Merge commit 'd26ed8388f100a12996c0b92a98040ef2ba7fa8e' as 'ast'

1 files changed, 3703 insertions, 0 deletions

diff --git a/ast/stc.c b/ast/stc.c
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+++ b/ast/stc.c
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+/*
+*class++
+*  Name:
+*     Stc
+
+*  Purpose:
+*     Represents an instance of the IVOA STC class.
+
+*  Constructor Function:
+c     astStc
+f     AST_STC
+
+*  Description:
+*     The Stc class is an implementation of the IVOA STC class which forms
+*     part of the IVOA Space-Time Coordinate Metadata system. See:
+*
+*     http://hea-www.harvard.edu/~arots/nvometa/STC.html
+*
+*     The Stc class does not have a constructor function of its own, as it
+*     is simply a container class for a family of specialised sub-classes
+*     including StcCatalogEntryLocation, StcResourceProfile, StcSearchLocation
+*     and StcObsDataLocation.
+
+*  Inheritance:
+*     The Stc class inherits from the Region class.
+
+*  Attributes:
+*     In addition to those attributes common to all Regions, every
+*     Stc also has the following attributes:
+*
+*     - RegionClass: The class name of the encapsulated Region.
+
+*  Functions:
+c     In addition to those functions applicable to all Regions, the
+c     following functions may also be applied to all Stc's:
+f     In addition to those routines applicable to all Regions, the
+f     following routines may also be applied to all Stc's:
+*
+c     - astGetStcRegion: Get a pointer to the encapsulated Region
+f     - AST_GETSTCREGION: Get a pointer to the encapsulated Region
+c     - astGetStcCoord: Get information about an AstroCoords element
+f     - AST_GETSTCCOORD: Get information about an AstroCoords element
+c     - astGetStcNCoord: Returns the number of AstroCoords elements in an Stc
+f     - AST_GETSTCNCOORD: Returns the number of AstroCoords elements in an Stc
+
+*  Copyright:
+*     Copyright (C) 1997-2006 Council for the Central Laboratory of the
+*     Research Councils
+*     Copyright (C) 2008 Science & Technology Facilities Council.
+*     All Rights Reserved.
+
+*  Licence:
+*     This program is free software: you can redistribute it and/or
+*     modify it under the terms of the GNU Lesser General Public
+*     License as published by the Free Software Foundation, either
+*     version 3 of the License, or (at your option) any later
+*     version.
+*     
+*     This program is distributed in the hope that it will be useful,
+*     but WITHOUT ANY WARRANTY; without even the implied warranty of
+*     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*     GNU Lesser General Public License for more details.
+*     
+*     You should have received a copy of the GNU Lesser General
+*     License along with this program.  If not, see
+*     <http://www.gnu.org/licenses/>.
+
+*  Authors:
+*     DSB: David S. Berry (Starlink)
+
+*  History:
+*     23-NOV-2004 (DSB):
+*        Original version.
+*     14-FEB-2006 (DSB):
+*        Override astGetObjSize.
+*     13-MAR-2009 (DSB):
+*        Over-ride astRegBasePick.
+*class--
+*/
+
+/* Module Macros. */
+/* ============== */
+/* Set the name of the class we are implementing. This indicates to
+   the header files that define class interfaces that they should make
+   "protected" symbols available. */
+#define astCLASS Stc
+
+/* The number of components in an AstroCoords element which are described
+   using a Region within a KeyMap. */
+#define NREG 5
+
+/* Include files. */
+/* ============== */
+/* Interface definitions. */
+/* ---------------------- */
+
+#include "globals.h"             /* Thread-safe global data access */
+#include "error.h"               /* Error reporting facilities */
+#include "memory.h"              /* Memory allocation facilities */
+#include "object.h"              /* Base Object class */
+#include "unitmap.h"             /* Unit Mappings */
+#include "region.h"              /* Regions (parent class) */
+#include "channel.h"             /* I/O channels */
+#include "stc.h"                 /* Interface definition for this class */
+#include "keymap.h"              /* Lists of value/key pairs */
+#include "pointlist.h"           /* Individual points in a Frame */
+#include "ellipse.h"             /* Ellipses within a Frame */
+#include "interval.h"            /* Axis intervals within a Frame */
+#include "prism.h"               /* Extrusions into higher dimensions */
+
+/* Error code definitions. */
+/* ----------------------- */
+#include "ast_err.h"             /* AST error codes */
+
+/* C header files. */
+/* --------------- */
+#include <stdarg.h>
+#include <stddef.h>
+#include <string.h>
+#include <stdio.h>
+
+/* Module Variables. */
+/* ================= */
+
+/* Address of this static variable is used as a unique identifier for
+   member of this class. */
+static int class_check;
+
+/* Pointers to parent class methods which are extended by this class. */
+static AstMapping *(* parent_simplify)( AstMapping *, int * );
+static AstPointSet *(* parent_transform)( AstMapping *, AstPointSet *, int, AstPointSet *, int * );
+static AstRegion *(* parent_getdefunc)( AstRegion *, int * );
+static const char *(* parent_getattrib)( AstObject *, const char *, int * );
+static int (* parent_equal)( AstObject *, AstObject *, int * );
+static int (* parent_getobjsize)( AstObject *, int * );
+static int (* parent_getusedefs)( AstObject *, int * );
+static int (* parent_testattrib)( AstObject *, const char *, int * );
+static void (* parent_clearattrib)( AstObject *, const char *, int * );
+static void (* parent_setattrib)( AstObject *, const char *, int * );
+static void (* parent_setregfs)( AstRegion *, AstFrame *, int * );
+static void (*parent_regclearattrib)( AstRegion *, const char *, char **, int * );
+static void (*parent_regsetattrib)( AstRegion *, const char *, char **, int * );
+
+static void (* parent_clearnegated)( AstRegion *, int * );
+static void (* parent_clearclosed)( AstRegion *, int * );
+static void (* parent_clearfillfactor)( AstRegion *, int * );
+static void (* parent_clearmeshsize)( AstRegion *, int * );
+
+static void (* parent_setclosed)( AstRegion *, int, int * );
+static void (* parent_setfillfactor)( AstRegion *, double, int * );
+static void (* parent_setmeshsize)( AstRegion *, int, int * );
+static void (* parent_setnegated)( AstRegion *, int, int * );
+
+#if defined(THREAD_SAFE)
+static int (* parent_managelock)( AstObject *, int, int, AstObject **, int * );
+#endif
+
+/* The keys associated with each component of an AstroCoords element
+   within KeyMap */
+static const char *regkey[ NREG ] = { AST__STCERROR,
+                                      AST__STCRES,
+                                      AST__STCSIZE,
+                                      AST__STCPIXSZ,
+                                      AST__STCVALUE };
+
+/* The comments associated with each component of an AstroCoords element
+   within KeyMap */
+static const char *regcom[ NREG ] = { "AstroCoords error region",
+                                      "AstroCoords resolution region",
+                                      "AstroCoords size region",
+                                      "AstroCoords pixel size region",
+                                      "AstroCoords value region" };
+
+
+#ifdef THREAD_SAFE
+/* Define how to initialise thread-specific globals. */
+#define GLOBAL_inits \
+   globals->Class_Init = 0;
+
+/* Create the function that initialises global data for this module. */
+astMAKE_INITGLOBALS(Stc)
+
+/* Define macros for accessing each item of thread specific global data. */
+#define class_init astGLOBAL(Stc,Class_Init)
+#define class_vtab astGLOBAL(Stc,Class_Vtab)
+
+
+#include <pthread.h>
+
+
+#else
+
+
+/* Define the class virtual function table and its initialisation flag
+   as static variables. */
+static AstStcVtab class_vtab;   /* Virtual function table */
+static int class_init = 0;       /* Virtual function table initialised? */
+
+#endif
+
+/* External Interface Function Prototypes. */
+/* ======================================= */
+
+/* Prototypes for Private Member Functions. */
+/* ======================================== */
+static AstKeyMap *GetStcCoord( AstStc *, int, int * );
+static AstKeyMap *MakeAstroCoordsKeyMap( AstRegion *, AstKeyMap *, const char *, int * );
+static AstMapping *Simplify( AstMapping *, int * );
+static AstPointSet *RegBaseMesh( AstRegion *, int * );
+static AstPointSet *Transform( AstMapping *, AstPointSet *, int, AstPointSet *, int * );
+static AstRegion *GetDefUnc( AstRegion *, int * );
+static AstRegion *GetStcRegion( AstStc *, int * );
+static AstRegion *RegBasePick( AstRegion *this, int, const int *, int * );
+static const char *GetRegionClass( AstStc *, int * );
+static int Equal( AstObject *, AstObject *, int * );
+static int GetBounded( AstRegion *, int * );
+static int GetObjSize( AstObject *, int * );
+static int GetStcNCoord( AstStc *, int * );
+static int GetUseDefs( AstObject *, int * );
+static int Overlap( AstRegion *, AstRegion *, int * );
+static int OverlapX( AstRegion *, AstRegion *, int * );
+static int RegPins( AstRegion *, AstPointSet *, AstRegion *, int **, int * );
+static void Copy( const AstObject *, AstObject *, int * );
+static void Delete( AstObject *, int * );
+static void Dump( AstObject *, AstChannel *, int * );
+static void GetRegion( AstStc *, AstRegion **, int *, int * );
+static void RegBaseBox( AstRegion *, double *, double *, int * );
+static void RegClearAttrib( AstRegion *, const char *, char **, int * );
+static void RegSetAttrib( AstRegion *, const char *, char **, int * );
+static void SetRegFS( AstRegion *, AstFrame *, int * );
+
+static void ClearAttrib( AstObject *, const char *, int * );
+static const char *GetAttrib( AstObject *, const char *, int * );
+static void SetAttrib( AstObject *, const char *, int * );
+static int TestAttrib( AstObject *, const char *, int * );
+
+static void ClearClosed( AstRegion *, int * );
+static int GetClosed( AstRegion *, int * );
+static void SetClosed( AstRegion *, int, int * );
+static int TestClosed( AstRegion *, int * );
+
+static void ClearMeshSize( AstRegion *, int * );
+static int GetMeshSize( AstRegion *, int * );
+static void SetMeshSize( AstRegion *, int, int * );
+static int TestMeshSize( AstRegion *, int * );
+
+static void ClearFillFactor( AstRegion *, int * );
+static double GetFillFactor( AstRegion *, int * );
+static void SetFillFactor( AstRegion *, double, int * );
+static int TestFillFactor( AstRegion *, int * );
+
+static void ClearNegated( AstRegion *, int * );
+static int GetNegated( AstRegion *, int * );
+static void SetNegated( AstRegion *, int, int * );
+static int TestNegated( AstRegion *, int * );
+
+#if defined(THREAD_SAFE)
+static int ManageLock( AstObject *, int, int, AstObject **, int * );
+#endif
+
+/* Member functions. */
+/* ================= */
+static void ClearAttrib( AstObject *this_object, const char *attrib, int *status ) {
+/*
+*  Name:
+*     ClearAttrib
+
+*  Purpose:
+*     Clear an attribute value for a Stc.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     void ClearAttrib( AstObject *this, const char *attrib, int *status )
+
+*  Class Membership:
+*     Stc member function (over-rides the astClearAttrib protected
+*     method inherited from the Region class).
+
+*  Description:
+*     This function clears the value of a specified attribute for a
+*     Stc, so that the default value will subsequently be used.
+
+*  Parameters:
+*     this
+*        Pointer to the Stc.
+*     attrib
+*        Pointer to a null terminated string specifying the attribute
+*        name.  This should be in lower case with no surrounding white
+*        space.
+*     status
+*        Pointer to the inherited status variable.
+
+*/
+
+/* Local Variables: */
+   AstStc *this;                 /* Pointer to the Stc structure */
+   int len;                      /* Length of attrib string */
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* Obtain a pointer to the Stc structure. */
+   this = (AstStc *) this_object;
+
+/* Obtain the length of the "attrib" string. */
+   len = strlen( attrib );
+
+/* Check the attribute name and clear the appropriate attribute. */
+
+/* (none as yet) */
+/* ------------- */
+
+/* Read-only attributes. */
+/* --------------------- */
+/* Test if the attribute name matches any of the read-only attributes
+   of this class. If it does, then report an error. */
+   if ( !strcmp( attrib, "regionclass" ) ) {
+      astError( AST__NOWRT, "astClear: Invalid attempt to clear the \"%s\" "
+                "value for a %s.", status, attrib, astGetClass( this ) );
+      astError( AST__NOWRT, "This is a read-only attribute." , status);
+
+/* Not recognised. */
+/* --------------- */
+/* If the attribute is still not recognised, pass it on to the parent
+   method for further interpretation. */
+   } else {
+      (*parent_clearattrib)( this_object, attrib, status );
+   }
+}
+
+static int Equal( AstObject *this_object, AstObject *that_object, int *status ) {
+/*
+*  Name:
+*     Equal
+
+*  Purpose:
+*     Test if two Objects are equivalent.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     int Equal( AstObject *this_object, AstObject *that_object, int *status )
+
+*  Class Membership:
+*     Stc member function (over-rides the astEqual protected
+*     method inherited from the Region class).
+
+*  Description:
+*     This function returns a boolean result (0 or 1) to indicate whether
+*     two Stcs are equivalent.
+
+*  Parameters:
+*     this
+*        Pointer to the first Stc.
+*     that
+*        Pointer to the second Stc.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     One if the Stcs are equivalent, zero otherwise.
+
+*  Notes:
+*     - The Stcs are equivalent if their encapsulated Region are
+*     equivalent, and if they have the same boolean operation, negation
+*     and closed flags.
+*     - A value of zero will be returned if this function is invoked
+*     with the global status set, or if it should fail for any reason.
+*/
+
+/* Local Variables: */
+   AstStc *that;
+   AstStc *this;
+   int result;
+
+/* Initialise. */
+   result = 0;
+
+/* Check the global error status. */
+   if ( !astOK ) return result;
+
+/* Invoke the Equal method inherited from the parent Region class. This checks
+   that the Objects are both of the same class, and have the same Negated
+   and Closed flags (amongst other things). */
+   if( (*parent_equal)( this_object, that_object, status ) ) {
+
+/* Obtain pointers to the two Stc structures. */
+      this = (AstStc *) this_object;
+      that = (AstStc *) that_object;
+
+/* Test their encapsulated Region for equality. */
+      result = astEqual( this->region, that->region );
+   }
+
+/* If an error occurred, clear the result value. */
+   if ( !astOK ) result = 0;
+
+/* Return the result, */
+   return result;
+}
+
+/*
+*  Name:
+*     MAKE_SET
+
+*  Purpose:
+*     Define a function to set an attribute value for a Stc.
+
+*  Type:
+*     Private macro.
