diff options
Diffstat (limited to 'ast/shiftmap.c')
| -rw-r--r-- | ast/shiftmap.c | 1617 |
1 files changed, 1617 insertions, 0 deletions
diff --git a/ast/shiftmap.c b/ast/shiftmap.c new file mode 100644 index 0000000..eed6e1d --- /dev/null +++ b/ast/shiftmap.c @@ -0,0 +1,1617 @@ +/* +*class++ +* Name: +* ShiftMap + +* Purpose: +* Add a constant value to each coordinate. + +* Constructor Function: +c astShiftMap +f AST_SHIFTMAP + +* Description: +* A ShiftMap is a linear Mapping which shifts each axis by a +* specified constant value. + +* Inheritance: +* The ShiftMap class inherits from the Mapping class. + +* Attributes: +* The ShiftMap class does not define any new attributes beyond those +* which are applicable to all Mappings. + +* Functions: +c The ShiftMap class does not define any new functions beyond those +f The ShiftMap class does not define any new routines beyond those +* which are applicable to all Mappings. + +* Copyright: +* Copyright (C) 1997-2006 Council for the Central Laboratory of the +* Research Councils + +* 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 Berry (Starlink) + +* History: +* 15-AUG-2003 (DSB): +* Original version. +* 14-FEB-2006 (DSB): +* Override astGetObjSize. +* 10-MAY-2006 (DSB): +* Override astEqual. +*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 ShiftMap + +/* Include files. */ +/* ============== */ +/* Interface definitions. */ +/* ---------------------- */ + +#include "globals.h" /* Thread-safe global data access */ +#include "error.h" /* Error reporting facilities */ +#include "memory.h" /* Memory management facilities */ +#include "object.h" /* Base Object class */ +#include "pointset.h" /* Sets of points/coordinates */ +#include "matrixmap.h" /* Linear mappings */ +#include "unitmap.h" /* Unit mappings */ +#include "zoommap.h" /* Zoom mappings */ +#include "permmap.h" /* Axis permutations */ +#include "mapping.h" /* Coordinate mappings (parent class) */ +#include "channel.h" /* I/O channels */ +#include "winmap.h" /* Window mappings */ +#include "shiftmap.h" /* Interface definition for this class */ + +/* Error code definitions. */ +/* ----------------------- */ +#include "ast_err.h" /* AST error codes */ + +/* C header files. */ +/* --------------- */ +#include <float.h> +#include <math.h> +#include <stdarg.h> +#include <stddef.h> +#include <stdio.h> +#include <string.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 int (* parent_getobjsize)( AstObject *, int * ); +static AstPointSet *(* parent_transform)( AstMapping *, AstPointSet *, int, AstPointSet *, int * ); + + +#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(ShiftMap) + +/* Define macros for accessing each item of thread specific global data. */ +#define class_init astGLOBAL(ShiftMap,Class_Init) +#define class_vtab astGLOBAL(ShiftMap,Class_Vtab) + + +#include <pthread.h> + + +#else + + +/* Define the class virtual function table and its initialisation flag + as static variables. */ +static AstShiftMapVtab class_vtab; /* Virtual function table */ +static int class_init = 0; /* Virtual function table initialised? */ + +#endif + +/* External Interface Function Prototypes. */ +/* ======================================= */ +/* The following functions have public prototypes only (i.e. no + protected prototypes), so we must provide local prototypes for use + within this module. */ +AstShiftMap *astShiftMapId_( int, const double [], const char *, ... ); + +/* Prototypes for Private Member Functions. */ +/* ======================================== */ + +static AstPointSet *Transform( AstMapping *, AstPointSet *, int, AstPointSet *, int * ); +static int GetObjSize( AstObject *, int * ); +static double Rate( AstMapping *, double *, int, int, int * ); +static int MapMerge( AstMapping *, int, int, int *, AstMapping ***, int **, int * ); +static void Copy( const AstObject *, AstObject *, int * ); +static void Delete( AstObject *, int * ); +static void Dump( AstObject *, AstChannel *, int * ); +static int Equal( AstObject *, AstObject *, int * ); +static int GetIsLinear( AstMapping *, int * ); +static int *MapSplit( AstMapping *, int, const int *, AstMapping **, int * ); + +/* Member functions. */ +/* ================= */ + +static int Equal( AstObject *this_object, AstObject *that_object, int *status ) { +/* +* Name: +* Equal + +* Purpose: +* Test if two ShiftMaps are equivalent. + +* Type: +* Private function. + +* Synopsis: +* #include "shiftmap.h" +* int Equal( AstObject *this, AstObject *that, int *status ) + +* Class Membership: +* ShiftMap member function (over-rides the astEqual protected +* method inherited from the astMapping class). + +* Description: +* This function returns a boolean result (0 or 1) to indicate whether +* two ShiftMaps are equivalent. + +* Parameters: +* this +* Pointer to the first Object (a ShiftMap). +* that +* Pointer to the second Object. +* status +* Pointer to the inherited status variable. + +* Returned Value: +* One if the ShiftMaps are equivalent, zero otherwise. + +* 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: */ + AstShiftMap *that; + AstShiftMap *this; + int i; + int nin; + int nout; + int result; + +/* Initialise. */ + result = 0; + +/* Check the global error status. */ + if ( !astOK ) return result; + +/* Obtain pointers to the two ShiftMap structures. */ + this = (AstShiftMap *) this_object; + that = (AstShiftMap *) that_object; + +/* Check the second object is a