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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 double fromUnitToUnitFactor( QGis::UnitType fromUnit, QGis::UnitType toUnit );
251 
254  {
255  // These first two are useful for threads to alert their parent data providers
256 
258  ProviderExtentCalcEvent = ( QEvent::User + 1 ),
259 
261  ProviderCountCalcEvent
262  };
263 
266  static const double DEFAULT_IDENTIFY_RADIUS;
267 
270  static const double DEFAULT_SEARCH_RADIUS_MM;
271 
273  static const float DEFAULT_MAPTOPIXEL_THRESHOLD;
274 
278  static const QColor DEFAULT_HIGHLIGHT_COLOR;
279 
283 
287 
288  private:
289  // String representation of unit types (set in qgis.cpp)
290  static const char *qgisUnitTypes[];
291 
292 };
293 
294 // hack to workaround warnings when casting void pointers
295 // retrieved from QLibrary::resolve to function pointers.
296 // It's assumed that this works on all systems supporting
297 // QLibrary
298 inline void ( *cast_to_fptr( void *p ) )()
299 {
300  union
301  {
302  void *p;
303  void ( *f )();
304  } u;
305 
306  u.p = p;
307  return u.f;
308 }
309 
310 //
311 // return a string representation of a double
312 //
313 inline QString qgsDoubleToString( const double &a, const int &precision = 17 )
314 {
315  return QString::number( a, 'f', precision ).remove( QRegExp( "\\.?0+$" ) );
316 }
317 
318 //
319 // compare two doubles (but allow some difference)
320 //
321 inline bool qgsDoubleNear( double a, double b, double epsilon = 4 * DBL_EPSILON )
322 {
323  const double diff = a - b;
324  return diff > -epsilon && diff <= epsilon;
325 }
326 
327 //
328 // compare two doubles using specified number of significant digits
329 //
330 inline bool qgsDoubleNearSig( double a, double b, int significantDigits = 10 )
331 {
332  // The most simple would be to print numbers as %.xe and compare as strings
333  // but that is probably too costly
334  // Then the fastest would be to set some bits directly, but little/big endian
335  // has to be considered (maybe TODO)
336  // Is there a better way?
337  int aexp, bexp;
338  double ar = frexp( a, &aexp );
339  double br = frexp( b, &bexp );
340 
341  return aexp == bexp &&
342  qRound( ar * pow( 10.0, significantDigits ) ) == qRound( br * pow( 10.0, significantDigits ) );
343 }
344 
345 bool qgsVariantLessThan( const QVariant& lhs, const QVariant& rhs );
346 
347 bool qgsVariantGreaterThan( const QVariant& lhs, const QVariant& rhs );
348 
349 QString qgsVsiPrefix( QString path );
350 
355 void CORE_EXPORT *qgsMalloc( size_t size );
356 
363 void CORE_EXPORT *qgsCalloc( size_t nmemb, size_t size );
364 
368 void CORE_EXPORT qgsFree( void *ptr );
369 
373 extern CORE_EXPORT const QString GEOWKT;
374 extern CORE_EXPORT const QString PROJECT_SCALES;
375 
377 extern CORE_EXPORT const QString GEOPROJ4;
379 const long GEOSRID = 4326;
381 const long GEOCRS_ID = 3452;
383 const long GEO_EPSG_CRS_ID = 4326;
385 extern CORE_EXPORT const QString GEO_EPSG_CRS_AUTHID;
387 const int PROJ_PREFIX_LEN = 6;
389 const int ELLPS_PREFIX_LEN = 7;
391 const int LAT_PREFIX_LEN = 7;
394 const int USER_CRS_START_ID = 100000;
395 
397 extern CORE_EXPORT const QString GEO_NONE;
398 
399 //
400 // Constants for point symbols
401 //
402 
404 const double MINIMUM_POINT_SIZE = 0.1;
406 const double DEFAULT_POINT_SIZE = 2.0;
407 const double DEFAULT_LINE_WIDTH = 0.26;
408 
410 const double DEFAULT_SEGMENT_EPSILON = 1e-8;
411 
412 typedef QMap<QString, QString> QgsStringMap;
413 
420 typedef unsigned long long qgssize;
421 
422 #if (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)) || defined(__clang__)
423 #define Q_NOWARN_DEPRECATED_PUSH \
424  _Pragma("GCC diagnostic push") \
425  _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
426 #define Q_NOWARN_DEPRECATED_POP \
427  _Pragma("GCC diagnostic pop")
428 #elif defined(_MSC_VER)
429 #define Q_NOWARN_DEPRECATED_PUSH \
430  __pragma(warning(push)) \
431  __pragma(warning(disable:4996))
432 #define Q_NOWARN_DEPRECATED_POP \
433  __pragma(warning(pop))
434 #else
435 #define Q_NOWARN_DEPRECATED_PUSH
436 #define Q_NOWARN_DEPRECATED_POP
437 #endif
438 
439 // FIXME: also in qgisinterface.h
440 #ifndef QGISEXTERN
441 #ifdef WIN32
442 # define QGISEXTERN extern "C" __declspec( dllexport )
443 # ifdef _MSC_VER
444 // do not warn about C bindings returing QString
445 # pragma warning(disable:4190)
446 # endif
447 #else
448 # define QGISEXTERN extern "C"
449 #endif
450 #endif
451 #endif
static WkbType singleType(WkbType type)
Definition: qgis.h:71
static const char * QGIS_VERSION
Definition: qgis.h:40
Definition: qgis.h:57
static double DEFAULT_HIGHLIGHT_BUFFER_MM
Default highlight buffer in mm.
Definition: qgis.h:282
static const QColor DEFAULT_HIGHLIGHT_COLOR
Default highlight color.