+
+*  Synopsis:
+*     #include "stc.h"
+*     MAKE_SET(attribute,lattribute,type)
+
+*  Class Membership:
+*     Defined by the Stc class.
+
+*  Description:
+*     This macro expands to an implementation of a private member function
+*     of the form:
+*
+*        static void Set<Attribute>( AstRegion *this, <Type> value )
+*
+*     that sets the value of a specified Region attribute in the parent
+*     Region structure and also in the encapsulated Region.
+
+*  Parameters:
+*     attribute
+*        Name of the attribute, as it appears in the function name.
+*     lattribute
+*        Name of the attribute, all in lower case.
+*     type
+*        The C type of the attribute.
+*/
+
+/* Define the macro. */
+#define MAKE_SET(attribute,lattribute,type) \
+static void Set##attribute( AstRegion *this_region, type value, int *status ) { \
+\
+/* Local Variables: */ \
+   AstStc *this;         /* Pointer to the Stc structure */ \
+\
+/* Check the global error status. */ \
+   if ( !astOK ) return; \
+\
+/* Use the parent method to set the value in the parent Region structure. */ \
+   (*parent_set##lattribute)( this_region, value, status ); \
+\
+/* Also set the value in the encapsulated Region. */ \
+   this = (AstStc *) this_region; \
+   astSet##attribute( this->region, value ); \
+}
+
+/* Use the above macro to create accessors for the MeshSize, Closed and
+   FillFactor attributes. */
+MAKE_SET(FillFactor,fillfactor,double)
+MAKE_SET(MeshSize,meshsize,int)
+MAKE_SET(Closed,closed,int)
+MAKE_SET(Negated,negated,int)
+
+/* Undefine the macro. */
+#undef MAKE_SET
+
+/*
+*  Name:
+*     MAKE_CLEAR
+
+*  Purpose:
+*     Define a function to clear an attribute value for a Stc.
+
+*  Type:
+*     Private macro.
+
+*  Synopsis:
+*     #include "stc.h"
+*     MAKE_CLEAR(attribute,lattribute)
+
+*  Class Membership:
+*     Defined by the Stc class.
+
+*  Description:
+*     This macro expands to an implementation of a private member function
+*     of the form:
+*
+*        static void Clear<Attribute>( AstRegion *this )
+*
+*     that sets the value of a specified Region attribute in the parent
+*     Region structure and also in the encapsulated Region.
+
+*  Parameters:
+*     attribute
+*        Name of the attribute, as it appears in the function name.
+*     lattribute
+*        Name of the attribute, all in lower case.
+*/
+
+/* Define the macro. */
+#define MAKE_CLEAR(attribute,lattribute) \
+static void Clear##attribute( AstRegion *this_region, int *status ) { \
+\
+/* Local Variables: */ \
+   AstStc *this;         /* Pointer to the Stc structure */ \
+\
+/* Check the global error status. */ \
+   if ( !astOK ) return; \
+\
+/* Use the parent method to clear the value in the parent Region structure. */ \
+   (*parent_clear##lattribute)( this_region, status ); \
+\
+/* Also clear the value in the encapsulated Region. */ \
+   this = (AstStc *) this_region; \
+   astClear##attribute( this->region ); \
+}
+
+/* Use the above macro to create accessors for the MeshSize, Closed and
+   FillFactor attributes. */
+MAKE_CLEAR(FillFactor,fillfactor)
+MAKE_CLEAR(MeshSize,meshsize)
+MAKE_CLEAR(Closed,closed)
+MAKE_CLEAR(Negated,negated)
+
+/* Undefine the macro. */
+#undef MAKE_CLEAR
+
+
+/*
+*  Name:
+*     MAKE_GET
+
+*  Purpose:
+*     Define a function to get an attribute value for a Stc.
+
+*  Type:
+*     Private macro.
+
+*  Synopsis:
+*     #include "stc.h"
+*     MAKE_GET(attribute,type,bad)
+
+*  Class Membership:
+*     Defined by the Stc class.
+
+*  Description:
+*     This macro expands to an implementation of a private member function
+*     of the form:
+*
+*        static <Type> Get<Attribute>( AstRegion *this )
+*
+*     that gets the value of a specified Region attribute from the encapsulated
+*     Region.
+
+*  Parameters:
+*     attribute
+*        Name of the attribute, as it appears in the function name.
+*     type
+*        The C type of the attribute.
+*     bad
+*        Value to return in caseof error.
+*/
+
+/* Define the macro. */
+#define MAKE_GET(attribute,type,bad) \
+static type Get##attribute( AstRegion *this_region, int *status ) { \
+\
+/* Local Variables: */ \
+   AstStc *this;         /* Pointer to the Stc structure */ \
+\
+/* Check the global error status. */ \
+   if ( !astOK ) return (bad); \
+\
+/* Get the value from the encapsulated Region. */ \
+   this = (AstStc *) this_region; \
+   return astGet##attribute( this->region ); \
+}
+
+/* Use the above macro to create accessors for the MeshSize, Closed and
+   FillFactor attributes. */
+MAKE_GET(FillFactor,double,AST__BAD)
+MAKE_GET(MeshSize,int,100)
+MAKE_GET(Closed,int,1)
+MAKE_GET(Negated,int,0)
+
+/* Undefine the macro. */
+#undef MAKE_GET
+
+/*
+*  Name:
+*     MAKE_TEST
+
+*  Purpose:
+*     Define a function to test an attribute value for a Stc.
+
+*  Type:
+*     Private macro.
+
+*  Synopsis:
+*     #include "stc.h"
+*     MAKE_TEST(attribute)
+
+*  Class Membership:
+*     Defined by the Stc class.
+
+*  Description:
+*     This macro expands to an implementation of a private member function
+*     of the form:
+*
+*        static int Test<Attribute>( AstRegion *this )
+*
+*     that test the value of a specified Region attribute from the encapsulated
+*     Region.
+
+*  Parameters:
+*     attribute
+*        Name of the attribute, as it appears in the function name.
+*     type
+*        The C type of the attribute.
+*/
+
+/* Define the macro. */
+#define MAKE_TEST(attribute) \
+static int Test##attribute( AstRegion *this_region, int *status ) { \
+\
+/* Local Variables: */ \
+   AstStc *this;         /* Pointer to the Stc structure */ \
+\
+/* Check the global error status. */ \
+   if ( !astOK ) return 0; \
+\
+/* Test the value from the encapsulated Region. */ \
+   this = (AstStc *) this_region; \
+   return astTest##attribute( this->region ); \
+}
+
+/* Use the above macro to create accessors for the MeshSize, Closed and
+   FillFactor attributes. */
+MAKE_TEST(FillFactor)
+MAKE_TEST(MeshSize)
+MAKE_TEST(Closed)
+MAKE_TEST(Negated)
+
+/* Undefine the macro. */
+#undef MAKE_TEST
+
+
+
+
+static int GetObjSize( AstObject *this_object, int *status ) {
+/*
+*  Name:
+*     GetObjSize
+
+*  Purpose:
+*     Return the in-memory size of an Object.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     int GetObjSize( AstObject *this, int *status )
+
+*  Class Membership:
+*     Stc member function (over-rides the astGetObjSize protected
+*     method inherited from the parent class).
+
+*  Description:
+*     This function returns the in-memory size of the supplied Stc,
+*     in bytes.
+
+*  Parameters:
+*     this
+*        Pointer to the Stc.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     The Object size, in bytes.
+
+*  Notes:
+*     - A value of zero will be returned if this function is invoked
+*     with the global status set, or if it should fail for any reason.
+*/
+
+/* Local Variables: */
+   AstStc *this;         /* Pointer to Stc structure */
+   int result;           /* Result value to return */
+   int i;                /* AstroCoords index */
+
+/* Initialise. */
+   result = 0;
+
+/* Check the global error status. */
+   if ( !astOK ) return result;
+
+/* Obtain a pointers to the Stc structure. */
+   this = (AstStc *) this_object;
+
+/* Invoke the GetObjSize method inherited from the parent class, and then
+   add on any components of the class structure defined by thsi class
+   which are stored in dynamically allocated memory. */
+   result = (*parent_getobjsize)( this_object, status );
+   result += astGetObjSize( this->region );
+
+   if( this->coord ) {
+      for( i = 0; i < this->ncoord; i++ ) {
+         result += astGetObjSize( this->coord[ i ] );
+      }
+      result += astTSizeOf( this->coord );
+   }
+
+/* If an error occurred, clear the result value. */
+   if ( !astOK ) result = 0;
+
+/* Return the result, */
+   return result;
+}
+
+static const char *GetAttrib( AstObject *this_object, const char *attrib, int *status ) {
+/*
+*  Name:
+*     GetAttrib
+
+*  Purpose:
+*     Get the value of a specified attribute for a Stc.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     const char *GetAttrib( AstObject *this, const char *attrib, int *status )
+
+*  Class Membership:
+*     Stc member function (over-rides the protected astGetAttrib
+*     method inherited from the Region class).
+
+*  Description:
+*     This function returns a pointer to the value of a specified
+*     attribute for a Stc, formatted as a character string.
+
+*  Parameters:
+*     this
+*        Pointer to the Stc.
+*     attrib
+*        Pointer to a null-terminated string containing the name of
+*        the attribute whose value is required. This name should be in
+*        lower case, with all white space removed.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     - Pointer to a null-terminated string containing the attribute
+*     value.
+
+*  Notes:
+*     - The returned string pointer may point at memory allocated
+*     within the Stc, or at static memory. The contents of the
+*     string may be over-written or the pointer may become invalid
+*     following a further invocation of the same function or any
+*     modification of the Stc. A copy of the string should
+*     therefore be made if necessary.
+*     - A NULL pointer will be returned if this function is invoked
+*     with the global error status set, or if it should fail for any
+*     reason.
+*/
+
+/* Local Variables: */
+   AstStc *this;                 /* Pointer to the Stc structure */
+   const char *result;           /* Pointer value to return */
+   int len;                      /* Length of attrib string */
+
+/* Initialise. */
+   result = NULL;
+
+/* Check the global error status. */
+   if ( !astOK ) return result;
+
+/* Obtain a pointer to the Stc structure. */
+   this = (AstStc *) this_object;
+
+/* Obtain the length of the attrib string. */
+   len = strlen( attrib );
+
+/* Compare "attrib" with each recognised attribute name in turn,
+   obtaining the value of the required attribute. If necessary, write
+   the value into "buff" as a null-terminated string in an appropriate
+   format.  Set "result" to point at the result string. */
+
+/* RegionClass. */
+/* ------------ */
+   if ( !strcmp( attrib, "regionclass" ) ) {
+      result = astGetClass( this->region );
+
+/* Not recognised. */
+/* --------------- */
+/* If the attribute name was not recognised, pass it on to the parent
+   method for further interpretation. */
+   } else {
+      result = (*parent_getattrib)( this_object, attrib, status );
+   }
+
+/* Return the result. */
+   return result;
+}
+
+static int GetBounded( AstRegion *this_region, int *status ) {
+/*
+*  Name:
+*     GetBounded
+
+*  Purpose:
+*     Is the Region bounded?
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     int GetBounded( AstRegion *this, int *status )
+
+*  Class Membership:
+*     Stc method (over-rides the astGetBounded method inherited from
+*     the Region class).
+
+*  Description:
+*     This function returns a flag indicating if the Region is bounded.
+*     The implementation provided by the base Region class is suitable
+*     for Region sub-classes representing the inside of a single closed
+*     curve (e.g. Circle, Ellipse, Box, etc). Other sub-classes (such as
+*     Stc, PointList, etc ) may need to provide their own implementations.
+
+*  Parameters:
+*     this
+*        Pointer to the Region.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     Non-zero if the Region is bounded. Zero otherwise.
+
+*/
+
+/* Local Variables: */
+   AstStc *this;              /* Pointer to Stc structure */
+   AstRegion *reg;            /* Pointer to the encapsulated Region */
+   int neg;                   /* Negated flag to use */
+   int neg_old;               /* Original Negated flag */
+   int result;                /* Returned result */
+
+/* Initialise */
+   result = 0;
+
+/* Check the global error status. */
+   if ( !astOK ) return result;
+
+/* Get a pointer to the Stc structure. */
+   this = (AstStc *) this_region;
+
+/* Get the encapsulated Region, and the Negated value which should be used
+   with it. The returned values take account of whether the supplied Stc has
+   itself been Negated or not. The returned Region represent a region within
+   the base Frame of the FrameSet encapsulated by the parent Region
+   structure. */
+   GetRegion( this, &reg, &neg, status );
+
+/* Temporarily set the Negated attribute to the required value.*/
+   neg_old = astGetNegated( reg );
+   astSetNegated( reg, neg );
+
+/* See if the encapsulated Region is bounded. */
+   result = astGetBounded( reg );
+
+/* Re-instate the original value for the Negated attribute of the
+   encapsulated Region. */
+   if( reg ) astSetNegated( reg, neg_old );
+
+/* Free resources. */
+   reg = astAnnul( reg );
+
+/* Return zero if an error occurred. */
+   if( !astOK ) result = 0;
+
+/* Return the required pointer. */
+   return result;
+}
+
+static AstRegion *GetDefUnc( AstRegion *this_region, int *status ) {
+/*
+*  Name:
+*     GetDefUnc
+
+*  Purpose:
+*     Obtain a pointer to the default uncertainty Region for a given Region.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     AstRegion *GetDefUnc( AstRegion *this )
+
+*  Class Membership:
+*     Stc method (over-rides the astGetDefUnc method inherited from
+*     the Region class).
+
+*     This function returns a pointer to a Region which represents the
+*     default uncertainty associated with a position on the boundary of the
+*     given  Region. The returned Region refers to the base Frame within the
+*     FrameSet encapsulated by the supplied Region.
+
+*  Parameters:
+*     this
+*        Pointer to the Region.
+
+*  Returned Value:
+*     A pointer to the Region. This should be annulled (using astAnnul)
+*     when no longer needed.
+
+*  Notes:
+*     - A NULL pointer will be returned if this function is invoked
+*     with the global error status set, or if it should fail for any
+*     reason.