ShiftMap. We know the first is a + ShiftMap since we have arrived at this implementation of the virtual + function. */ + if( astIsAShiftMap( that ) ) { + +/* Get the number of inputs and outputs and check they are the same for both. */ + nin = astGetNin( this ); + nout = astGetNout( this ); + if( astGetNin( that ) == nin && astGetNout( that ) == nout ) { + +/* If the Invert flags for the two ShiftMaps differ, it may still be possible + for them to be equivalent. First compare the ShiftMaps if their Invert + flags are the same. In this case all the attributes of the two ShiftMaps + must be identical. */ + if( astGetInvert( this ) == astGetInvert( that ) ) { + result = 1; + for( i = 0; i < nin; i++ ) { + if( !astEQUAL( this->shift[ i ], that->shift[ i ] ) ) { + result = 0; + break; + } + } + +/* If the Invert flags for the two ShiftMaps differ, the attributes of the two + ShiftMaps must be inversely related to each other. */ + } else { + + result = 1; + for( i = 0; i < nin; i++ ) { + if( !astEQUAL( this->shift[ i ], -(that->shift[ i ] ) ) ) { + result = 0; + break; + } + } + + } + } + } + +/* If an error occurred, clear the result value. */ + if ( !astOK ) result = 0; + +/* Return the result, */ + return result; +} + +static int GetIsLinear( AstMapping *this_mapping, int *status ){ +/* +* Name: +* GetIsLinear + +* Purpose: +* Return the value of the IsLinear attribute for a ShiftMap. + +* Type: +* Private function. + +* Synopsis: +* #include "mapping.h" +* void GetIsLinear( AstMapping *this, int *status ) + +* Class Membership: +* ShiftMap member function (over-rides the protected astGetIsLinear +* method inherited from the Mapping class). + +* Description: +* This function returns the value of the IsLinear attribute for a +* Frame, which is always one. + +* Parameters: +* this +* Pointer to the ShiftMap. +* status +* Pointer to the inherited status variable. +*/ + return 1; +} + +static int GetObjSize( AstObject *this_object, int *status ) { +/* +* Name: +* GetObjSize + +* Purpose: +* Return the in-memory size of an Object. + +* Type: +* Private function. + +* Synopsis: +* #include "shiftmap.h" +* int GetObjSize( AstObject *this, int *status ) + +* Class Membership: +* ShiftMap member function (over-rides the astGetObjSize protected +* method inherited from the parent class). + +* Description: +* This function returns the in-memory size of the supplied ShiftMap, +* in bytes. + +* Parameters: +* this +* Pointer to the ShiftMap. +* 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: */ + AstShiftMap *this; /* Pointer to ShiftMap structure */ + int result; /* Result value to return */ + +/* Initialise. */ + result = 0; + +/* Check the global error status. */ + if ( !astOK ) return result; + +/* Obtain a pointers to the ShiftMap structure. */ + this = (AstShiftMap *) 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 += astTSizeOf( this->shift ); + +/* If an error occurred, clear the result value. */ + if ( !astOK ) result = 0; + +/* Return the result, */ + return result; +} + +void astInitShiftMapVtab_( AstShiftMapVtab *vtab, const char *name, int *status ) { +/* +*+ +* Name: +* astInitShiftMapVtab + +* Purpose: +* Initialise a virtual function table for a ShiftMap. + +* Type: +* Protected function. + +* Synopsis: +* #include "shiftmap.h" +* void astInitShiftMapVtab( AstShiftMapVtab *vtab, const char *name ) + +* Class Membership: +* ShiftMap vtab initialiser. + +* Description: +* This function initialises the component of a virtual function +* table which is used by the ShiftMap 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 */ + +/* 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. */ + astInitMappingVtab( (AstMappingVtab *) vtab, name ); + +/* Store a unique "magic" value in the virtual function table. This + will be used (by astIsAShiftMap) 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 = &(((AstMappingVtab *) vtab)->id); + +/* Initialise member function pointers. */ +/* ------------------------------------ */ +/* Store pointers to the member functions (implemented here) that provide + virtual methods for this class. */ + +/* 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; + parent_getobjsize = object->GetObjSize; + object->GetObjSize = GetObjSize; + + parent_transform = mapping->Transform; + mapping->Transform = Transform; + +/* Store replacement pointers for methods which will be over-ridden by + new member functions implemented here. */ + object->Equal = Equal; + mapping->MapMerge = MapMerge; + mapping->Rate = Rate; + mapping->MapSplit = MapSplit; + mapping->GetIsLinear = GetIsLinear; + +/* Declare the class dump, copy and delete functions.