Definition: qgis.h:278
Definition: qgis.h:159
Definition: qgis.h:58
Definition: qgis.h:157
UnitType
Map units that qgis supports.
Definition: qgis.h:229
Definition: qgis.h:65
Definition: qgis.h:67
UserEvent
User defined event types.
Definition: qgis.h:253
Definition: qgis.h:59
Definition: qgis.h:60
static const char * vectorGeometryType(GeometryType type)
description strings for geometry types
Definition: qgis.h:165
static const double DEFAULT_IDENTIFY_RADIUS
Old search radius in % of canvas width.
Definition: qgis.h:266
GeometryType
Definition: qgis.h:155
The QGis class provides global constants for use throughout the application.
Definition: qgis.h:34
WkbType
Used for symbology operations.
Definition: qgis.h:53
void CORE_EXPORT * qgsCalloc(size_t nmemb, size_t size)
Allocates memory for an array of nmemb elements of size bytes each and returns a pointer to the alloc...
Definition: qgis.cpp:190
QMap< QString, QString > QgsStringMap
Definition: qgis.h:412
bool qgsDoubleNear(double a, double b, double epsilon=4 *DBL_EPSILON)
Definition: qgis.h:321
Definition: qgis.h:160
bool qgsVariantLessThan(const QVariant &lhs, const QVariant &rhs)
Definition: qgis.cpp:210
static WkbType flatType(WkbType type)
Definition: qgis.h:99
static bool isSingleType(WkbType type)
Definition: qgis.h:113
CORE_EXPORT const QString GEO_NONE
Constant that holds the string representation for "No ellips/No CRS".
Definition: qgis.cpp:73
const double DEFAULT_SEGMENT_EPSILON
default snapping tolerance for segments
Definition: qgis.h:410
static const char * QGIS_DEV_VERSION
Definition: qgis.h:46
const int ELLPS_PREFIX_LEN
The length of the string "+ellps=".
Definition: qgis.h:389
static const float DEFAULT_MAPTOPIXEL_THRESHOLD
Default threshold between map coordinates and device coordinates for map2pixel simplification.
Definition: qgis.h:273
const long GEOCRS_ID
Magic number for a geographic coord sys in QGIS srs.db tbl_srs.srs_id.
Definition: qgis.h:381
Definition: qgis.h:68
CORE_EXPORT const QString GEOPROJ4
PROJ4 string that represents a geographic coord sys.
Definition: qgis.cpp:51
DataType
Raster data types.
Definition: qgis.h:204
void CORE_EXPORT qgsFree(void *ptr)
Frees the memory space pointed to by ptr.
Definition: qgis.cpp:205
Definition: qgis.h:66
unsigned long long qgssize
qgssize is used instead of size_t, because size_t is stdlib type, unknown by SIP, and it would be har...
Definition: qgis.h:420
static const double DEFAULT_SEARCH_RADIUS_MM
Identify search radius in mm.
Definition: qgis.h:270
static const char * QGIS_RELEASE_NAME
Definition: qgis.h:44
QString qgsDoubleToString(const double &a, const int &precision=17)
Definition: qgis.h:313
Definition: qgis.h:61
Definition: qgis.h:64
const double DEFAULT_POINT_SIZE
Magic number that determines the default point size for point symbols.
Definition: qgis.h:406
static bool isMultiType(WkbType type)
Definition: qgis.h:126
static int wkbDimensions(WkbType type)
Definition: qgis.h:139
const int USER_CRS_START_ID
Magick number that determines whether a projection crsid is a system (srs.db) or user (~/...
Definition: qgis.h:394
const long GEOSRID
Magic number for a geographic coord sys in POSTGIS SRID.
Definition: qgis.h:379
const double MINIMUM_POINT_SIZE
Magic number that determines the minimum allowable point size for point symbols.
Definition: qgis.h:404
bool qgsDoubleNearSig(double a, double b, int significantDigits=10)
Definition: qgis.h:330
const double DEFAULT_LINE_WIDTH
Definition: qgis.h:407
CORE_EXPORT const QString PROJECT_SCALES
Definition: qgis.cpp:67
Definition: qgis.h:158
const int LAT_PREFIX_LEN
The length of the string "+lat_1=".
Definition: qgis.h:391
void(*)() cast_to_fptr(void *p)
Definition: qgis.h:298
const int PROJ_PREFIX_LEN
The length of the string "+proj=".
Definition: qgis.h:387
QString qgsVsiPrefix(QString path)
Definition: qgis.cpp:242
double size
Definition: qgssvgcache.cpp:77
static const int QGIS_VERSION_INT
Definition: qgis.h:42
void CORE_EXPORT * qgsMalloc(size_t size)
Allocates size bytes and returns a pointer to the allocated memory.
Definition: qgis.cpp:175
static double DEFAULT_HIGHLIGHT_MIN_WIDTH_MM
Default highlight line/outline minimum width in mm.
Definition: qgis.h:286
bool qgsVariantGreaterThan(const QVariant &lhs, const QVariant &rhs)
Definition: qgis.cpp:237
const long GEO_EPSG_CRS_ID
Magic number for a geographic coord sys in EpsgCrsId ID format.
Definition: qgis.h:383
CORE_EXPORT const QString GEO_EPSG_CRS_AUTHID
Geographic coord sys from EPSG authority.
Definition: qgis.cpp:71
static WkbType multiType(WkbType type)
Definition: qgis.h:85
CORE_EXPORT const QString GEOWKT
Wkt string that represents a geographic coord sys.
Definition: qgis.cpp:54
static const char * featureType(WkbType type)
description strings for feature types
Definition: qgis.h:179
#define tr(sourceText)
Definition: qgsrasterrenderer.cpp:27