+*/
+
+/* Local Variables: */
+   AstStc *this;              /* Pointer to the Stc structure */
+   AstRegion *result;         /* Returned pointer */
+
+/* Initialise */
+   result = NULL;
+
+/* Check the global error status. */
+   if ( !astOK ) return result;
+
+/* Get a pointer to the Stc structure. */
+   this = (AstStc *) this_region;
+
+/* If the encapsulated region has non-default uncertainty, use it as
+   the default uncertainty for the Cmpregion. Note, the current Frame of
+   an uncertainty Region is assumed to be the same as the base Frame in the
+   Stc. */
+   if( astTestUnc( this->region ) ) {
+      result = astGetUncFrm( this->region, AST__CURRENT );
+
+/* Otherwise, use the parent method to determine the default uncertainty. */
+   } else {
+      result = (* parent_getdefunc)( this_region, status );
+   }
+
+/* Return NULL if an error occurred. */
+   if( !astOK ) result = astAnnul( result );
+
+/* Return the required pointer. */
+   return result;
+}
+
+static void GetRegion( AstStc *this, AstRegion **reg, int *neg, int *status ) {
+/*
+*
+*  Name:
+*     GetRegion
+
+*  Purpose:
+*     Get the encapsulated Region of a Stc.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "region.h"
+*     void GetRegion( AstStc *this, AstRegion **reg, int *neg, int *status )
+
+*  Class Membership:
+*     Stc member function
+
+*  Description:
+*     This function returns a pointer to a Region which is equivalent to
+*     the supplied Stc. If the Stc has been negated, then the returned
+*     "negated" flag will be set such that it represents the negated Stc.
+*
+*     The current Frames in returned encapsulated Region will be equivalent
+*     to the base Frame in the FrameSet encapsulated by the parent Region
+*     structure.
+
+*  Parameters:
+*     this
+*        Pointer to the Stc.
+*     reg
+*        Address of a location to receive a pointer to the encapsulated
+*        Region. The current Frame in this region will be equivalent to
+*        the base Frame in the FrameSet
+*     neg
+*        The value of the Negated attribute to be used with reg.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Notes:
+*     - Any changes made to the encapsulated Region using the returned
+*     pointer will be reflected in the supplied Stc.
+
+*/
+
+/* Initialise */
+   if( reg ) *reg = NULL;
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* Return the component Region pointers. */
+   if( reg ) *reg = astClone( this->region );
+
+/* Initialise the other returned items. Note, the Stc initialiser stored a
+   deep copy of the supplied encapsulated Region, and so we do not
+   need to worry about attributes of the Region having been changed
+   after the creation of the Stc. This is different to the CmpMap
+   class which merely clones its supplied component pointers and so has
+   to save copies of the original Invert settings within the CmpMap
+   structure. */
+   if( neg ) *neg = astGetNegated( this->region );
+
+/* If the Stc has been inverted, we modify the boolean operator and
+   negation flags so that they reflect the inverted Stc. */
+   if( astGetNegated( this ) && neg ) *neg = *neg ? 0 : 1;
+}
+
+static const char *GetRegionClass( AstStc *this, int *status ){
+/*
+*+
+*  Name:
+*     astGetRegionClass
+
+*  Purpose:
+*     Get the value of a RegionClass attribute for a Stc.
+
+*  Type:
+*     Protected function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     const char *astGetRegionClass( AstStc *this )
+
+*  Class Membership:
+*     Stc virtual function
+
+*  Description:
+*     This function returns a pointer to the value of the RegionClass
+*     attribute for a Stc.
+
+*  Parameters:
+*     this
+*        Pointer to the Stc.
+
+*  Returned Value:
+*     - Pointer to a null-terminated string containing the attribute
+*     value.
+
+*  Notes:
+*     - The returned string pointer may point at memory allocated
+*     within the Stc, or at static memory. The contents of the
+*     string may be over-written or the pointer may become invalid
+*     following a further invocation of the same function or any
+*     modification of the Stc. A copy of the string should
+*     therefore be made if necessary.
+*     - A NULL pointer will be returned if this function is invoked
+*     with the global error status set, or if it should fail for any
+*     reason.
+*-
+*/
+
+/* Check the global error status. */
+   if ( !astOK ) return NULL;
+
+/* Obtain and return the class of the encapsulated Region. */
+   return astGetClass( ((AstStc *) this)->region );
+}
+
+
+static AstKeyMap *GetStcCoord( AstStc *this, int icoord, int *status ){
+/*
+*++
+*  Name:
+c     astGetStcCoord
+f     AST_GETSTCCOORD
+
+*  Purpose:
+*     Return information about an AstroCoords element stored in an Stc.
+
+*  Type:
+*     Public virtual function.
+
+*  Synopsis:
+c     #include "specframe.h"
+c     AstKeyMap *astGetStcCoord( AstStc *this, int icoord )
+f     RESULT = AST_GETSTCCOORD( THIS, ICOORD, STATUS )
+
+*  Class Membership:
+*     Stc method.
+
+*  Description:
+*     When any sub-class of Stc is created, the constructor function
+*     allows one or more AstroCoords elements to be stored within the Stc.
+*     This function allows any one of these AstroCoords elements to be
+*     retrieved. The format of the returned information is the same as
+*     that used to pass the original information to the Stc constructor.
+*     That is, the information is returned in a KeyMap structure
+*     containing elements with one or more of the keys given by symbolic
+*     constants AST__STCNAME, AST__STCVALUE, AST__STCERROR, AST__STCRES,
+*     AST__STCSIZE and AST__STCPIXSZ.
+*
+*     If the coordinate system represented by the Stc has been changed
+*     since it was created (for instance, by changing its System
+*     attribute), then the sizes and positions in the returned KeyMap
+*     will reflect the change in coordinate system.
+
+*  Parameters:
+c     this
+f     THIS = INTEGER (Given)
+*        Pointer to the Stc.
+c     icoord
+f     ICOORD = INTEGER (Given)
+*        The index of the AstroCoords element required. The first has index
+*        one. The number of AstroCoords elements in the Stc can be found using
+c        function astGetStcNcoord.
+f        function AST_GETSTCNCOORD.
+f     STATUS = INTEGER (Given and Returned)
+f        The global status.
+
+*  Returned Value:
+c     astGetStcCoord()
+f     AST_GETSTCCOORD = INTEGER
+*        A pointer to a new KeyMap containing the required information.
+
+*  Notes:
+*     - A null Object pointer (AST__NULL) will be returned if this
+c     function is invoked with the AST error status set, or if it
+f     function is invoked with STATUS set to an error value, or if it
+*     should fail for any reason.
+*--
+*/
+
+/* Local Variables: */
+   AstFrame *frm;
+   AstKeyMap *result;
+   AstMapping *map;
+   AstMapping *smap;
+   AstObject *obj;
+   AstRegion *reg;
+   AstRegion *rereg;
+   AstRegion *srereg;
+   int ikey;
+   int nc;
+
+/* Initialise. */
+   result = NULL;
+
+/* Check the global error status. */
+   if ( !astOK ) return result;
+
+/* Validate the supplied index. */
+   nc = astGetStcNCoord( this );
+   if( icoord < 1 || icoord > nc ) {
+      astError( AST__STCIND, "astGetStcCoord(%s): Supplied AstroCoords "
+                "index (%d) is invalid.", status, astGetClass( this ), icoord );
+
+      if( icoord < 1 ) {
+         astError( AST__STCIND, "The index of the first AstroCoord "
+                   "element is one, not zero." , status);
+      } else if( nc == 0 ) {
+         astError( AST__STCIND, "There are no AstroCoords elements in "
+                   "the supplied %s.", status, astGetClass( this ) );
+      } else if( nc == 1 ) {
+         astError( AST__STCIND, "There is 1 AstroCoords element in "
+                   "the supplied %s.", status, astGetClass( this ) );
+      } else {
+         astError( AST__STCIND, "There are %d AstroCoords elements in "
+                   "the supplied %s.", status, nc, astGetClass( this ) );
+      }
+
+/* If the index is OK, initialise the returned KeyMap to be a copy of the
+   KeyMap holding information about the required AstroCoords element.*/
+   } else {
+      result = astCopy( this->coord[ icoord - 1 ] );
+
+/* The Regions stored within this KeyMap describe regions within the base
+   Frame of the parent Region structure. If the Mapping from base to current
+   Frame in the parent Region structure is not a UnitMap, we need to
+   change these to represent regions within the current Frame of the
+   parent Region structure. */
+      map = astGetMapping( ((AstRegion *)this)->frameset,
+                           AST__BASE, AST__CURRENT );
+      smap = astSimplify( map );
+      frm = astGetFrame( ((AstRegion *)this)->frameset, AST__CURRENT );
+
+/* If the Frame represented by the Region has changed, erase the Names
+   element since they may no longer be correct. */
+      if( !astIsAUnitMap( smap ) ) astMapRemove( result, AST__STCNAME );
+
+/* Loop round keys for which a Region may be stored in the KeyMap. */
+      for( ikey = 0; ikey < NREG; ikey++ ) {
+
+/* If the KeyMap contains a Region for this key, get a pointer to it. */
+         if( astMapGet0A( result, regkey[ ikey ], &obj ) ){
+            reg = (AstRegion *) obj;
+
+/* Sets its RegionFS attribute so that the encapsulated FrameSet will be
+   included in any dump of the Region. This is needed since the returned
+   Region pointer will have no parent Region from which the FrameSet can
+   be determined. */
+            astSetRegionFS( reg, 1 );
+
+/* If necessary, remap the Region into the current Frame, and simplify. */
+            if( !astIsAUnitMap( smap ) ) {
+               rereg = astMapRegion( reg, smap, frm );
+               srereg = astSimplify( rereg );
+               rereg = astAnnul( rereg );
+            } else {
+               srereg = astClone( reg );
+            }
+
+/* Replace the Region in the KeyMap with the remapped Region. */
+            astMapPut0A( result, regkey[ ikey ], srereg, NULL );
+
+/* Free resources */
+            reg = astAnnul( reg );
+            srereg = astAnnul( srereg );
+         }
+      }
+
+      frm = astAnnul( frm );
+      map = astAnnul( map );
+      smap = astAnnul( smap );
+
+/* Annul the returned KeyMap if an error has occurred. */
+      if( !astOK ) result = astAnnul( result );
+   }
+
+/* Return the pointer */
+   return result;
+
+}
+
+static int GetStcNCoord( AstStc *this, int *status ){
+/*
+*++
+*  Name:
+c     astGetStcNCoord
+f     AST_GETSTCNCOORD
+
+*  Purpose:
+*     Return the number of AstroCoords elements stored in an Stc.
+
+*  Type:
+*     Public virtual function.
+
+*  Synopsis:
+c     #include "stc.h"
+c     int astGetStcNCoord( AstStc *this )
+f     RESULT = AST_GETSTCNCOORD( THIS, STATUS )
+
+*  Class Membership:
+*     Stc method.
+
+*  Description:
+*     This function returns the number of AstroCoords elements stored in
+*     an Stc.
+
+*  Parameters:
+c     this
+f     THIS = INTEGER (Given)
+*        Pointer to the Stc.
+f     STATUS = INTEGER (Given and Returned)
+f        The global status.
+
+*  Returned Value:
+c     astGetStcNCoord()
+f     AST_GETSTCNCOORD = INTEGER
+*        The number of  AstroCoords elements stored in the Stc.
+
+*  Notes:
+*     - Zero will be returned if this
+c     function is invoked with the AST error status set, or if it
+f     function is invoked with STATUS set to an error value, or if it
+*     should fail for any reason.
+*--
+*/
+
+/* Return the required value. */
+   return astOK ? this->ncoord : 0;
+
+}
+
+static AstRegion *GetStcRegion( AstStc *this, int *status ) {
+/*
+*++
+*  Name:
+c     astGetStcRegion
+f     AST_GETSTCREGION
+
+*  Purpose:
+*     Obtain a copy of the encapsulated Region within a Stc.
+
+*  Type:
+*     Public virtual function.
+
+*  Synopsis:
+c     #include "stc.h"
+c     AstRegion *astGetStcRegion( AstStc *this )
+f     RESULT = AST_GETSTCREGION( THIS, STATUS )
+
+*  Class Membership:
+*     Region method.
+
+*  Description:
+*     This function returns a pointer to a deep copy of the Region
+*     supplied when the Stc was created.
+
+*  Parameters:
+c     this
+f     THIS = INTEGER (Given)
+*        Pointer to the Stc.
+f     STATUS = INTEGER (Given and Returned)
+f        The global status.
+
+*  Returned Value:
+c     astGetStcRegion()
+f     AST_GETSTCREGION = INTEGER
+*        A pointer to a deep copy of the Region encapsulated within the
+*        supplied Stc.
+
+*  Notes:
+*     - A null Object pointer (AST__NULL) will be returned if this
+c     function is invoked with the AST error status set, or if it
+f     function is invoked with STATUS set to an error value, or if it
+*     should fail for any reason.
+*--
+*/
+
+/* Check the global error status. */
+   if ( !astOK ) return NULL;
+
+/* Return a pointer to a copy of the encapsulated Region. */
+   return astCopy( this->region );
+}
+
+static int GetUseDefs( AstObject *this_object, int *status ) {
+/*
+*  Name:
+*     GetUseDefs
+
+*  Purpose:
+*     Get the value of the UseDefs attribute for a Stc.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     int GetUseDefs( AstObject *this_object, int *status ) {
+
+*  Class Membership:
+*     Stc member function (over-rides the protected astGetUseDefs
+*     method inherited from the Region class).
+
+*  Description:
+*     This function returns the value of the UseDefs attribute for a
+*     Stc, supplying a suitable default.
+
+*  Parameters:
+*     this
+*        Pointer to the Stc.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     - The USeDefs value.
+*/
+
+/* Local Variables: */
+   AstStc *this;                 /* Pointer to the Stc structure */
+   int result;                   /* Value to return */
+
+/* Initialise. */
+   result = 0;
+
+/* Check the global error status. */
+   if ( !astOK ) return result;
+
+/* Obtain a pointer to the Stc structure. */
+   this = (AstStc *) this_object;
+
+/* If the UseDefs value for the Stc has been set explicitly, use the
+   Get method inherited from the parent Region class to get its value. */
+   if( astTestUseDefs( this ) ) {
+      result = (*parent_getusedefs)( this_object, status );
+
+/* Otherwise, supply a default value equal to the UseDefs value of the
+   encapsulated Region. */
+   } else {
+      result = astGetUseDefs( this->region );
+   }
+
+/* Return the result. */
+   return result;
+}
+
+void astInitStcVtab_(  AstStcVtab *vtab, const char *name, int *status ) {
+/*
+*+
+*  Name:
+*     astInitStcVtab
+
+*  Purpose:
+*     Initialise a virtual function table for a Stc.
+
+*  Type:
+*     Protected function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     void astInitStcVtab( AstStcVtab *vtab, const char *name )
+
+*  Class Membership:
+*     Stc vtab initialiser.
+
+*  Description:
+*     This function initialises the component of a virtual function
+*     table which is used by the Stc class.
+
+*  Parameters:
+*     vtab
+*        Pointer to the virtual function table. The components used by
+*        all ancestral classes will be initialised if they have not already
+*        been initialised.
+*     name
+*        Pointer to a constant null-terminated character string which contains
+*        the name of the class to which the virtual function table belongs (it
+*        is this pointer value that will subsequently be returned by the Object
+*        astClass function).