*/ + astSetDump( vtab, Dump, "ShiftMap", "Shift each coordinate axis" ); + astSetCopy( (AstObjectVtab *) vtab, Copy ); + astSetDelete( (AstObjectVtab *) vtab, Delete ); + +/* 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 int MapMerge( AstMapping *this, int where, int series, int *nmap, + AstMapping ***map_list, int **invert_list, int *status ) { +/* +* Name: +* MapMerge + +* Purpose: +* Simplify a sequence of Mappings containing a ShiftMap. + +* Type: +* Private function. + +* Synopsis: +* #include "mapping.h" +* int MapMerge( AstMapping *this, int where, int series, int *nmap, +* AstMapping ***map_list, int **invert_list, int *status ) + +* Class Membership: +* ShiftMap method (over-rides the protected astMapMerge method +* inherited from the Mapping class). + +* Description: +* This function attempts to simplify a sequence of Mappings by +* merging a nominated ShiftMap in the sequence with its neighbours, +* so as to shorten the sequence if possible. +* +* In many cases, simplification will not be possible and the +* function will return -1 to indicate this, without further +* action. +* +* In most cases of interest, however, this function will either +* attempt to replace the nominated ShiftMap with a Mapping which it +* considers simpler, or to merge it with the Mappings which +* immediately precede it or follow it in the sequence (both will +* normally be considered). This is sufficient to ensure the +* eventual simplification of most Mapping sequences by repeated +* application of this function. +* +* In some cases, the function may attempt more elaborate +* simplification, involving any number of other Mappings in the +* sequence. It is not restricted in the type or scope of +* simplification it may perform, but will normally only attempt +* elaborate simplification in cases where a more straightforward +* approach is not adequate. + +* Parameters: +* this +* Pointer to the nominated ShiftMap which is to be merged with +* its neighbours. This should be a cloned copy of the ShiftMap +* pointer contained in the array element "(*map_list)[where]" +* (see below). This pointer will not be annulled, and the +* ShiftMap it identifies will not be modified by this function. +* where +* Index in the "*map_list" array (below) at which the pointer +* to the nominated ShiftMap resides. +* series +* A non-zero value indicates that the sequence of Mappings to +* be simplified will be applied in series (i.e. one after the +* other), whereas a zero value indicates that they will be +* applied in parallel (i.e. on successive sub-sets of the +* input/output coordinates). +* nmap +* Address of an int which counts the number of Mappings in the +* sequence. On entry this should be set to the initial number +* of Mappings. On exit it will be updated to record the number +* of Mappings remaining after simplification. +* map_list +* Address of a pointer to a dynamically allocated array of +* Mapping pointers (produced, for example, by the astMapList +* method) which identifies the sequence of Mappings. On entry, +* the initial sequence of Mappings to be simplified should be +* supplied. +* +* On exit, the contents of this array will be modified to +* reflect any simplification carried out. Any form of +* simplification may be performed. This may involve any of: (a) +* removing Mappings by annulling any of the pointers supplied, +* (b) replacing them with pointers to new Mappings, (c) +* inserting additional Mappings and (d) changing their order. +* +* The intention is to reduce the number of Mappings in the +* sequence, if possible, and any reduction will be reflected in +* the value of "*nmap" returned. However, simplifications which +* do not reduce the length of the sequence (but improve its +* execution time, for example) may also be performed, and the +* sequence might conceivably increase in length (but normally +* only in order to split up a Mapping into pieces that can be +* more easily merged with their neighbours on subsequent +* invocations of this function). +* +* If Mappings are removed from the sequence, any gaps that +* remain will be closed up, by moving subsequent Mapping +* pointers along in the array, so that vacated elements occur +* at the end. If the sequence increases in length, the array +* will be extended (and its pointer updated) if necessary to +* accommodate any new elements. +* +* Note that any (or all) of the Mapping pointers supplied in +* this array may be annulled by this function, but the Mappings +* to which they refer are not modified in any way (although +* they may, of course, be deleted if the annulled pointer is +* the final one). +* invert_list +* Address of a pointer to a dynamically allocated array which, +* on entry, should contain values to be assigned to the Invert +* attributes of the Mappings identified in the "*map_list" +* array before they are applied (this array might have been +* produced, for example, by the astMapList method). These +* values will be used by this function instead of the actual +* Invert attributes of the Mappings supplied, which are +* ignored. +* +* On exit, the contents of this array will be updated to +* correspond with the possibly modified contents of the +* "*map_list" array. If the Mapping sequence increases in +* length, the "*invert_list" array will be extended (and its +* pointer updated) if necessary to accommodate any new +* elements. +* status +* Pointer to the inherited status variable. + +* Returned Value: +* If simplification was possible, the function returns the index +* in the "map_list" array of the first element which was +* modified. Otherwise, it returns -1 (and makes no changes to the +* arrays supplied). + +* Notes: +* - A value of -1 will be returned if this function is invoked +* with the global error status set, or if it should fail for any +* reason. +*/ + +/* Local Variables: */ + AstWinMap *w1; /* Pointer to replacement Mapping */ + AstShiftMap *sm; /* Pointer to this ShiftMap */ + double *aa; /* Pointer to shift terms for new WinMap */ + double *bb; /* Pointer to scale terms for new WinMap */ + int i; /* Axis count */ + int nin; /* Number of axes */ + int result; /* Returned value */ + +/* Initialise. */ + result = -1; + +/* Check the global error status. */ + if ( !astOK ) return result; + +/* A ShiftMap is equivalent to a WinMap with unit scaling. The policy on + simplifying a ShiftMap is to convert it to the equivalent WinMap and let + the WinMap class do the simplifying. Create the returned WinMap, initially + with undefined corners. */ + nin = astGetNin( this ); + w1 = astWinMap( nin, NULL, NULL, NULL, NULL, "", status ); + +/* If succesful, store the scale and shift terms in the WinMap. The scale + terms are unity. */ + if( astOK ){ + sm = (AstShiftMap *) this; + + bb = w1->b; + aa = w1->a; + for( i = 0; i < nin; i++ ) { + *(bb++) = 1.0; + *(aa++) = ( *invert_list )[ where ] ? -(sm->shift)[ i ] : (sm->shift)[ i ]; + } + +/* Replace the supplied ShiftMap with the new WinMap and reset the invert + flag. */ + (void) astAnnul( ( *map_list )[ where ] ); + ( *map_list )[ where ] = (AstMapping *) w1; + ( *invert_list )[ where ] = 0; + +/* Return the index of the first modified element. */ + result = where; + } + +/* Return the result. */ + return result; +} + +static int *MapSplit( AstMapping *this_map, int nin, const int *in, AstMapping **map, int *status ){ +/* +* Name: +* MapSplit + +* Purpose: +* Create a Mapping representing a subset of the inputs of an existing +* ShiftMap. + +* Type: +* Private function. + +* Synopsis: +* #include "shiftmap.h" +* int *MapSplit( AstMapping *this, int nin, const int *in, AstMapping **map, int *status ) + +* Class Membership: +* ShiftMap method (over-rides the protected astMapSplit method +* inherited from the Mapping class). + +* Description: +* This function creates a new Mapping by picking specified inputs from +* an existing ShiftMap. This is only possible if the specified inputs +* correspond to some subset of the ShiftMap outputs. That is, there +* must exist a subset of the ShiftMap outputs for which each output +* depends only on the selected ShiftMap inputs, and not on any of the +* inputs which have not been selected. If this condition is not met +* by the supplied ShiftMap, then a NULL Mapping is returned. + +* Parameters: +* this +* Pointer to the ShiftMap to be split (the ShiftMap is not actually +* modified by this function). +* nin +* The number of inputs to pick from "this". +* in +* Pointer to an array of indices (zero based) for the inputs which +* are to be picked. This array should have "nin" elements. If "Nin" +* is the number of inputs of the supplied ShiftMap, then each element +* should have a value in the range zero to Nin-1. +* map +* Address of a location at which to return a pointer to the new +* Mapping. This Mapping will have "nin" inputs (the number of +* outputs may be different to "nin"). A NULL pointer will be +* returned if the supplied ShiftMap has no subset of outputs which +* depend only on the selected inputs. +* status +* Pointer to the inherited status variable. + +* Returned Value: +* A pointer to a dynamically allocated array of ints. The number of +* elements in this array will equal the number of outputs for the +* returned Mapping. Each element will hold the index of the +* corresponding output in the supplied ShiftMap. The array should be +* freed using astFree when no longer needed. A NULL pointer will +* be returned if no output Mapping can be created. + +* Notes: +* - If this function is invoked with the global error status set, +* or if it should fail for any reason, then NULL values will be +* returned as the function value and for the "map" pointer. +*/ + +/* Local Variables: */ + AstShiftMap *newsm; /* Pointer to returned ShiftMap */ + AstShiftMap *this; /* Pointer to ShiftMap structure */ + int *result; /* Pointer to returned array */ + int i; /* Loop count */ + int iin; /* Mapping input index */ + int mnin; /* No. of Mapping inputs */ + int ok; /* Are input indices OK? */ + +/* Initialise */ + result = NULL; + *map = NULL; + +/* Check the global error status. */ + if ( !astOK ) return result; + +/* Get a pointer to the ShiftMap structure. */ + this = (AstShiftMap *) this_map; + +/* Allocate memory for the returned array and create a ShiftMap with the + required number of axes and initially unsorted shifts. */ + result = astMalloc( sizeof( int )*(size_t) nin ); + newsm = astShiftMap( nin, this->shift, "", status ); + *map = (AstMapping *) newsm; + +/* Check pointers can be used safely. */ + if( astOK ) { + +/* Store the required shifts in the new ShiftMap. At the same time check + that each axis is valid. */ + mnin = astGetNin( this ); + ok = 1; + for( i = 0; i < nin; i++ ) { + iin = in[ i ]; + if( iin >= 0 && iin < mnin ) { + (newsm->shift)[ i ] = (this->shift)[ iin ]; + result[ i ] = iin; + } else { + ok = 0; + break; + } + } + +/* If the "in" array contained any invalid values, free the returned + resources. */ + if( !ok ) { + result = astFree( result ); + *map = astAnnul( *map ); + +/* If the indices are good, invert the returned ShiftMap if the supplied + ShiftMap is inverted. */ + } else { + if( astGetInvert( this ) ) astInvert( *map ); + } + } + +/* Free returned resources if an error has occurred. */ + if( !astOK ) { + result = astFree( result ); + *map = astAnnul( *map ); + } + +/* Return the list of output indices. */ + return result; +} + +static double Rate( AstMapping *this, double *at, int ax1, int ax2, int *status ){ +/* +* Name: +* Rate + +* Purpose: +* Calculate the rate of change of a Mapping output. + +* Type: +* Private