragma warning(disable:4190)
452 # endif
453 #else
454 # define QGISEXTERN extern "C"
455 #endif
456 #endif
457 #endif