+*-
+*/
+
+/* Local Variables: */
+   astDECLARE_GLOBALS            /* Pointer to thread-specific global data */
+   AstObjectVtab *object;        /* Pointer to Object component of Vtab */
+   AstMappingVtab *mapping;      /* Pointer to Mapping component of Vtab */
+   AstRegionVtab *region;        /* Pointer to Region component of Vtab */
+
+/* Check the local error status. */
+   if ( !astOK ) return;
+
+/* Get a pointer to the thread specific global data structure. */
+   astGET_GLOBALS(NULL);
+
+/* Initialize the component of the virtual function table used by the
+   parent class. */
+   astInitRegionVtab( (AstRegionVtab *) vtab, name );
+
+/* Store a unique "magic" value in the virtual function table. This
+   will be used (by astIsAStc) to determine if an object belongs to
+   this class.  We can conveniently use the address of the (static)
+   class_check variable to generate this unique value. */
+   vtab->id.check = &class_check;
+   vtab->id.parent = &(((AstRegionVtab *) vtab)->id);
+
+/* Initialise member function pointers. */
+/* ------------------------------------ */
+/* Store pointers to the member functions (implemented here) that
+   provide virtual methods for this class. */
+
+   vtab->GetRegionClass = GetRegionClass;
+   vtab->GetStcRegion = GetStcRegion;
+   vtab->GetStcCoord = GetStcCoord;
+   vtab->GetStcNCoord = GetStcNCoord;
+
+/* Save the inherited pointers to methods that will be extended, and
+   replace them with pointers to the new member functions. */
+   object = (AstObjectVtab *) vtab;
+   mapping = (AstMappingVtab *) vtab;
+   region = (AstRegionVtab *) vtab;
+
+   parent_getobjsize = object->GetObjSize;
+   object->GetObjSize = GetObjSize;
+
+#if defined(THREAD_SAFE)
+   parent_managelock = object->ManageLock;
+   object->ManageLock = ManageLock;
+#endif
+
+   parent_clearattrib = object->ClearAttrib;
+   object->ClearAttrib = ClearAttrib;
+
+   parent_getattrib = object->GetAttrib;
+   object->GetAttrib = GetAttrib;
+
+   parent_setattrib = object->SetAttrib;
+   object->SetAttrib = SetAttrib;
+
+   parent_testattrib = object->TestAttrib;
+   object->TestAttrib = TestAttrib;
+
+   parent_transform = mapping->Transform;
+   mapping->Transform = Transform;
+
+   parent_simplify = mapping->Simplify;
+   mapping->Simplify = Simplify;
+
+   parent_setregfs = region->SetRegFS;
+   region->SetRegFS = SetRegFS;
+
+   parent_equal = object->Equal;
+   object->Equal = Equal;
+
+   parent_clearclosed = region->ClearClosed;
+   region->ClearClosed = ClearClosed;
+
+   parent_setclosed = region->SetClosed;
+   region->SetClosed = SetClosed;
+
+   region->TestClosed = TestClosed;
+   region->GetClosed = GetClosed;
+
+   parent_regsetattrib = region->RegSetAttrib;
+   region->RegSetAttrib = RegSetAttrib;
+
+   parent_regclearattrib = region->RegClearAttrib;
+   region->RegClearAttrib = RegClearAttrib;
+
+   parent_clearnegated = region->ClearNegated;
+   region->ClearNegated = ClearNegated;
+
+   parent_setnegated = region->SetNegated;
+   region->SetNegated = SetNegated;
+
+   region->TestNegated = TestNegated;
+   region->GetNegated = GetNegated;
+
+   parent_setmeshsize = region->SetMeshSize;
+   region->SetMeshSize = SetMeshSize;
+
+   parent_clearmeshsize = region->ClearMeshSize;
+   region->ClearMeshSize = ClearMeshSize;
+
+   region->TestMeshSize = TestMeshSize;
+   region->GetMeshSize = GetMeshSize;
+
+   parent_setfillfactor = region->SetFillFactor;
+   region->SetFillFactor = SetFillFactor;
+
+   parent_clearfillfactor = region->ClearFillFactor;
+   region->ClearFillFactor = ClearFillFactor;
+
+   region->TestFillFactor = TestFillFactor;
+   region->GetFillFactor = GetFillFactor;
+
+   parent_getusedefs = object->GetUseDefs;
+   object->GetUseDefs = GetUseDefs;
+
+   parent_getdefunc = region->GetDefUnc;
+   region->GetDefUnc = GetDefUnc;
+
+/* Store replacement pointers for methods which will be over-ridden by
+   new member functions implemented here. */
+   region->Overlap = Overlap;
+   region->OverlapX = OverlapX;
+   region->RegBaseBox = RegBaseBox;
+   region->RegBaseMesh = RegBaseMesh;
+   region->RegBasePick = RegBasePick;
+   region->RegPins = RegPins;
+   region->GetBounded = GetBounded;
+
+/* Declare the copy constructor, destructor and class dump function. */
+   astSetCopy( vtab, Copy );
+   astSetDelete( vtab, Delete );
+   astSetDump( vtab, Dump, "Stc", "An IVOA Space-Time-Coords object" );
+
+/* If we have just initialised the vtab for the current class, indicate
+   that the vtab is now initialised, and store a pointer to the class
+   identifier in the base "object" level of the vtab. */
+   if( vtab == &class_vtab ) {
+      class_init = 1;
+      astSetVtabClassIdentifier( vtab, &(vtab->id) );
+   }
+}
+
+static AstKeyMap *MakeAstroCoordsKeyMap( AstRegion *reg, AstKeyMap *coord,
+                                         const char *class, int *status ){
+/*
+*  Name:
+*     MakeAstroCoordsKeyMap
+
+*  Purpose:
+*     Create a new KeyMap holding Regions describing a supplied
+*     AstroCoords element.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     AstKeyMap *MakeAstroCoordsKeyMap( AstRegion *reg, AstKeyMap *coord,
+*                                       const char *class, int *status )
+
+*  Class Membership:
+*     Stc member function
+
+*  Description:
+*     This function returns a pointer to a new KeyMap containing elements
+*     which correspond to the components of an STC AstroCoords element.
+*     The element with key AST__STCNAME holds a vector of character
+*     strings containing the names associated with each of the axies.
+*     The other elements of the returned KeyMap such as AST__STCERROR,
+*     AST__STCRES, etc, hold pointers to Regions describing the error
+*     box, resolution, etc, in the Frame of the supplied Region "reg".
+
+*  Parameters:
+*     reg
+*        Pointer to the Region in which the AstroCoords is defined.
+*     coordId
+*        An ID (not a pointer) to a KeyMap defining a single <AstroCoords>
+*        element, having elements with keys given by constants AST__STCNAME,
+*        AST__STCVALUE, AST__STCERROR, AST__STCRES, AST__STCSIZE,
+*        AST__STCPIXSZ. Any of these elements may be omitted, but no other
+*        elements should be included. If supplied, the AST__STCNAME element
+*        should be a vector of character string pointers holding the "Name"
+*        item for each axis. Any other supplied elements should be scalar
+*        elements, each  holding a pointer to a Region describing the
+*        associated item of ancillary information (error, resolution, size,
+*        pixel size or value). These Regions should refer to the coordinate
+*        system represented by "region".
+*     class
+*        Pointer to a string holding the STC class name.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     - Pointer to the new KeyMap.
+
+*  Notes:
+*     - A NULL pointer will be returned if this function is invoked
+*     with the global error status set, or if it should fail for any
+*     reason.
+*/
+
+/* Local Variables: */
+   AstFrame *frm;                /* Pointer to current Frame */
+   AstFrameSet *fs;              /* Pointer to conversion FrameSet */
+   AstKeyMap *result;            /* Pointer value to return */
+   AstMapping *map;              /* Pointer to conversion Mapping */
+   AstObject *obj;               /* Pointer to Object stored in supplied KeyMap */
+   AstRegion *areg;              /* Pointer to remapped Region */
+   AstRegion *sareg;             /* Pointer to simplified remapped Region */
+   const char *key;              /* Current key */
+   int j;                        /* Index of key within KeyMap */
+   int naxes;                    /* Number of axes in region */
+   int nkey;                     /* Number of keys in supplied KeyMap */
+   int nv;                       /* Number of values in KeyMap element */
+   int type;                     /* Data type of entry */
+
+/* Initialise. */
+   result = NULL;
+
+/* Check the global error status. */
+   if( !astOK ) return result;
+
+/* Confirm it is a genuine KeyMap pointer. */
+   if( !astIsAKeyMap( coord ) && astOK ) {
+      astError( AST__STCKEY, "astInitStc(%s): Supplied pointer is for "
+                "a %s, not a KeyMap.", status, class, astGetClass( coord ) );
+   }
+
+/* Initialise the new KeyMap to be a copy of the supplied KeyMap. */
+   result = astCopy( coord );
+
+/* Check the supplied KeyMap is usable. */
+   naxes = astGetNaxes( reg );
+   nkey = astMapSize( result );
+   for( j = 0; j < nkey; j++ ) {
+      key = astMapKey( result, j );
+      if( key ) {
+         nv = astMapLength( result, key );
+         type = astMapType( result, key );
+
+/* Check no unknown keys are present in the KeyMap. */
+         if( strcmp( key, AST__STCNAME ) &&
+             strcmp( key, AST__STCVALUE ) &&
+             strcmp( key, AST__STCERROR ) &&
+             strcmp( key, AST__STCRES ) &&
+             strcmp( key, AST__STCSIZE ) &&
+             strcmp( key, AST__STCPIXSZ ) ) {
+            astError( AST__STCKEY, "astInitStc(%s): Unknown key "
+                      "\"%s\" supplied in an AstroCoords list.", status,
+                      class, key );
+            break;
+
+/* Check that the "Name" element is a vector of "naxes" strings. */
+         } else if( !strcmp( key, AST__STCNAME ) ) {
+            if( nv != naxes ) {
+               astError( AST__STCKEY, "astInitStc(%s): %d \"%s\" "
+                         "values supplied in an AstroCoords list, but "
+                         "the Stc has %d axes. ", status, class, nv, key,
+                         naxes );
+               break;
+
+            } else if( type != AST__STRINGTYPE ) {
+               astError( AST__STCKEY, "astInitStc(%s): The \"%s\" "
+                         "values supplied in an AstroCoords list are "
+                         "not character strings. ", status, class, key );
+               break;
+            }
+
+/* Check that all other elements are scalar. */
+         } else if( nv != 1 ) {
+            astError( AST__STCKEY, "astInitStc(%s): %d \"%s\" "
+                      "values supplied in an AstroCoords list, but "
+                      "only one is allowed. ", status, class, nv, key );
+            break;
+
+/* Check that all other elements are AST Object pointers. */
+         } else if( type != AST__OBJECTTYPE ) {
+            astError( AST__STCKEY, "astInitStc(%s): The \"%s\" "
+                      "value supplied in an AstroCoords list is "
+                      "not an AST Object pointer. ", status, class, key );
+            break;
+
+/* Check that the Object pointers are not NULL. */
+         } else {
+            astMapGet0A( result, key, &obj );
+            if( astOK ) {
+               if( !obj ) {
+                  astError( AST__STCKEY, "astInitStc(%s): The \"%s\" "
+                            "value supplied in an AstroCoords list is "
+                            "a NULL pointer. ", status, class, key );
+                  break;
+
+/* Check that the Object pointers are Region pointers. */
+               } else if( !astIsARegion( obj ) ){
+                  astError( AST__STCKEY, "astInitStc(%s): The \"%s\" "
+                            "value supplied in an AstroCoords list is "
+                            "a %s, not a Region. ", status, class, key,
+                            astGetClass(obj) );
+                  obj = astAnnul( obj );
+                  break;
+
+/* Check that the Region pointers can be converted to the coordinate
+   system represented by the supplied Region. */
+               } else {
+                  fs = astConvert( obj, reg, "" );
+                  if( !fs ) {
+                     obj = astAnnul( obj );
+                     astError( AST__STCKEY, "astInitStc(%s): The \"%s\" "
+                               "value supplied in an AstroCoords list "
+                               "cannot be converted to the coordinate "
+                               "system of its parent Stc object.", status, class,
+                               key );
+                     break;
+
+/* If necessary, map the Region into the same frame as the supplied
+   Region, and replace the Region in the returned KeyMap with the
+   remapped Region. Also set the RegionFS attribute to indicate that the
+   FrameSet in the Region does not need to be dumped if it contains a
+   UnitMap. */
+                  } else {
+                     map = astGetMapping( fs, AST__BASE, AST__CURRENT );
+                     if( !astIsAUnitMap( map ) ) {
+                        frm = astGetFrame( fs, AST__CURRENT );
+                        areg = astMapRegion( (AstRegion *) obj, map, frm );
+                        sareg = astSimplify( areg );
+                        astSetRegionFS( sareg, 0 );
+                        astMapPut0A( result, key, sareg, NULL );
+                        areg = astAnnul( areg );
+                        sareg = astAnnul( sareg );
+                        frm = astAnnul( frm );
+                     } else {
+                        astSetRegionFS( (AstRegion *) obj, 0 );
+                     }
+                     map = astAnnul( map );
+                     fs = astAnnul( fs );
+
+                  }
+                  obj = astAnnul( obj );
+               }
+            }
+         }
+      }
+   }
+
+/* Free the returned KeyMap if an error has occurred. */
+   if( !astOK ) result = astAnnul( result );
+
+/* Return the result */
+   return result;
+
+}
+
+#if defined(THREAD_SAFE)
+static int ManageLock( AstObject *this_object, int mode, int extra,
+                       AstObject **fail, int *status ) {
+/*
+*  Name:
+*     ManageLock
+
+*  Purpose:
+*     Manage the thread lock on an Object.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "object.h"
+*     AstObject *ManageLock( AstObject *this, int mode, int extra,
+*                            AstObject **fail, int *status )
+
+*  Class Membership:
+*     Stc member function (over-rides the astManageLock protected
+*     method inherited from the parent class).
+
+*  Description:
+*     This function manages the thread lock on the supplied Object. The
+*     lock can be locked, unlocked or checked by this function as
+*     deteremined by parameter "mode". See astLock for details of the way
+*     these locks are used.
+
+*  Parameters:
+*     this
+*        Pointer to the Object.
+*     mode
+*        An integer flag indicating what the function should do:
+*
+*        AST__LOCK: Lock the Object for exclusive use by the calling
+*        thread. The "extra" value indicates what should be done if the
+*        Object is already locked (wait or report an error - see astLock).
+*
+*        AST__UNLOCK: Unlock the Object for use by other threads.
+*
+*        AST__CHECKLOCK: Check that the object is locked for use by the
+*        calling thread (report an error if not).
+*     extra
+*        Extra mode-specific information.