function. + +* Synopsis: +* #include "shiftmap.h" +* result = Rate( AstMapping *this, double *at, int ax1, int ax2, int *status ) + +* Class Membership: +* ShiftMap member function (overrides the astRate method inherited +* from the Mapping class ). + +* Description: +* This function returns the rate of change of a specified output of +* the supplied Mapping with respect to a specified input, at a +* specified input position. + +* Parameters: +* this +* Pointer to the Mapping to be applied. +* at +* The address of an array holding the axis values at the position +* at which the rate of change is to be evaluated. The number of +* elements in this array should equal the number of inputs to the +* Mapping. +* ax1 +* The index of the Mapping output for which the rate of change is to +* be found (output numbering starts at 0 for the first output). +* ax2 +* The index of the Mapping input which is to be varied in order to +* find the rate of change (input numbering starts at 0 for the first +* input). +* status +* Pointer to the inherited status variable. + +* Returned Value: +* The rate of change of Mapping output "ax1" with respect to input +* "ax2", evaluated at "at", or AST__BAD if the value cannot be +* calculated. + +*/ + + return ( ax1 == ax2 ) ? 1.0 : 0.0; +} + +static AstPointSet *Transform( AstMapping *this, AstPointSet *in, + int forward, AstPointSet *out, int *status ) { +/* +* Name: +* Transform + +* Purpose: +* Apply a ShiftMap to transform a set of points. + +* Type: +* Private function. + +* Synopsis: +* #include "shiftmap.h" +* AstPointSet *Transform( AstMapping *this, AstPointSet *in, +* int forward, AstPointSet *out, int *status ) + +* Class Membership: +* ShiftMap member function (over-rides the astTransform protected +* method inherited from the Mapping class). + +* Description: +* This function takes a ShiftMap and a set of points encapsulated in a +* PointSet and transforms the points so as to map them into the +* required window. + +* Parameters: +* this +* Pointer to the ShiftMap. +* in +* Pointer to the PointSet holding the input coordinate data. +* 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 ShiftMap 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 *result; /* Pointer to output PointSet */ + AstShiftMap *map; /* Pointer to ShiftMap to be applied */ + const char *class; /* Object class */ + double **ptr_in; /* Pointer to input coordinate data */ + double **ptr_out; /* Pointer to output coordinate data */ + double *axin; /* Pointer to next input axis value */ + double *axout; /* Pointer to next output axis value */ + double a; /* Shift for current axis */ + int coord; /* Loop counter for coordinates */ + int ncoord; /* Number of coordinates per point */ + int npoint; /* Number of points */ + int point; /* Loop counter for points */ + +/* Check the global error status. */ + if ( !astOK ) return NULL; + +/* Obtain a pointer to the ShiftMap. */ + map = (AstShiftMap *) this; + +/* Apply the parent mapping using the stored pointer to the Transform member + function inherited from the parent Mapping class. This function validates + all arguments and generates an output PointSet if necessary, but does not + actually transform any coordinate values. */ + result = (*parent_transform)( this, in, forward, out, status ); + +/* We will now extend the parent astTransform method by performing the + calculations needed to generate the output coordinate values. */ + +/* Determine the numbers of points and coordinates per point from the input + PointSet and obtain pointers for accessing the input and output coordinate + values. */ + ncoord = astGetNcoord( in ); + npoint = astGetNpoint( in ); + ptr_in = astGetPoints( in ); + ptr_out = astGetPoints( result ); + +/* Determine whether to apply the forward or inverse mapping, according to the + direction specified and whether the mapping has been inverted. */ + if ( astGetInvert( map ) ) forward = !forward; + +/* Report an error if the ShiftMap does not contain any shifts. */ + if( !map->shift && astOK ){ + class = astGetClass( this ); + astError( AST__BADSM, "astTransform(%s): The supplied %s does not " + "contain any shift information.", status, class, class ); + } + +/* Perform coordinate arithmetic. */ +/* ------------------------------ */ + if( astOK ){ + +/* Apply the mapping to each axis. */ + for( coord = 0; coord < ncoord; coord++ ){ + +/* Store pointers to the first input and output values on this axis. */ + axin = ptr_in[ coord ]; + axout = ptr_out[ coord ]; + +/* Get the value to add to each axis value. */ + a = (map->shift)[ coord ]; + +/* If the shift is bad store bad output values. */ + if( a == AST__BAD ){ + for( point = 0; point < npoint; point++ ) *(axout++) = AST__BAD; + +/* Otherwise, shift this axis, taking account of whether the mapping is + inverted or not. */ + } else { + if( !forward ) a = -a; + + for( point = 0; point < npoint; point++ ){ + if( *axin != AST__BAD ){ + *(axout++) = (*axin) + a; + } else { + *(axout++) = AST__BAD; + } + axin++; + } + } + } + } + +/* Return a pointer to the output PointSet. */ + return result; +} + +/* Functions which access class attributes. */ +/* ---------------------------------------- */ +/* Implement member functions to access the attributes associated with + this class using the macros defined for this purpose in the + "object.h" file. For a description of each attribute, see the class + interface (in the associated .h file). */ + +/* Copy constructor. */ +/* ----------------- */ +static void Copy( const AstObject *objin, AstObject *objout, int *status ) { +/* +* Name: +* Copy + +* Purpose: +* Copy constructor for ShiftMap objects. + +* Type: +* Private function. + +* Synopsis: +* void Copy( const AstObject *objin, AstObject *objout, int *status ) + +* Description: +* This function implements the copy constructor for ShiftMap objects. + +* Parameters: +* objin +* Pointer to the ShiftMap to be copied. +* objout +* Pointer to the ShiftMap being constructed. +* status +* Pointer to the inherited status variable. + +*/ + +/* Local Variables: */ + AstShiftMap *out; /* Pointer to output ShiftMap */ + AstShiftMap *in; /* Pointer to input ShiftMap */ + int ncoord; /* No. of axes for the mapping */ + +/* Check the global error status. */ + if ( !astOK ) return; + +/* Obtain a pointer to the input and output ShiftMaps. */ + in= (AstShiftMap *) objin; + out = (AstShiftMap *) objout; + +/* Get the number of coordinates mapped by the ShiftMap. */ + ncoord = astGetNin( in ); + +/* Allocate memory holding copies of the shifts defining the mapping. */ + out->shift = (double *) astStore( NULL, (void *) in->shift, + sizeof(double)*(size_t)ncoord ); + +/* If an error occurred, free any allocated memory. */ + if ( !astOK ) { + out->shift = (double *) astFree( (void *) out->shift ); + } + +} + +/* Destructor. */ +/* ----------- */ +static void Delete( AstObject *obj, int *status ) { +/* +* Name: +* Delete + +* Purpose: +* Destructor for ShiftMap objects. + +* Type: +* Private function. + +* Synopsis: +* void Delete( AstObject *obj, int *status ) + +* Description: +* This function implements the destructor for ShiftMap objects. + +* Parameters: +* obj +* Pointer to the ShiftMap to be deleted. +* status +* Pointer to the inherited status variable. + +* Notes: +* - This destructor does nothing and exists only to maintain a +* one-to-one correspondence between destructors and copy +* constructors. +*/ + +/* Local Variables: */ + AstShiftMap *this; /* Pointer to ShiftMap */ + +/* Obtain a pointer to the ShiftMap structure. */ + this = (AstShiftMap *) obj; + +/* Free the memory holding the shifts. */ + this->shift = (double *) astFree( (void *) this->shift ); + +} + +/* Dump function. */ +/* -------------- */ +static void Dump( AstObject *this_object, AstChannel *channel, int *status ) { +/* +* Name: +* Dump + +* Purpose: +* Dump function for ShiftMap 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 ShiftMap class to an output Channel. + +* Parameters: +* this +* Pointer to the ShiftMap 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 50 /* Maximum length of a comment string */ +#define KEY_LEN 50 /* Maximum length of a keyword */ + +/* Local Variables: */ + AstShiftMap *this; /* Pointer to the ShiftMap structure */ + char buff[ KEY_LEN + 1 ]; /* Buffer for keyword string */ + char comment[ COMMENT_LEN + 1 ]; /* Buffer for comment string */ + int axis; /* Axis index */ + int ncoord; /* No. of axes for mapping */ + +/* Check the global error status. */ + if ( !astOK ) return; + +/* Obtain a pointer to the ShiftMap structure. */ + this = (AstShiftMap *) this_object; + +/* Get the number of coordinates to be mapped. */ + ncoord = astGetNin( this ); + +/* Write out values representing the instance variables for the + ShiftMap class. Accompany these with appropriate comment strings, + possibly depending on the values being written.*/ + +/* The shifts. */ + for( axis = 0; axis < ncoord; axis++ ){ + (void) sprintf( buff, "Sft%d", axis + 1 ); + (void) sprintf( comment, "Shift for axis %d", axis + 1 ); + astWriteDouble( channel, buff, (this->shift)[ axis ] != 0.0, 0, + (this->shift)[ axis ], comment ); + } + +/* Undefine macros local to this function. */ +#undef COMMENT_LEN +#undef KEY_LEN +} + +/* Standard class functions. */ +/* ========================= */ +/* Implement the astIsAShiftMap and astCheckShiftMap functions using the macros + defined for this purpose in the "object.h" header file. */ +astMAKE_ISA(ShiftMap,Mapping) +astMAKE_CHECK(ShiftMap) + +AstShiftMap *astShiftMap_( int ncoord, const double shift[], const char *options, int *status, ...) { +/* +*++ +* Name: +c astShiftMap +f AST_SHIFTMAP + +* Purpose: +* Create a ShiftMap. + +* Type: +* Public function. + +* Synopsis: +c #include "shiftmap.h" +c AstShiftMap *astShiftMap( int ncoord, const double shift[], +c const char *options, ... ) +f RESULT = AST_SHIFTMAP( NCOORD, SHIFT, OPTIONS, STATUS ) + +* Class Membership: +* ShiftMap constructor. + +* Description: +* This function creates a new ShiftMap and optionally initialises its +* attributes. +* +* A ShiftMap is a linear Mapping which shifts each axis by a +* specified constant value. + +* Parameters: +c ncoord +f NCOORD = INTEGER (Given) +* The number of coordinate values for each point to be +* transformed (i.e. the number of dimensions of the space in +* which the points will reside). The same number is applicable +* to both input and output points. +c shift +f SHIFT( NCOORD ) = DOUBLE PRECISION (Given) +* An array containing the values to be added on to the input +* coordinates in order to create the output coordinates. A separate +* value should be supplied for each coordinate. +c options +f OPTIONS = CHARACTER * ( * ) (Given) +c Pointer to a null-terminated string containing an optional +c comma-separated list of attribute assignments to be used for +c