+*     fail
+*        If a non-zero function value is returned, a pointer to the
+*        Object that caused the failure is returned at "*fail". This may
+*        be "this" or it may be an Object contained within "this". Note,
+*        the Object's reference count is not incremented, and so the
+*        returned pointer should not be annulled. A NULL pointer is
+*        returned if this function returns a value of zero.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*    A local status value:
+*        0 - Success
+*        1 - Could not lock or unlock the object because it was already
+*            locked by another thread.
+*        2 - Failed to lock a POSIX mutex
+*        3 - Failed to unlock a POSIX mutex
+*        4 - Bad "mode" value supplied.
+
+*  Notes:
+*     - This function attempts to execute even if an error has already
+*     occurred.
+*/
+
+/* Local Variables: */
+   AstStc *this;       /* Pointer to STC structure */
+   int i;              /* Loop count */
+   int result;         /* Returned status value */
+
+/* Initialise */
+   result = 0;
+
+/* Check the supplied pointer is not NULL. */
+   if( !this_object ) return result;
+
+/* Obtain a pointers to the STC structure. */
+   this = (AstStc *) this_object;
+
+/* Invoke the ManageLock method inherited from the parent class. */
+   if( !result ) result = (*parent_managelock)( this_object, mode, extra,
+                                                fail, status );
+
+/* Invoke the astManageLock method on any Objects contained within
+   the supplied Object. */
+   if( !result ) result = astManageLock( this->region, mode, extra, fail );
+   for( i = 0; i < this->ncoord; i++ ) {
+      if( !result ) result = astManageLock( this->coord[ i ], mode,
+                                            extra, fail );
+   }
+
+   return result;
+
+}
+#endif
+
+static int Overlap( AstRegion *this, AstRegion *that, int *status ){
+/*
+*  Name:
+*     Overlap
+
+*  Purpose:
+*     Test if two regions overlap each other.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     int Overlap( AstRegion *this, AstRegion *that, int *status )
+
+*  Class Membership:
+*     Stc member function (over-rides the astOverlap method inherited
+*     from the Region class).
+
+*  Description:
+*     This function returns an integer value indicating if the two
+*     supplied Regions overlap. The two Regions are converted to a commnon
+*     coordinate system before performing the check. If this conversion is
+*     not possible (for instance because the two Regions represent areas in
+*     different domains), then the check cannot be performed and a zero value
+*     is returned to indicate this.
+
+*  Parameters:
+*     this
+*        Pointer to the first Region.
+*     that
+*        Pointer to the second Region.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     astOverlap()
+*        A value indicating if there is any overlap between the two Regions.
+*        Possible values are:
+*
+*        0 - The check could not be performed because the second Region
+*            could not be mapped into the coordinate system of the first
+*            Region.
+*
+*        1 - There is no overlap between the two Regions.
+*
+*        2 - The first Region is completely inside the second Region.
+*
+*        3 - The second Region is completely inside the first Region.
+*
+*        4 - There is partial overlap between the two Regions.
+*
+*        5 - The Regions are identical.
+*
+*        6 - The second Region is the negation of the first Region.
+
+*  Notes:
+*     - The returned values 5 and 6 do not check the value of the Closed
+*     attribute in the two Regions.
+*     - A value of zero will be returned if this function is invoked with the
+*     AST error status set, or if it should fail for any reason.
+
+*/
+
+/* Check the inherited status. */
+   if ( !astOK ) return 0;
+
+/* Invoke the "astOverlap" method on the encapsulated Region. */
+   return astOverlap( ((AstStc *)this)->region, that );
+}
+
+static int OverlapX( AstRegion *that, AstRegion *this, int *status ){
+/*
+*  Name:
+*     OverlapX
+
+*  Purpose:
+*     Test if two regions overlap each other.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     int OverlapX( AstRegion *that, AstRegion *this )
+
+*  Class Membership:
+*     Stc member function (over-rides the astOverlapX method inherited
+*     from the Region class).
+
+*  Description:
+*     This function performs the processing for the public astOverlap
+*     method and has exactly the same interface except that the order
+*     of the two arguments is swapped. This is a trick to allow
+*     the astOverlap method to be over-ridden by derived classes on
+*     the basis of the class of either of its two arguments.
+*
+*     See the astOverlap method for details of the interface.
+
+*/
+
+/* Local Variables: */
+   int result;
+
+/* Check the inherited status. */
+   if ( !astOK ) return 0;
+
+/* Invoke the "astOverlapX" method on the encapsulated Region. */
+   result = astOverlap( ((AstStc *)that)->region, this );
+
+/* Swap the returned values 2 and 3 to take account of the swapping of
+   the regions.*/
+   if( result == 2 ) {
+      result = 3;
+   } else if( result == 3 ) {
+      result = 2;
+   }
+
+/* Return the result. */
+   return result;
+}
+
+static void RegBaseBox( AstRegion *this, double *lbnd, double *ubnd, int *status ){
+/*
+*  Name:
+*     RegBaseBox
+
+*  Purpose:
+*     Returns the bounding box of an un-negated Region in the base Frame of
+*     the encapsulated FrameSet.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     void RegBaseBox( AstRegion *this, double *lbnd, double *ubnd, int *status )
+
+*  Class Membership:
+*     Stc member function (over-rides the astRegBaseBox protected
+*     method inherited from the Region class).
+
+*  Description:
+*     This function returns the upper and lower axis bounds of a Region in
+*     the base Frame of the encapsulated FrameSet, assuming the Region
+*     has not been negated. That is, the value of the Negated attribute
+*     is ignored.
+
+*  Parameters:
+*     this
+*        Pointer to the Region.
+*     lbnd
+*        Pointer to an array in which to return the lower axis bounds
+*        covered by the Region in the base Frame of the encapsulated
+*        FrameSet. It should have at least as many elements as there are
+*        axes in the base Frame.
+*     ubnd
+*        Pointer to an array in which to return the upper axis bounds
+*        covered by the Region in the base Frame of the encapsulated
+*        FrameSet. It should have at least as many elements as there are
+*        axes in the base Frame.
+*     status
+*        Pointer to the inherited status variable.
+
+*/
+
+/* Check the global error status. */
+   if( !astOK ) return;
+
+/* Invoke the method on the encapsulated Region. */
+   astRegBaseBox( ((AstStc *)this)->region, lbnd, ubnd );
+}
+
+static AstPointSet *RegBaseMesh( AstRegion *this, int *status ){
+/*
+*  Name:
+*     RegBaseMesh
+
+*  Purpose:
+*     Create a new PointSet containing a mesh of points on the boundary of a
+*     Region in its base Frame.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     AstPointSet *astRegBaseMesh( AstRegion *this, int *status )
+
+*  Class Membership:
+*     Stc member function (over-rides the astRegBaseMesh protected
+*     method inherited from the Region class).
+
+*  Description:
+*     This function creates a new PointSet containing a mesh of points on the
+*     boundary of the Region. The points refer to the base Frame of
+*     the encapsulated FrameSet.
+
+*  Parameters:
+*     this
+*        Pointer to the Region.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     Pointer to the PointSet. Annul the pointer using astAnnul when it
+*     is no longer needed.
+
+*  Notes:
+*    - A NULL pointer is returned if an error has already occurred, or if
+*    this function should fail for any reason.
+
+*/
+
+/* Check the global error status. */
+   if( !astOK ) return NULL;
+
+/* Invoke the astRegMesh method on the encapsulated Region. This returns
+   a mesh in the current Frame of the encapsulated Region which is the same
+   as the base Frame of the Stc Region. */
+   return astRegMesh( ((AstStc *)this)->region );
+}
+
+static AstRegion *RegBasePick( AstRegion *this_region, int naxes,
+                               const int *axes, int *status ){
+/*
+*  Name:
+*     RegBasePick
+
+*  Purpose:
+*     Return a Region formed by picking selected base Frame axes from the
+*     supplied Region.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     AstRegion *RegBasePick( AstRegion *this, int naxes, const int *axes,
+*                             int *status )
+
+*  Class Membership:
+*     Stc member function (over-rides the astRegBasePick protected
+*     method inherited from the Region class).
+
+*  Description:
+*     This function attempts to return a Region that is spanned by selected
+*     axes from the base Frame of the encapsulated FrameSet of the supplied
+*     Region. This may or may not be possible, depending on the class of
+*     Region. If it is not possible a NULL pointer is returned.
+
+*  Parameters:
+*     this
+*        Pointer to the Region.
+*     naxes
+*        The number of base Frame axes to select.
+*     axes
+*        An array holding the zero-based indices of the base Frame axes
+*        that are to be selected.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     Pointer to the Region, or NULL if no region can be formed.
+
+*  Notes:
+*    - A NULL pointer is returned if an error has already occurred, or if
+*    this function should fail for any reason.
+*/
+
+/* Check the global error status. */
+   if ( !astOK ) return NULL;
+
+/* Invoke the astRegBaePick method on the encapsulated Region. */
+   return astRegBasePick( ((AstStc *)this_region)->region, naxes, axes );
+}
+
+static void RegClearAttrib( AstRegion *this_region, const char *attrib,
+                            char **base_attrib, int *status ) {
+/*
+*  Name:
+*     RegClearAttrib
+
+*  Purpose:
+*     Clear an attribute value for a Region.
+
+*  Type:
+*     Protected function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     void RegClearAttrib( AstRegion *this, const char *attrib,
+*                          char **base_attrib, int *status )
+
+*  Class Membership:
+*     Stc method (over-rides the astRegClearAttrib method inherited from
+*     the Region class).
+
+*  Description:
+*     This function clears the value of an attribute in both the base and
+*     current Frame in the FrameSet encapsulated within a Region, without
+*     remapping either Frame.
+*
+*     No error is reported if the attribute is not recognised by the base
+*     Frame.
+
+*  Parameters:
+*     this
+*        Pointer to the Region.
+*     attrib
+*        Pointer to a null terminated string containing an attribute name.
+*        NOTE, IT SHOULD BE ENTIRELY LOWER CASE.
+*     base_attrib
+*        Address of a location at which to return a pointer to the null
+*        terminated string holding the name of the attribute which was
+*        cleared in the base Frame of the encapsulated FrameSet. This may
+*        differ from the supplied name if the supplied name contains an axis
+*        index and the current->base Mapping in the FrameSet produces an
+*        axis permutation. The returned pointer should be freed using
+*        astFree when no longer needed. A NULL pointer may be supplied in
+*        which case no pointer is returned.
+*     status
+*        Pointer to the inherited status variable.
+
+*/
+
+/* Local Variables: */
+   AstStc *this;
+   char *batt;
+   int rep;
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* Get a pointer to the Stc  structure. */
+   this = (AstStc *) this_region;
+
+/* Use the RegClearAttrib method inherited from the parent class to clear
+   the attribute in the current and base Frames in the FrameSet encapsulated
+   by the parent Region structure. */
+   (*parent_regclearattrib)( this_region, attrib, &batt, status );
+
+/* Now clear the base Frame attribute in the encapsulated Region (the current
+   Frame within the encapsulated Region is equivalent to the base Frame in the
+   parent Region structure). Annul any "attribute unknown" error that results
+   from attempting to do this. */
+   if( astOK ) {
+      rep = astReporting( 0 );
+      astRegClearAttrib( this->region, batt, NULL );
+      if( astStatus == AST__BADAT ) astClearStatus;
+      astReporting( rep );
+   }
+
+/* If required, return the base Frame attribute name, otherwise free it. */
+   if( base_attrib ) {
+      *base_attrib = batt;
+   } else {
+      batt = astFree( batt );
+   }
+}
+
+static int RegPins( AstRegion *this, AstPointSet *pset, AstRegion *unc,
+                    int **mask, int *status ){
+/*
+*  Name:
+*     RegPins
+
+*  Purpose:
+*     Check if a set of points fall on the boundary of a given Stc.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     int RegPins( AstRegion *this, AstPointSet *pset, AstRegion *unc,
+*                  int **mask, int *status )
+
+*  Class Membership:
+*     Stc member function (over-rides the astRegPins protected
+*     method inherited from the Region class).
+
+*  Description:
+*     This function returns a flag indicating if the supplied set of
+*     points all fall on the boundary of the given Stc.
+*
+*     Some tolerance is allowed, as specified by the uncertainty Region
+*     stored in the supplied Stc "this", and the supplied uncertainty
+*     Region "unc" which describes the uncertainty of the supplied points.
+
+*  Parameters:
+*     this
+*        Pointer to the Stc.
+*     pset
+*        Pointer to the PointSet. The points are assumed to refer to the
+*        base Frame of the FrameSet encapsulated by "this".
+*     unc
+*        Pointer to a Region representing the uncertainties in the points
+*        given by "pset". The Region is assumed to represent the base Frame
+*        of the FrameSet encapsulated by "this". Zero uncertainity is assumed
+*        if NULL is supplied.
+*     mask
+*        Pointer to location at which to return a pointer to a newly
+*        allocated dynamic array of ints. The number of elements in this
+*        array is equal to the value of the Npoint attribute of "pset".
+*        Each element in the returned array is set to 1 if the
+*        corresponding position in "pset" is on the boundary of the Region
+*        and is set to zero otherwise. A NULL value may be supplied
+*        in which case no array is created. If created, the array should
+*        be freed using astFree when no longer needed.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     Non-zero if the points all fall on the boundary of the given
+*     Region, to within the tolerance specified. Zero otherwise.
+
+*/
+
+/* Check the global error status. */
+   if( !astOK ) return 0;
+
+/* Invoke the method on the encapsulated Region. */
+   return astRegPins( ((AstStc *)this)->region, pset, unc, mask );
+}
+
+static void RegSetAttrib( AstRegion *this_region, const char *setting,
+                          char **base_setting, int *status ) {
+/*
+*  Name:
+*     RegSetAttrib
+
+*  Purpose:
+*     Set an attribute value for a Region.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     void RegSetAttrib( AstRegion *this, const char *setting,
+*                        char **base_setting, int *status )
+
+*  Class Membership:
+*     Stc method (over-rides the astRegSetAttrib method inherited from
+*     the Region class).
+
+*  Description:
+*     This function assigns an attribute value to both the base and
+*     current Frame in the FrameSet encapsulated within a Region, without
+*     remapping either Frame.
+*
+*     No error is reported if the attribute is not recognised by the base
+*     Frame.
+
+*  Parameters:
+*     this
+*        Pointer to the Region.
+*     setting
+*        Pointer to a null terminated attribute setting string. NOTE, IT
+*        SHOULD BE ENTIRELY LOWER CASE. The supplied string will be
+*        interpreted using the public interpretation implemented by
+*        astSetAttrib. This can be different to the interpretation of the
+*        protected accessor functions. For instance, the public
+*        interpretation of an unqualified floating point value for the
+*        Epoch attribute is to interpet the value as a gregorian year,
+*        but the protected interpretation is to interpret the value as an
+*        MJD.