initialising the new ShiftMap. The syntax used is identical to +c that for the astSet function and may include "printf" format +c specifiers identified by "%" symbols in the normal way. +f A character string containing an optional comma-separated +f list of attribute assignments to be used for initialising the +f new ShiftMap. The syntax used is identical to that for the +f AST_SET routine. +c ... +c If the "options" string contains "%" format specifiers, then +c an optional list of additional arguments may follow it in +c order to supply values to be substituted for these +c specifiers. The rules for supplying these are identical to +c those for the astSet function (and for the C "printf" +c function). +f STATUS = INTEGER (Given and Returned) +f The global status. + +* Returned Value: +c astShiftMap() +f AST_SHIFTMAP = INTEGER +* A pointer to the new ShiftMap. + +* 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. + +* Status Handling: +* The protected interface to this function includes an extra +* parameter at the end of the parameter list descirbed above. This +* parameter is a pointer to the integer inherited status +* variable: "int *status". + +*-- +*/ + +/* Local Variables: */ + astDECLARE_GLOBALS /* Pointer to thread-specific global data */ + AstShiftMap *new; /* Pointer to new ShiftMap */ + va_list args; /* Variable argument list */ + +/* Get a pointer to the thread specific global data structure. */ + astGET_GLOBALS(NULL); + +/* Check the global status. */ + if ( !astOK ) return NULL; + +/* Initialise the ShiftMap, allocating memory and initialising the + virtual function table as well if necessary. */ + new = astInitShiftMap( NULL, sizeof( AstShiftMap ), !class_init, &class_vtab, + "ShiftMap", ncoord, shift ); + +/* If successful, note that the virtual function table has been + initialised. */ + if ( astOK ) { + class_init = 1; + +/* Obtain the variable argument list and pass it along with the options string + to the astVSet method to initialise the new ShiftMap's attributes. */ + va_start( args, status ); + astVSet( new, options, NULL, args ); + va_end( args ); + +/* If an error occurred, clean up by deleting the new object. */ + if ( !astOK ) new = astDelete( new ); + } + +/* Return a pointer to the new ShiftMap. */ + return new; +} + +AstShiftMap *astShiftMapId_( int ncoord, const double shift[], + const char *options, ... ) { +/* +* Name: +* astShiftMapId_ + +* Purpose: +* Create a ShiftMap. + +* Type: +* Private function. + +* Synopsis: +* #include "shiftmap.h" +* AstShiftMap *astShiftMapId_( int ncoord, const double shift[], +* const char *options, ... ) + +* Class Membership: +* ShiftMap constructor. + +* Description: +* This function implements the external (public) interface to the +* astShiftMap constructor function. It returns an ID value (instead +* of a true C pointer) to external users, and must be provided +* because astShiftMap_ has a variable argument list which cannot be +* encapsulated in a macro (where this conversion would otherwise +* occur). +* +* The variable argument list also prevents this function from +* invoking astShiftMap_ directly, so it must be a re-implementation +* of it in all respects, except for the final conversion of the +* result to an ID value. + +* Parameters: +* As for astShiftMap_. + +* Returned Value: +* The ID value associated with the new ShiftMap. +*/ + +/* Local Variables: */ + astDECLARE_GLOBALS /* Pointer to thread-specific global data */ + AstShiftMap *new; /* Pointer to new ShiftMap */ + va_list args; /* Variable argument list */ + + int *status; /* Pointer to inherited status value */ + +/* Get a pointer to the inherited status value. */ + status = astGetStatusPtr; + +/* Get a pointer to the thread specific global data structure. */ + astGET_GLOBALS(NULL); + +/* Check the global status. */ + if ( !astOK ) return NULL; + +/* Initialise the ShiftMap, allocating memory and initialising the + virtual function table as well if necessary. */ + new = astInitShiftMap( NULL, sizeof( AstShiftMap ), !class_init, &class_vtab, + "ShiftMap", ncoord, shift ); + +/* If successful, note that the virtual function table has been + initialised. */ + if ( astOK ) { + class_init = 1; + +/* Obtain the variable argument list and pass it along with the options string + to the astVSet method to initialise the new ShiftMap's attributes. */ + va_start( args, options ); + astVSet( new, options, NULL, args ); + va_end( args ); + +/* If an error occurred, clean up by deleting the new object. */ + if ( !astOK ) new = astDelete( new ); + } + +/* Return an ID value for the new ShiftMap. */ + return astMakeId( new ); +} + +AstShiftMap *astInitShiftMap_( void *mem, size_t size, int init, + AstShiftMapVtab *vtab, const char *name, + int ncoord, const double *shift, int *status ) { +/* +*+ +* Name: +* astInitShiftMap + +* Purpose: +* Initialise a ShiftMap. + +* Type: +* Protected function. + +* Synopsis: +* #include "shiftmap.h" +* AstShiftMap *astInitShiftMap( void *mem, size_t size, int init, +* AstShiftMapVtab *vtab, const char *name, +* int ncoord, const double *shift ) + +* Class Membership: +* ShiftMap initialiser. + +* Description: +* This function is provided for use by class implementations to initialise +* a new ShiftMap object. It allocates memory (if necessary) to accommodate +* the ShiftMap plus any additional data associated with the derived class. +* It then initialises a ShiftMap 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 ShiftMap at the start of the memory passed via the +* "vtab" parameter. + +* Parameters: +* mem +* A pointer to the memory in which the ShiftMap is to be initialised. +* This must be of sufficient size to accommodate the ShiftMap data +* (sizeof(ShiftMap)) 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 ShiftMap (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 ShiftMap +* structure, so a valid value must be supplied even if not required for +* allocating memory. +* init +* A logical flag indicating if the ShiftMap'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 ShiftMap. +* 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). +* ncoord +* The number of coordinate values per point. +* shift +* Pointer to an array of shifts, one for each coordinate. + +* Returned Value: +* A pointer to the new ShiftMap. + +* 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: */ + AstShiftMap *new; /* Pointer to new ShiftMap */ + int axis; /* Axis index */ + +/* Check the global status. */ + if ( !astOK ) return NULL; + +/* If necessary, initialise the virtual function table. */ + if ( init ) astInitShiftMapVtab( vtab, name ); + +/* Initialise. */ + new = NULL; + +/* Initialise a Mapping structure (the parent class) as the first component + within the ShiftMap structure, allocating memory if necessary. Specify that + the Mapping should be defined in both the forward and inverse directions. */ + new = (AstShiftMap *) astInitMapping( mem, size, 0, + (AstMappingVtab *) vtab, name, + ncoord, ncoord, 1, 1 ); + + if ( astOK ) { + +/* Initialise the ShiftMap data. */ +/* ---------------------------- */ +/* Allocate memory to hold the shift for each axis. */ + new->shift = (double *) astMalloc( sizeof(double)*(size_t)ncoord ); + +/* Check the pointers can be used */ + if( astOK ){ + +/* Store the shift and scale for each axis. */ + for( axis = 0; axis < ncoord; axis++ ){ + (new->shift)[ axis ] = shift ? shift[ axis ] : AST__BAD; + } + + } + +/* If an error occurred, clean up by deleting the new ShiftMap. */ + if ( !astOK ) new = astDelete( new ); + } + +/* Return a pointer to the new ShiftMap. */ + return new; +} + +AstShiftMap *astLoadShiftMap_( void *mem, size_t size, + AstShiftMapVtab *vtab, const char *name, + AstChannel *channel, int *status ) { +/* +*+ +* Name: +* astLoadShiftMap + +* Purpose: +* Load a ShiftMap. + +* Type: +* Protected function. + +* Synopsis: +* #include "shiftmap.h" +* AstShiftMap *astLoadShiftMap( void *mem, size_t size, +* AstShiftMapVtab *vtab, const char *name, +* AstChannel *channel ) + +* Class Membership: +* ShiftMap loader. + +* Description: +* This function is provided to load a new ShiftMap 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 +* ShiftMap 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 ShiftMap at the start of the memory +* passed via the "vtab" parameter. + + +* Parameters: +* mem +* A pointer to the memory into which the ShiftMap is to be +* loaded. This must be of sufficient size to accommodate the +* ShiftMap data (sizeof(ShiftMap)) 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 ShiftMap (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 ShiftMap 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(AstShiftMap) is used instead. +* vtab +* Pointer to the start of the virtual function table to be +* associated with the new ShiftMap. If this is NULL, a pointer +* to the (static) virtual function table for the ShiftMap 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 "ShiftMap" is used instead. + +* Returned Value: +* A pointer to the new ShiftMap. + +* 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: */ + AstShiftMap *new; /* Pointer to the new ShiftMap */ + char buff[ KEY_LEN + 1 ]; /* Buffer for keyword string */ + int axis; /* Axis index */ + int ncoord; /* The number of coordinate axes */ + +/* 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 ShiftMap. In this case the + ShiftMap belongs to this class, so supply appropriate values to be + passed to the parent class loader (and its parent, etc.). */ + if ( !vtab ) { + size = sizeof( AstShiftMap ); + vtab = &class_vtab; + name = "ShiftMap"; + +/* If required, initialise the virtual function table for this class. */ + if ( !class_init ) { + astInitShiftMapVtab( 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 ShiftMap. */ + new = astLoadMapping( mem, size, (AstMappingVtab *) vtab, name, + channel ); + + if ( astOK ) { + +/* Get the number of axis for the mapping. */ + ncoord = astGetNin( (AstMapping *) new ); + +/* Allocate memory to hold the shifts. */ + new->shift = (double *) astMalloc( sizeof(double)*(size_t)ncoord ); + +/* Read input data. */ +/* ================ */ +/* Request the input Channel to read all the input data appropriate to + this class into the internal "values list". */ + astReadClassData( channel, "ShiftMap" ); + +/* Now read each individual data item from this list and use it to + initialise the appropriate instance variable(s) for this class. */ + +/* The shifts. */ + for( axis = 0; axis < ncoord; axis++ ){ + (void) sprintf( buff, "sft%d", axis + 1 ); + (new->shift)[ axis ] = astReadDouble( channel, buff, 0.0 ); + } + } + +/* If an error occurred, clean up by deleting the new ShiftMap. */ + if ( !astOK ) new = astDelete( new ); + +/* Return the new ShiftMap 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. */ + + + + + |