+*     base_setting
+*        Address of a location at which to return a pointer to the null
+*        terminated attribute setting string which was applied to the
+*        base Frame of the encapsulated FrameSet. This may differ from
+*        the supplied setting if the supplied setting contains an axis
+*        index and the current->base Mapping in the FrameSet produces an
+*        axis permutation. The returned pointer should be freed using
+*        astFree when no longer needed. A NULL pointer may be supplied in
+*        which case no pointer is returned.
+*     status
+*        Pointer to the inherited status variable.
+
+*/
+
+/* Local Variables: */
+   AstKeyMap *keymap;
+   AstObject *obj;
+   AstRegion *reg;
+   AstStc *this;
+   char *bset;
+   int i;
+   int ikey;
+   int rep;
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* Get a pointer to the Stc structure. */
+   this = (AstStc *) this_region;
+
+/* Use the RegSetAttrib method inherited from the parent class to apply the
+   setting to the current and base Frames in the FrameSet encapsulated by the
+   parent Region structure. */
+   (*parent_regsetattrib)( this_region, setting, &bset, status );
+
+/* Now apply the base Frame setting to the encapsulated Region (the current
+   Frame within the encapsulated Region is equivalent to the base Frame in the
+   parent Region structure). Annul any "attribute unknown" error that results
+   from attempting to do this. Also do any AstroCoords in the Stc. */
+   if( astOK ) {
+      rep = astReporting( 0 );
+      astRegSetAttrib( this->region, bset, NULL );
+      if( astStatus == AST__BADAT ) astClearStatus;
+
+/* Loop round all AstroCoords elements. */
+      for( i = 0; i < this->ncoord; i++ ) {
+
+/* Get a pointer to the KeyMap holding a description of the current
+   AstroCoords element. */
+         keymap = this->coord[ i ];
+
+/* Loop round all the elements of this KeyMap which may hold a Region
+   pointer. */
+         for( ikey = 0; ikey < NREG; ikey++ ) {
+
+/* If the KeyMap contains a Region for this key, get a pointer to it. */
+            if( astMapGet0A( keymap, regkey[ ikey ], &obj ) ){
+               reg = (AstRegion *) obj;
+
+/* Modify it by applying the attribute setting. */
+               astRegSetAttrib( reg, bset, NULL );
+               if( astStatus == AST__BADAT ) astClearStatus;
+
+/* Annul the pointer. */
+               reg = astAnnul( reg );
+            }
+         }
+      }
+
+      astReporting( rep );
+   }
+
+/* If required, return the base Frame setting string, otherwise free it. */
+   if( base_setting ) {
+      *base_setting = bset;
+   } else {
+      bset = astFree( bset );
+   }
+}
+
+static void SetAttrib( AstObject *this_object, const char *setting, int *status ) {
+/*
+*  Name:
+*     SetAttrib
+
+*  Purpose:
+*     Set an attribute value for a Stc.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     void SetAttrib( AstObject *this, const char *setting, int *status )
+
+*  Class Membership:
+*     Stc member function (over-rides the astSetAttrib method inherited
+*     from the Region class).
+
+*  Description:
+*     This function assigns an attribute value for a Stc, the
+*     attribute and its value being specified by means of a string of
+*     the form:
+*
+*        "attribute= value "
+*
+*     Here, "attribute" specifies the attribute name and should be in
+*     lower case with no white space present. The value to the right
+*     of the "=" should be a suitable textual representation of the
+*     value to be assigned and this will be interpreted according to
+*     the attribute's data type.  White space surrounding the value is
+*     only significant for string attributes.
+
+*  Parameters:
+*     this
+*        Pointer to the Stc.
+*     setting
+*        Pointer to a null terminated string specifying the new attribute
+*        value.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Notes:
+*     - This function uses one-based axis numbering so that it is
+*     suitable for external (public) use.
+*/
+
+/* Local Vaiables: */
+   AstStc *this;                 /* Pointer to the Stc structure */
+   int len;                      /* Length of setting string */
+   int nc;                       /* Number of characters read by astSscanf */
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* Obtain a pointer to the Stc structure. */
+   this = (AstStc *) this_object;
+
+/* Obtain the length of the setting string. */
+   len = strlen( setting );
+
+/* Test for each recognised attribute in turn, using "astSscanf" to parse the
+   setting string and extract the attribute value (or an offset to it in the
+   case of string values). In each case, use the value set in "nc" to check
+   that the entire string was matched. Once a value has been obtained, use the
+   appropriate method to set it. */
+
+/* (none as yet) */
+
+/* Read-only attributes. */
+/* --------------------- */
+/* Define a macro to see if the setting string matches any of the
+   read-only attributes of this class. */
+#define MATCH(attrib) \
+        ( nc = 0, ( 0 == astSscanf( setting, attrib "=%*[^\n]%n", &nc ) ) && \
+                  ( nc >= len ) )
+
+/* Use this macro to report an error if a read-only attribute has been
+   specified. */
+   if ( MATCH( "regionclass" ) ) {
+      astError( AST__NOWRT, "astSet: The setting \"%s\" is invalid for a %s.", status,
+                setting, astGetClass( this ) );
+      astError( AST__NOWRT, "This is a read-only attribute." , status);
+
+/* Not recognised. */
+/* --------------- */
+/* If the attribute is still not recognised, pass it on to the parent
+   method for further interpretation. */
+   } else {
+      (*parent_setattrib)( this_object, setting, status );
+   }
+
+/* Undefine macros local to this function. */
+#undef MATCH
+}
+
+static void SetRegFS( AstRegion *this_region, AstFrame *frm, int *status ) {
+/*
+*  Name:
+*     SetRegFS
+
+*  Purpose:
+*     Stores a new FrameSet in a Region
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     void SetRegFS( AstRegion *this_region, AstFrame *frm, int *status )
+
+*  Class Membership:
+*     Stc method (over-rides the astSetRegFS method inherited from
+*     the Region class).
+
+*  Description:
+*     This function creates a new FrameSet and stores it in the supplied
+*     Region. The new FrameSet contains two copies of the supplied
+*     Frame, connected by a UnitMap.
+
+*  Parameters:
+*     this
+*        Pointer to the Region.
+*     frm
+*        The Frame to use.
+*     status
+*        Pointer to the inherited status variable.
+
+*/
+
+/* Local Variables: */
+   AstRegion *creg;        /* Pointer to encapsulated Region structure */
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* Invoke the parent method to store the FrameSet in the parent Region
+   structure. */
+   (* parent_setregfs)( this_region, frm, status );
+
+/* If the encapsulated Region has a dummy FrameSet use this method
+   recursively to give it the same FrameSet. */
+   creg = ((AstStc *) this_region )->region;
+   if( creg && !astGetRegionFS( creg ) ) astSetRegFS( creg, frm );
+
+}
+
+static AstMapping *Simplify( AstMapping *this_mapping, int *status ) {
+/*
+*  Name:
+*     Simplify
+
+*  Purpose:
+*     Simplify a Region.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "region.h"
+*     AstMapping *Simplify( AstMapping *this, int *status )
+
+*  Class Membership:
+*     Stc method (over-rides the astSimplify method inherited from
+*     the Region class).
+
+*  Description:
+*     This function simplifies a Stc to eliminate redundant
+*     computational steps, or to merge separate steps which can be
+*     performed more efficiently in a single operation.
+
+*  Parameters:
+*     this
+*        Pointer to the original Region.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     A new pointer to the (possibly simplified) Region.
+
+*  Notes:
+*     - A NULL pointer value will be returned if this function is
+*     invoked with the AST error status set, or if it should fail for
+*     any reason.
+*/
+
+/* Local Variables: */
+   AstFrame *frm;                /* Current Frame */
+   AstKeyMap *keymap;            /* KeyMap holding stroCoords element */
+   AstMapping *map;              /* Base->current Mapping */
+   AstObject *obj;               /* Pointer to object retrieved from keymap */
+   AstRegion *newreg;            /* New encapsulated Region */
+   AstRegion *reg;               /* AstroCoords Region pointer */
+   AstRegion *treg;              /* Temporary Region pointer */
+   AstStc *stc;                  /* Returned Stc Structure. */
+   AstStc *temp;                 /* Temporary Stc pointer */
+   int i;                        /* Index of current AstroCoords element */
+   int ikey;                     /* Index of key to be tested */
+
+/* Check the global error status. */
+   if ( !astOK ) return NULL;
+
+/* Invoke the Simplify method of the parent Region class. This simplifies
+   the FrameSet and uncertainty Region in the parent Region structure. */
+   stc = (AstStc *) (AstRegion *) (* parent_simplify)( this_mapping, status );
+
+/* If the Stc is negated, we can perform a simplication by transferring
+   the negated state from the Stc itself to the encapsulated Region. */
+   if( astGetNegated( stc ) ) {
+
+/* Ensure that modifying "stc" will not modify the supplied Stc, by
+   creating a copy of the supplied Stc, if this has not already been done. */
+      if( stc == (AstStc *) this_mapping ) {
+         temp = (AstStc *) astCopy( stc );
+         (void) astAnnul( stc );
+         stc = temp;
+      }
+
+/* Modify "temp" by negating both the Stc structure and its encapsulated
+   Region. */
+      astNegate( stc );
+      astNegate( stc->region );
+
+   }
+
+/* Get the base->current Mapping from the parent Region structure, and
+   the current Frame. */
+   map = astGetMapping( ((AstRegion *) stc)->frameset, AST__BASE, AST__CURRENT );
+   frm = astGetFrame( ((AstRegion *) stc)->frameset, AST__CURRENT );
+
+/* We may be able to perform some more simplication on the encapsulated
+   Region itself. If the above mapping is not a unit map, remap the
+   encapsulated Region into the current Frame of the parent Region structure
+   and simplify it. This transfers complication from the Mapping in the
+   parent Region structure to the encapsulated Region. */
+   if( !astIsAUnitMap( map ) ) {
+      treg = astMapRegion( stc->region, map, frm );
+      newreg = astSimplify( treg );
+      treg = astAnnul( treg );
+
+/* If the base->current Mapping in the parent Region structure is a unit
+   map, simplification of the whole Stc is possible if the encapsulated
+   Region (without any remapping) can be simplied. */
+   } else {
+      newreg = astSimplify( stc->region );
+   }
+
+/* If the encapsulated Region has been changed, store it in the returned
+   Stc. */
+   if( newreg != stc->region ) {
+
+/* Ensure that modifying "stc" will not modify the supplied Stc, by
+   creating a copy of the supplied Stc, if this has not already been done. */
+      if( stc == (AstStc *) this_mapping ) {
+         temp = (AstStc *) astCopy( stc );
+         (void) astAnnul( stc );
+         stc = temp;
+      }
+
+/* Store the new region in "stc", annulling the existing Region. */
+      if( stc ) {
+         (void) astAnnul( stc->region );
+         stc->region = astClone( newreg );
+      }
+
+/* The encapsulated Region now represents an area in the current Frame
+   represented by the supplied Stc. Since the encapsulated Region is
+   defined as being in the base Frame of the FrameSet in the parent
+   Region structure, the parent FrameSet should just be a UnitMap. Modify
+   it appropriately (if it not already a UnitMap). */
+      if( !astIsAUnitMap( map ) ) astSetRegFS( stc, frm );
+   }
+
+/* Free resources */
+   newreg = astAnnul( newreg );
+
+/* Now we do a similar process on any Regions held within an AstroCoords
+   elements. Loop round all AstroCoords elements. */
+   if( stc ) {
+      for( i = 0; i < stc->ncoord; i++ ) {
+
+/* Get a pointewr to the KeyMap holding a description of the current
+   AstroCoords element. */
+         keymap = stc->coord[ i ];
+
+/* Loop round all the elements of this KeyMap which may hold a Region
+   pointer. */
+         for( ikey = 0; ikey < NREG; ikey++ ) {
+
+/* If the KeyMap contains a Region for this key, get a pointer to it. */
+            if( astMapGet0A( keymap, regkey[ ikey ], &obj ) ){
+               reg = (AstRegion *) obj;
+
+/* We have two tasks now, firstly to ensure that this AstroCoords Region
+   describes an area in the base Frame of the FrameSet in the parent
+   Region structure (which may have been changed by the earlier
+   simplications performed by this function), and secondly, to attempt to
+   simplify the Region.
+
+   The Stc structure addressed by the "stc" pointer will have a current
+   Frame given by "frm". This will also be its base Frame, and the
+   base->current Mapping will consequently be a UnitMap. The Mapping from
+   the original base Frame to the new base Frame is given by "map". Unless
+   this is a UnitMap, we need to remap the Region.*/
+               if( !astIsAUnitMap( map ) ) {
+                  treg = astMapRegion( reg, map, frm );
+               } else {
+                  treg = astClone( reg );
+               }
+
+/* Now attempt to simplify the Region.*/
+               newreg = astSimplify( treg );
+
+/* If the Region has been changed by either of these steps, we need to
+   store the modified Region back in the "stc" structure which is being
+   returned. But we need to be careful we do not modify the supplied Stc
+   structure. */
+               if( newreg != reg ) {
+
+                  if( stc == (AstStc *) this_mapping ) {
+                     temp = astCopy( stc );
+                     (void) astAnnul( stc );
+                     stc = temp;
+                     keymap = temp->coord[ i ];
+                  }
+
+                  astMapPut0A( keymap, regkey[ ikey ], newreg, regcom[ ikey ] );
+
+               }
+
+/* Free resources */
+               reg = astAnnul( reg );
+               treg = astAnnul( treg );
+               newreg = astAnnul( newreg );
+
+            }
+         }
+      }
+   }
+
+/* Free resources */
+   map = astAnnul( map );
+   frm = astAnnul( frm );
+
+/* If an error occurred, annul the returned Mapping. */
+   if ( !astOK ) stc = astAnnul( stc );
+
+/* Return the result. */
+   return (AstMapping *) stc;
+}
+
+static int TestAttrib( AstObject *this_object, const char *attrib, int *status ) {
+/*
+*  Name:
+*     TestAttrib
+
+*  Purpose:
+*     Test if a specified attribute value is set for a Stc.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     int TestAttrib( AstObject *this, const char *attrib, int *status )
+
+*  Class Membership:
+*     Stc member function (over-rides the astTestAttrib protected
+*     method inherited from the Region class).
+
+*  Description:
+*     This function returns a boolean result (0 or 1) to indicate whether
+*     a value has been set for one of a Stc's attributes.
+
+*  Parameters:
+*     this
+*        Pointer to the Stc.
+*     attrib
+*        Pointer to a null terminated string specifying the attribute
+*        name.  This should be in lower case with no surrounding white
+*        space.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     One if a value has been set, otherwise zero.
+
+*  Notes:
+*     - This function uses one-based axis numbering so that it is
+*     suitable for external (public) use.
+*     - A value of zero will be returned if this function is invoked
+*     with the global status set, or if it should fail for any reason.
+*/
+
+/* Local Variables: */
+   AstStc *this;                 /* Pointer to the Stc structure */
+   int len;                      /* Length of attrib string */
+   int result;                   /* Result value to return */
+
+/* Initialise. */
+   result = 0;
+
+/* Check the global error status. */
+   if ( !astOK ) return result;
+
+/* Obtain a pointer to the Stc structure. */
+   this = (AstStc *) this_object;
+
+/* Obtain the length of the attrib string. */
+   len = strlen( attrib );
+
+/* Check the attribute name and test the appropriate attribute. */
+
+/* Read-only attributes. */
+/* --------------------- */
+/* Test if the attribute name matches any of the read-only attributes
+   of this class. If it does, then return zero. */
+   if ( !strcmp( attrib, "regionclass" ) ) {
+      result = 0;
+
+/* Not recognised. */
+/* --------------- */
+/* If the attribute is still not recognised, pass it on to the parent
+   method for further interpretation. */
+   } else {
+      result = (*parent_testattrib)( this_object, attrib, status );
+   }
+
+/* Return the result, */
+   return result;
+}
+
+static AstPointSet *Transform( AstMapping *this_mapping, AstPointSet *in,
+                               int forward, AstPointSet *out, int *status ) {
+/*
+*  Name:
+*     Transform
+
+*  Purpose:
+*     Apply a Stc to transform a set of points.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     AstPointSet *Transform( AstMapping *this, AstPointSet *in,
+*                             int forward, AstPointSet *out, int *status )
+
+*  Class Membership:
+*     Stc member function (over-rides the astTransform method inherited
+*     from the Region class).
+
+*  Description:
+*     This function takes a Stc and a set of points encapsulated in a
+*     PointSet and transforms the points so as to apply the required Region.
+*     This implies applying each of the Stc's encapsulated Region in turn,
+*     either in series or in parallel.
+
+*  Parameters:
+*     this
+*        Pointer to the Stc.
+*     in
+*        Pointer to the PointSet associated with the input coordinate values.
+*     forward
+*        A non-zero value indicates that the forward coordinate transformation
+*        should be applied, while a zero value requests the inverse
+*        transformation.
+*     out
+*        Pointer to a PointSet which will hold the transformed (output)
+*        coordinate values. A NULL value may also be given, in which case a
+*        new PointSet will be created by this function.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     Pointer to the output (possibly new) PointSet.
+
+*  Notes:
+*     -  A null pointer will be returned if this function is invoked with the
+*     global error status set, or if it should fail for any reason.
+*     -  The number of coordinate values per point in the input PointSet must
+*     match the number of coordinates for the Stc being applied.
+*     -  If an output PointSet is supplied, it must have space for sufficient
+*     number of points and coordinate values per point to accommodate the
+*     result. Any excess space will be ignored.
+*/
+
+/* Local Variables: */
+   AstPointSet *ps;              /* Pointer to PointSet */
+   AstPointSet *pset_tmp;        /* Pointer to PointSet holding base Frame positions*/
+   AstPointSet *result;          /* Pointer to output PointSet */
+   AstRegion *reg;               /* Pointer to encapsulated Region */
+   AstStc *this;                 /* Pointer to the Stc structure */
+   double **ptr;                 /* Pointer to axis values */
+   double **ptr_out;             /* Pointer to output coordinate data */
+   int coord;                    /* Zero-based index for coordinates */
+   int good;                     /* Is the point inside the Stc? */
+   int ncoord_out;               /* No. of coordinates per output point */
+   int ncoord_tmp;               /* No. of coordinates per base Frame point */
+   int neg;                      /* Negated value for encapsulated Region */
+   int neg_old;                  /* Original Negated flag */
+   int npoint;                   /* No. of points */
+   int point;                    /* Loop counter for points */
+   int rep;                      /* Original error reporting status */
+   int status_value;                   /* AST status value */
+
+/* Initialise. */
+   result = NULL;
+
+/* Check the global error status. */
+   if ( !astOK ) return result;
+
+/* Get a Pointer to the Stc structure */
+   this = (AstStc *) this_mapping;
+
+/* Get the encapsulated Region, and the Negated value which should be used
+   with it. The returned values take account of whether the supplied Stc has
+   itself been Negated or not. The returned Region represent a region within
+   the base Frame of the FrameSet encapsulated by the parent Region
+   structure. */
+   GetRegion( this, &reg, &neg, status );
+
+/* Temporarily set the Negated attribute to the required value.*/
+   neg_old = astGetNegated( reg );
+   astSetNegated( reg, neg );
+
+/* Apply the parent mapping using the stored pointer to the Transform member
+   function inherited from the parent Region class. This function validates
+   all arguments and generates an output PointSet if necessary, containing
+   a copy of the input PointSet. */
+   result = (*parent_transform)( this_mapping, in, forward, out, status );
+
+/* We will now extend the parent astTransform method by performing the
+   calculations needed to generate the output coordinate values. */
+
+/* First use the encapsulated FrameSet in the parent Region structure to
+   transform the supplied positions from the current Frame in the
+   encapsulated FrameSet (the Frame represented by the Stc), to the
+   base Frame (the Frame in which the encapsulated Region are defined). Note,
+   the returned pointer may be a clone of the "in" pointer, and so we
+   must be carefull not to modify the contents of the returned PointSet. */
+   pset_tmp = astRegTransform( this, in, 0, NULL, NULL );
+
+/* Now transform this PointSet using the encapsulated Region. */
+   ps = astTransform( reg, pset_tmp, 0, NULL );
+
+/* Determine the numbers of points and coordinates per point for these base
+   Frame PointSets and obtain pointers for accessing the base Frame and output
+   coordinate values. */
+   npoint = astGetNpoint( pset_tmp );
+   ncoord_tmp = astGetNcoord( pset_tmp );
+   ptr = astGetPoints( ps );
+   ncoord_out = astGetNcoord( result );
+   ptr_out = astGetPoints( result );
+
+/* Perform coordinate arithmetic. */
+/* ------------------------------ */
+   if ( astOK ) {
+
+      for ( point = 0; point < npoint; point++ ) {
+         good = 0;
+
+         for ( coord = 0; coord < ncoord_tmp; coord++ ) {
+            if( ptr[ coord ][ point ] != AST__BAD ) {
+               good = 1;
+               break;
+            }
+         }
+
+         if( !good ) {
+            for ( coord = 0; coord < ncoord_out; coord++ ) {
+               ptr_out[ coord ][ point ] = AST__BAD;
+            }
+         }
+      }
+   }
+
+/* Re-instate the original value for the Negated attribute of the
+   encapsulated Region. Do this even if an error has occurred. */
+   status_value = astStatus;
+   astClearStatus;
+   rep = astReporting( 0 );
+   if( reg ) astSetNegated( reg, neg_old );
+   astReporting( rep );
+   astSetStatus( status_value );
+
+/* Free resources. */
+   reg = astAnnul( reg );
+   ps = astAnnul( ps );
+   pset_tmp = astAnnul( pset_tmp );
+
+/* If an error occurred, clean up by deleting the output PointSet (if
+   allocated by this function) and setting a NULL result pointer. */
+   if ( !astOK ) {
+      if ( !out ) result = astDelete( result );
+      result = NULL;
+   }
+
+/* Return a pointer to the output PointSet. */
+   return result;
+}
+
+
+/* Stc Attributes: */
+/* =============== */
+
+/*
+*att++
+*  Name:
+*     RegionClass
+
+*  Purpose:
+*     The AST class name of the Region encapsulated within an Stc
+
+*  Type:
+*     Public attribute.
+
+*  Synopsis:
+*     String, read-only.
+
+*  Description:
+*     This is a read-only attribute giving the AST class name of the
+*     Region encapsulated within an Stc (that is, the class of the Region
+*     which was supplied when the Stc was created).
+
+*  Applicability:
+*     Stc
+*        All Stc objects this attribute.
+*att--
+*/
+
+/* Copy constructor. */
+/* ----------------- */
+static void Copy( const AstObject *objin, AstObject *objout, int *status ) {
+/*
+*  Name:
+*     Copy
+
+*  Purpose:
+*     Copy constructor for Stc objects.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     void Copy( const AstObject *objin, AstObject *objout, int *status )
+
+*  Description:
+*     This function implements the copy constructor for Stc objects.
+
+*  Parameters:
+*     objin
+*        Pointer to the object to be copied.
+*     objout
+*        Pointer to the object being constructed.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     void
+
+*  Notes:
+*     -  This constructor makes a deep copy, including a copy of the component
+*     Regions within the Stc.
+*/
+
+/* Local Variables: */
+   AstStc *in;                /* Pointer to input Stc */
+   AstStc *out;               /* Pointer to output Stc */
+   int i;                     /* AstroCoords index */
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* Obtain pointers to the input and output Stcs. */
+   in = (AstStc *) objin;
+   out = (AstStc *) objout;
+
+/* For safety, start by clearing any references to the input component
+   Regions, etc,  from the output Stc. */
+   out->region = NULL;
+   out->coord = NULL;
+   out->ncoord = 0;
+
+/* Make a copy of the Region and store a pointer to it in the output Stc
+   structure. */
+   out->region = astCopy( in->region );
+
+/* Copy any memory holding AstroCoords values */
+   if( in->coord && in->ncoord ) {
+      out->ncoord = in->ncoord;
+      out->coord = astMalloc( sizeof(AstKeyMap *) * (size_t)in->ncoord );
+      if( out->coord ) {
+         for( i = 0; i < in->ncoord; i++ ) {
+            out->coord[ i ] = astCopy( in->coord[ i ] );
+         }
+      }
+   }
+}
+
+/* Destructor. */
+/* ----------- */
+static void Delete( AstObject *obj, int *status ) {
+/*
+*  Name:
+*     Delete
+
+*  Purpose:
+*     Destructor for Stc objects.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     void Delete( AstObject *obj, int *status )
+
+*  Description:
+*     This function implements the destructor for Stc objects.
+
+*  Parameters:
+*     obj
+*        Pointer to the object to be deleted.
+*     status
+*        Pointer to the inherited status variable.
+
+*  Returned Value:
+*     void
+
+*  Notes:
+*     This function attempts to execute even if the global error status is
+*     set.
+*/
+
+/* Local Variables: */
+   AstStc *this;              /* Pointer to Stc */
+   int i;                     /* AstroCoords index */
+
+/* Obtain a pointer to the Stc structure. */
+   this = (AstStc *) obj;
+
+/* Annul the pointer to the encapsulated Region. */
+   this->region = astAnnul( this->region );
+
+/* Free any memory holding AstroCoords values */
+   if( this->coord ) {
+      for( i = 0; i < this->ncoord; i++ ) {
+         this->coord[ i ] = astAnnul( this->coord[ i ] );
+      }
+      this->coord = astFree( this->coord );
+   }
+}
+
+/* Dump function. */
+/* -------------- */
+static void Dump( AstObject *this_object, AstChannel *channel, int *status ) {
+/*
+*  Name:
+*     Dump
+
+*  Purpose:
+*     Dump function for Stc objects.
+
+*  Type:
+*     Private function.
+
+*  Synopsis:
+*     void Dump( AstObject *this, AstChannel *channel, int *status )
+
+*  Description:
+*     This function implements the Dump function which writes out data
+*     for the Stc class to an output Channel.
+
+*  Parameters:
+*     this
+*        Pointer to the Stc whose data are being written.
+*     channel
+*        Pointer to the Channel to which the data are being written.
+*     status
+*        Pointer to the inherited status variable.
+*/
+
+/* Local Constants: */
+#define COMMENT_LEN 150          /* Maximum length of a comment string */
+#define KEY_LEN 50               /* Maximum length of a keyword */
+
+/* Local Variables: */
+   AstStc *this;                 /* Pointer to the Stc structure */
+   char comment[ COMMENT_LEN + 1 ]; /* Buffer for comment string */
+   char key[ KEY_LEN + 1 ];      /* Buffer for keyword string */
+   int ico;                      /* Loop counter for KeyMaps */
+
+/* Check the global error status. */
+   if ( !astOK ) return;
+
+/* Obtain a pointer to the Stc structure. */
+   this = (AstStc *) this_object;
+
+/* Write out values representing the instance variables for the Stc
+   class.  Accompany these with appropriate comment strings, possibly
+   depending on the values being written.*/
+
+/* In the case of attributes, we first use the appropriate (private)
+   Test...  member function to see if they are set. If so, we then use
+   the (private) Get... function to obtain the value to be written
+   out.
+
+   For attributes which are not set, we use the astGet... method to
+   obtain the value instead. This will supply a default value
+   (possibly provided by a derived class which over-rides this method)
+   which is more useful to a human reader as it corresponds to the
+   actual default attribute value.  Since "set" will be zero, these
+   values are for information only and will not be read back. */
+
+/* Encapsulated Region. */
+/* -------------------- */
+   astWriteObject( channel, "Region", 1, 1, this->region,
+                   "STC Region" );
+
+/* AstroCoords info */
+/* ---------------- */
+   astWriteInt( channel, "Ncoord", ( this->ncoord != 0 ), 0, this->ncoord,
+                "Number of AstroCoords elements" );
+
+   for ( ico = 1; ico <= this->ncoord; ico++ ) {
+      (void) sprintf( key, "Coord%d", ico );
+      (void) sprintf( comment, "AstroCoords number %d", ico );
+      astWriteObject( channel, key, 1, 1, this->coord[ ico - 1 ],
+                      comment );
+   }
+
+/* Undefine macros local to this function. */
+#undef COMMENT_LEN
+#undef KEY_LEN
+}
+
+/* Standard class functions. */
+/* ========================= */
+/* Implement the astIsAStc and astCheckStc functions using the
+   macros defined for this purpose in the "object.h" header file. */
+astMAKE_ISA(Stc,Region)
+astMAKE_CHECK(Stc)
+
+AstStc *astInitStc_( void *mem, size_t size, int init, AstStcVtab *vtab,
+                     const char *name, AstRegion *region, int ncoords,
+                     AstKeyMap **coords, int *status ) {
+/*
+*+
+*  Name:
+*     astInitStc
+
+*  Purpose:
+*     Initialise a Stc.
+
+*  Type:
+*     Protected function.
+
+*  Synopsis:
+*     #include "stc.h"
+*      AstStc *astInitStc( void *mem, size_t size, int init, AstStcVtab *vtab,
+*                          const char *name, AstRegion *region, int ncoords,
+*                          AstKeyMap **coords )
+
+*  Class Membership:
+*     Stc initialiser.
+
+*  Description:
+*     This function is provided for use by class implementations to initialise
+*     a new Stc object. It allocates memory (if necessary) to
+*     accommodate the Stc plus any additional data associated with the
+*     derived class. It then initialises a Stc structure at the start
+*     of this memory. If the "init" flag is set, it also initialises the
+*     contents of a virtual function table for a Stc at the start of
+*     the memory passed via the "vtab" parameter.
+
+*  Parameters:
+*     mem
+*        A pointer to the memory in which the Stc is to be initialised.
+*        This must be of sufficient size to accommodate the Stc data
+*        (sizeof(Stc)) plus any data used by the derived class. If a
+*        value of NULL is given, this function will allocate the memory itself
+*        using the "size" parameter to determine its size.
+*     size
+*        The amount of memory used by the Stc (plus derived class
+*        data). This will be used to allocate memory if a value of NULL is
+*        given for the "mem" parameter. This value is also stored in the
+*        Stc structure, so a valid value must be supplied even if not
+*        required for allocating memory.
+*     init
+*        A logical flag indicating if the Stc's virtual function table
+*        is to be initialised. If this value is non-zero, the virtual function
+*        table will be initialised by this function.
+*     vtab
+*        Pointer to the start of the virtual function table to be associated
+*        with the new Stc.
+*     name
+*        Pointer to a constant null-terminated character string which contains
+*        the name of the class to which the new object belongs (it is this
+*        pointer value that will subsequently be returned by the Object
+*        astClass function).
+*     region
+*        Pointer to the Region represented by the Stc.
+*     ncoords
+*        Number of KeyMap pointers supplied in "coords". Can be zero.
+*        Ignored if "coords" is NULL.
+*     coords
+*        Pointer to an array of "ncoords" KeyMap pointers, or NULL if
+*        "ncoords" is zero. Each KeyMap defines defines a single <AstroCoords>
+*        element, and should have elements with keys given by constants
+*        AST__STCNAME, AST__STCVALUE, AST__STCERROR, AST__STCRES, AST__STCSIZE,
+*        AST__STCPIXSZ. Any of these elements may be omitted, but no other
+*        elements should be included. If supplied, the AST__STCNAME element
+*        should be a vector of character string pointers holding the "Name"
+*        item for each axis. Any other supplied elements should be scalar
+*        elements, each  holding a pointer to a Region describing the
+*        associated item of ancillary information (error, resolution, size,
+*        pixel size or value). These Regions should describe a volume within
+*        the coordinate system represented by "region".
+
+*  Returned Value:
+*     A pointer to the new Stc.
+
+*  Notes:
+*     -  A null pointer will be returned if this function is invoked with the
+*     global error status set, or if it should fail for any reason.
+*-
+*/
+
+/* Local Variables: */
+   AstMapping *frm;              /* Current Frame in supplied Stc */
+   AstMapping *map;              /* Base -> Current Mapping in supplied Stc */
+   AstRegion *reg;               /* Copy of supplied Region */
+   AstStc *new;                  /* Pointer to new Stc */
+   int i;                        /* AstroCoords index */
+
+/* Check the global status. */
+   if ( !astOK ) return NULL;
+
+/* If necessary, initialise the virtual function table. */
+   if ( init ) astInitStcVtab( vtab, name );
+
+/* Initialise. */
+   new = NULL;
+
+/* If the supplied Region is an Stc, create a new Region by mapping the
+   encapsulated Region within the supplied Stc into the current Frame of the
+   Stc. */
+   if( astIsAStc( region ) ) {
+      map = astGetMapping( region->frameset, AST__BASE, AST__CURRENT );
+      frm = astGetFrame( region->frameset, AST__CURRENT );
+      reg = astMapRegion( ((AstStc *) region)->region, map, frm );
+      frm = astAnnul( frm );
+      map = astAnnul( map );
+
+/* Otherwise, just take a copy of the supplied Region. */
+   } else {
+      reg = astCopy( region );
+   }
+
+/* Initialise a Region structure (the parent class) as the first component
+   within the Stc structure, allocating memory if necessary. A NULL
+   PointSet is suppled as the encapsulated Region will perform the function
+   of defining the Region shape. The base Frame of the FrameSet in the
+   parent Region structure will be the same as the current Frames of the
+   FrameSets in the two encapsulated Region. */
+   if ( astOK ) {
+      new = (AstStc *) astInitRegion( mem, size, 0, (AstRegionVtab *) vtab,
+                                      name, reg, NULL, NULL );
+
+/* Initialise the Stc data. */
+/* --------------------------- */
+/* Store a pointer to the encapsulated Region. */
+      new->region = astClone( reg );
+
+/* No AstroCoords info as yet. */
+      new->ncoord = 0;
+      new->coord = NULL;
+
+/* Transfer attributes from the encapsulated region to the parent region. */
+     astRegOverlay( new, reg, 1 );
+     if( astTestIdent( reg ) ) astSetIdent( new, astGetIdent( reg ) );
+
+/* If the base->current Mapping in the FrameSet within the encapsulated Region
+   is a UnitMap, then the FrameSet does not need to be included in the
+   Dump of the new Stc. Set the RegionFS attribute of the encapsulated
+   Region to zero to flag this. Note, we do this after the previous class
+   to astRegOverlay because we do not want this zero value for RegionFS to
+   be copied into the new Stc object. */
+      astSetRegionFS( reg, 0 );
+
+/* For each supplied AstroCoords, create a new KeyMap holding Regions
+   representing the various elements of the AstroCoords, and store the
+   new KeyMap in the Stc structure. */
+      if( coords && ncoords > 0 ) {
+         new->ncoord = ncoords;
+         new->coord = astMalloc( sizeof( AstKeyMap *)*(size_t) ncoords );
+         if( new->coord ) {
+            for( i = 0; i < ncoords; i++ ) {
+               new->coord[ i ] = MakeAstroCoordsKeyMap( reg, coords[ i ],
+                                                        name, status );
+            }
+         }
+      }
+
+/* If an error occurred, clean up deleting the new object. */
+      if ( !astOK ) new = astDelete( new );
+   }
+
+/* Free resources */
+   reg = astAnnul( reg );
+
+/* Return a pointer to the new object. */
+   return new;
+}
+
+AstStc *astLoadStc_( void *mem, size_t size, AstStcVtab *vtab,
+                     const char *name, AstChannel *channel, int *status ) {
+/*
+*+
+*  Name:
+*     astLoadStc
+
+*  Purpose:
+*     Load a Stc.
+
+*  Type:
+*     Protected function.
+
+*  Synopsis:
+*     #include "stc.h"
+*     AstStc *astLoadStc( void *mem, size_t size, AstStcVtab *vtab,
+*                         const char *name, AstChannel *channel )
+
+*  Class Membership:
+*     Stc loader.
+
+*  Description:
+*     This function is provided to load a new Stc using data read
+*     from a Channel. It first loads the data used by the parent class
+*     (which allocates memory if necessary) and then initialises a
+*     Stc structure in this memory, using data read from the input
+*     Channel.
+*
+*     If the "init" flag is set, it also initialises the contents of a
+*     virtual function table for a Stc at the start of the memory
+*     passed via the "vtab" parameter.
+
+*  Parameters:
+*     mem
+*        A pointer to the memory into which the Stc is to be
+*        loaded.  This must be of sufficient size to accommodate the
+*        Stc data (sizeof(Stc)) plus any data used by derived
+*        classes. If a value of NULL is given, this function will
+*        allocate the memory itself using the "size" parameter to
+*        determine its size.
+*     size
+*        The amount of memory used by the Stc (plus derived class
+*        data).  This will be used to allocate memory if a value of
+*        NULL is given for the "mem" parameter. This value is also
+*        stored in the Stc structure, so a valid value must be
+*        supplied even if not required for allocating memory.
+*
+*        If the "vtab" parameter is NULL, the "size" value is ignored
+*        and sizeof(AstStc) is used instead.
+*     vtab
+*        Pointer to the start of the virtual function table to be
+*        associated with the new Stc. If this is NULL, a pointer to
+*        the (static) virtual function table for the Stc class is
+*        used instead.
+*     name
+*        Pointer to a constant null-terminated character string which
+*        contains the name of the class to which the new object
+*        belongs (it is this pointer value that will subsequently be
+*        returned by the astGetClass method).
+*
+*        If the "vtab" parameter is NULL, the "name" value is ignored
+*        and a pointer to the string "Stc" is used instead.
+
+*  Returned Value:
+*     A pointer to the new Stc.
+
+*  Notes:
+*     - A null pointer will be returned if this function is invoked
+*     with the global error status set, or if it should fail for any
+*     reason.
+*-
+*/
+
+
+/* Local Constants: */
+   astDECLARE_GLOBALS            /* Pointer to thread-specific global data */
+#define KEY_LEN 50               /* Maximum length of a keyword */
+
+/* Local Variables: */
+   AstFrame *f1;                 /* Base Frame in parent Region */
+   AstObject *obj;               /* Pointer to Object retrieved from KeyMap */
+   AstRegion *creg;              /* Pointer to encapsulated Region */
+   AstStc *new;                  /* Pointer to the new Stc */
+   char key[ KEY_LEN + 1 ];      /* Buffer for keyword string */
+   int ico;                      /* Loop counter for AstroCoords */
+   int ikey;                     /* Index of KeyMap */
+
+/* Get a pointer to the thread specific global data structure. */
+   astGET_GLOBALS(channel);
+
+/* Initialise. */
+   new = NULL;
+
+/* Check the global error status. */
+   if ( !astOK ) return new;
+
+/* If a NULL virtual function table has been supplied, then this is
+   the first loader to be invoked for this Stc. In this case the
+   Stc belongs to this class, so supply appropriate values to be
+   passed to the parent class loader (and its parent, etc.). */
+   if ( !vtab ) {
+      size = sizeof( AstStc );
+      vtab = &class_vtab;
+      name = "Stc";
+
+/* If required, initialise the virtual function table for this class. */
+      if ( !class_init ) {
+         astInitStcVtab( vtab, name );
+         class_init = 1;
+      }
+   }
+
+/* Invoke the parent class loader to load data for all the ancestral
+   classes of the current one, returning a pointer to the resulting
+   partly-built Stc. */
+   new = astLoadRegion( mem, size, (AstRegionVtab *) vtab, name,
+                        channel );
+
+   if ( astOK ) {
+
+/* Read input data. */
+/* ================ */
+/* Request the input Channel to read all the input data appropriate to
+   this class into the internal "values list". */
+      astReadClassData( channel, "Stc" );
+
+/* Now read each individual data item from this list and use it to
+   initialise the appropriate instance variable(s) for this class. */
+
+/* In the case of attributes, we first read the "raw" input value,
+   supplying the "unset" value as the default. If a "set" value is
+   obtained, we then use the appropriate (private) Set... member
+   function to validate and set the value properly. */
+
+/* Encapsulated Region. */
+/* -------------------- */
+      new->region = astReadObject( channel, "region", NULL );
+
+/* Get a pointer to the base Frame in the FrameSet encapsulated by the
+   parent Region structure. */
+      f1 = astGetFrame( ((AstRegion *) new)->frameset, AST__BASE );
+
+/* If the encapsulated Region has a dummy FrameSet rather than the correct
+   FrameSet, the correct FrameSet will have copies of the base Frame of the
+   new Stc as both its current and base Frames, connected by a UnitMap (this
+   is equivalent to a FrameSet containing a single Frame). However if the new
+   Stc being loaded has itself got a dummy FrameSet, then we do not do this
+   since we do not yet know what the correct FrameSet is. In this case we
+   wait until the parent Region invokes the astSetRegFS method on the new
+   Stc. */
+      if( !astRegDummyFS( new ) ) {
+         creg = new->region;
+         if( astRegDummyFS( creg ) ) astSetRegFS( creg, f1 );
+      }
+
+/* AstroCoords info */
+/* ---------------- */
+/* The number of AstroCoords described in the new Stc. */
+      new->ncoord = astReadInt( channel, "ncoord", 0 );
+      if( new->ncoord < 0 ) new->ncoord = 0;
+
+/* Read back each KeyMap describing these AstroCoords. */
+      new->coord = astMalloc( sizeof( AstKeyMap *) * (size_t) new->ncoord );
+      for( ico = 1; ico <= new->ncoord; ico++ ) {
+         (void) sprintf( key, "coord%d", ico );
+         new->coord[ ico - 1 ] = astReadObject( channel, key, NULL );
+
+/* Ensure the Regions within the KeyMap do not have dummy FrameSets. */
+         if( new->coord[ ico - 1 ] && !astRegDummyFS( new ) ) {
+            for( ikey = 0; ikey < NREG; ikey++ ) {
+               if( astMapGet0A( new->coord[ ico - 1 ], regkey[ ikey ], &obj ) ){
+                  creg = (AstRegion *) obj;
+                  if( astRegDummyFS( creg ) ) {
+                     astSetRegFS( creg, f1 );
+                     astMapPut0A( new->coord[ ico - 1 ], regkey[ ikey ], creg,
+                                  regcom[ ikey ] );
+                  }
+                  creg = astAnnul( creg );
+               }
+            }
+         }
+      }
+
+/* Free resources */
+      f1 = astAnnul( f1 );
+
+/* If an error occurred, clean up by deleting the new Stc. */
+      if ( !astOK ) new = astDelete( new );
+   }
+
+/* Return the new Stc pointer. */
+   return new;
+
+/* Undefine macros local to this function. */
+#undef KEY_LEN
+}
+
+/* Virtual function interfaces. */
+/* ============================ */
+/* These provide the external interface to the virtual functions defined by
+   this class. Each simply checks the global error status and then locates and
+   executes the appropriate member function, using the function pointer stored
+   in the object's virtual function table (this pointer is located using the
+   astMEMBER macro defined in "object.h").
+
+   Note that the member function may not be the one defined here, as it may
+   have been over-ridden by a derived class. However, it should still have the
+   same interface. */
+
+const char *astGetRegionClass_( AstStc *this, int *status ){
+   if ( !astOK ) return NULL;
+   return (**astMEMBER(this,Stc,GetRegionClass))( this, status );
+}
+
+AstRegion *astGetStcRegion_( AstStc *this, int *status ){
+   if ( !astOK ) return NULL;
+   return (**astMEMBER(this,Stc,GetStcRegion))( this, status );
+}
+
+AstKeyMap *astGetStcCoord_( AstStc *this, int icoord, int *status ){
+   if ( !astOK ) return NULL;
+   return (**astMEMBER(this,Stc,GetStcCoord))( this, icoord, status );
+}
+
+int astGetStcNCoord_( AstStc *this, int *status ){
+   if ( !astOK ) return 0;
+   return (**astMEMBER(this,Stc,GetStcNCoord))( this, status );
+}
+
+
+
+
+
+
+
+
+
+
+
+
+