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author | William Joye <wjoye@cfa.harvard.edu> | 2018-01-09 19:28:07 (GMT) |
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committer | William Joye <wjoye@cfa.harvard.edu> | 2018-01-09 19:28:07 (GMT) |
commit | 3bfbbb90d4d6ebd44cc5eac38af24d1f78318a58 (patch) | |
tree | f278119398ae5d67a6a338705a76db420f6b8f7e /ast/pcdmap.c | |
parent | 1332d38f2805d986ea130e43218c0d2e870b4dc1 (diff) | |
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update ast 8.6.2
Diffstat (limited to 'ast/pcdmap.c')
-rw-r--r-- | ast/pcdmap.c | 3218 |
1 files changed, 3218 insertions, 0 deletions
diff --git a/ast/pcdmap.c b/ast/pcdmap.c new file mode 100644 index 0000000..7c043d6 --- /dev/null +++ b/ast/pcdmap.c @@ -0,0 +1,3218 @@ +/* +*class++ +* Name: +* PcdMap + +* Purpose: +* Apply 2-dimensional pincushion/barrel distortion. + +* Constructor Function: +c astPcdMap +f AST_PCDMAP + +* Description: +* A PcdMap is a non-linear Mapping which transforms 2-dimensional +* positions to correct for the radial distortion introduced by some +* cameras and telescopes. This can take the form either of pincushion +* or barrel distortion, and is characterized by a single distortion +* coefficient. +* +* A PcdMap is specified by giving this distortion coefficient and the +* coordinates of the centre of the radial distortion. The forward +* transformation of a PcdMap applies the distortion: +* +* RD = R * ( 1 + C * R * R ) +* +* where R is the undistorted radial distance from the distortion +* centre (specified by attribute PcdCen), RD is the radial distance +* from the same centre in the presence of distortion, and C is the +* distortion coefficient (given by attribute Disco). +* +* The inverse transformation of a PcdMap removes the distortion +* produced by the forward transformation. The expression used to derive +* R from RD is an approximate inverse of the expression above. + +* Inheritance: +* The PcdMap class inherits from the Mapping class. + +* Attributes: +* In addition to those attributes common to all Mappings, every +* PcdMap also has the following attributes: +* +* - Disco: PcdMap pincushion/barrel distortion coefficient +* - PcdCen(axis): Centre coordinates of pincushion/barrel distortion + +* Functions: +c The PcdMap class does not define any new functions beyond those +f The PcdMap 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: +* 18-MAY-1999 (DSB): +* Original version. +* 25-OCT-1999 (DSB): +* Fixed memory leak in MapMerge. +* 8-JAN-2003 (DSB): +* Changed private InitVtab method to protected astInitPcdMapVtab +* method. +* 23-AUG-2006 (DSB): +* Override astEqual. +* 23-APR-2015 (DSB): +* Improve MapMerge. If a PcdMap can merge with its next-but-one +* neighbour, then swap the PcdMap with its neighbour, so that +* it is then next its next-but-one neighbour, and then merge the +* two Mappings into a single Mapping. Previously, only the swap +* was performed - not the merger. And the swap was only performed +* if the intervening neighbour could not itself merge. This could +* result in an infinite simplification loop, which was detected by +* CmpMap and and aborted, resulting in no useful simplification. +*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 PcdMap + +/* 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 "globals.h" /* Thread-safe global data access */ +#include "object.h" /* Base Object class */ +#include "pointset.h" /* Sets of points/coordinates */ +#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 "pcdmap.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 AstPointSet *(* parent_transform)( AstMapping *, AstPointSet *, int, AstPointSet *, int * ); +static const char *(* parent_getattrib)( AstObject *, const char *, 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 * ); + +/* Define macros for accessing each item of thread specific global data. */ +#ifdef THREAD_SAFE + +/* Define how to initialise thread-specific globals. */ +#define GLOBAL_inits \ + globals->Class_Init = 0; \ + globals->GetAttrib_Buff[ 0 ] = 0; + +/* Create the function that initialises global data for this module. */ +astMAKE_INITGLOBALS(PcdMap) + +/* Define macros for accessing each item of thread specific global data. */ +#define class_init astGLOBAL(PcdMap,Class_Init) +#define class_vtab astGLOBAL(PcdMap,Class_Vtab) +#define getattrib_buff astGLOBAL(PcdMap,GetAttrib_Buff) + + + +/* If thread safety is not needed, declare and initialise globals at static + variables. */ +#else + +static char getattrib_buff[ 101 ]; + + +/* Define the class virtual function table and its initialisation flag + as static variables. */ +static AstPcdMapVtab 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. */ +AstPcdMap *astPcdMapId_( double, const double [2], const char *, ... ); + +/* Prototypes for Private Member Functions. */ +/* ======================================== */ + +static AstPointSet *Transform( AstMapping *, AstPointSet *, int, AstPointSet *, int * ); +static const char *GetAttrib( AstObject *, const char *, int * ); +static double GetDisco( AstPcdMap *, int * ); +static double GetPcdCen( AstPcdMap *, int, int * ); +static int CanMerge( AstMapping *, AstMapping *, int, int, int * ); +static int CanSwap( AstMapping *, AstMapping *, int, int, int * ); +static int Equal( AstObject *, AstObject *, int * ); +static int MapMerge( AstMapping *, int, int, int *, AstMapping ***, int **, int * ); +static int TestAttrib( AstObject *, const char *, int * ); +static int TestDisco( AstPcdMap *, int * ); +static int TestPcdCen( AstPcdMap *, int, int * ); +static void ClearAttrib( AstObject *, const char *, int * ); +static void ClearDisco( AstPcdMap *, int * ); +static void ClearPcdCen( AstPcdMap *, int, int * ); +static void Dump( AstObject *, AstChannel *, int * ); +static void PcdPerm( AstMapping **, int *, int, int * ); +static void PcdZoom( AstMapping **, int *, int, int * ); +static void PermGet( AstPermMap *, int **, int **, double **, int * ); +static void SetAttrib( AstObject *, const char *, int * ); +static void SetDisco( AstPcdMap *, double, int * ); +static void SetPcdCen( AstPcdMap *, int, double, int * ); + +/* Function Macros */ +/* =============== */ +/* Macros which return the maximum and minimum of two values. */ +#define MAX(aa,bb) ((aa)>(bb)?(aa):(bb)) +#define MIN(aa,bb) ((aa)<(bb)?(aa):(bb)) + +/* Macro to check for equality of floating point values. We cannot +compare bad values directory because of the danger of floating point +exceptions, so bad values are dealt with explicitly. */ +#define EQUAL(aa,bb) (((aa)==AST__BAD)?(((bb)==AST__BAD)?1:0):(((bb)==AST__BAD)?0:(fabs((aa)-(bb))<=1.0E5*MAX((fabs(aa)+fabs(bb))*DBL_EPSILON,DBL_MIN)))) + +/* +* +* Name: +* MAKE_CLEAR + +* Purpose: +* Implement a method to clear a single value in a multi-valued attribute. + +* Type: +* Private macro. + +* Synopsis: +* #include "pcdmap.h" +* MAKE_CLEAR(attr,component,assign,nval) + +* Class Membership: +* Defined by the PcdMap class. + +* Description: +* This macro expands to an implementation of a private member function of +* the form: +* +* static void Clear<Attribute>( AstPcdMap *this, int axis ) +* +* and an external interface function of the form: +* +* void astClear<Attribute>_( AstPcdMap *this, int axis ) +* +* which implement a method for clearing a single value in a specified +* multi-valued attribute for an axis of a PcdMap. + +* Parameters: +* attr +* The name of the attribute to be cleared, as it appears in the function +* name (e.g. PcdCen in "astClearPcdCen"). +* component +* The name of the class structure component that holds the attribute +* value. +* assign +* An expression that evaluates to the value to assign to the component +* to clear its value. +* nval +* Specifies the number of values in the multi-valued attribute. The +* "axis" values supplied to the created function should be in the +* range zero to (nval - 1). + +* Notes: +* - To avoid problems with some compilers, you should not leave any white +* space around the macro arguments. +* +*/ + +/* Define the macro. */ +#define MAKE_CLEAR(attr,component,assign,nval) \ +\ +/* Private member function. */ \ +/* ------------------------ */ \ +static void Clear##attr( AstPcdMap *this, int axis, int *status ) { \ +\ +/* Check the global error status. */ \ + if ( !astOK ) return; \ +\ +/* Validate the axis index. */ \ + if( axis < 0 || axis >= nval ){ \ + astError( AST__AXIIN, "%s(%s): Index (%d) is invalid for attribute " \ + #attr " - it should be in the range 1 to %d.", status, \ + "astClear" #attr, astGetClass( this ), \ + axis + 1, nval ); \ +\ +/* Report an error if the object has been cloned (i.e. has a reference \ + count that is greater than one). */ \ + } else if( astGetRefCount( this ) > 1 ) { \ + astError( AST__IMMUT, "astClear(%s): The " #attr "attribute of " \ + "the supplied %s cannot be cleared because the %s has " \ + "been cloned (programming error).", status, \ + astGetClass(this), astGetClass(this), astGetClass(this) ); \ +\ +/* Assign the "clear" value. */ \ + } else { \ + this->component[ axis ] = (assign); \ + } \ +} \ +\ +/* External interface. */ \ +/* ------------------- */ \ +void astClear##attr##_( AstPcdMap *this, int axis, int *status ) { \ +\ +/* Check the global error status. */ \ + if ( !astOK ) return; \ +\ +/* Invoke the required method via the virtual function table. */ \ + (**astMEMBER(this,PcdMap,Clear##attr))( this, axis, status ); \ +} + + +/* +* +* Name: +* MAKE_GET + +* Purpose: +* Implement a method to get a single value in a multi-valued attribute. + +* Type: +* Private macro. + +* Synopsis: +* #include "pcdmap.h" +* MAKE_GET(attr,type,bad_value,assign,nval) + +* Class Membership: +* Defined by the PcdMap class. + +* Description: +* This macro expands to an implementation of a private member function of +* the form: +* +* static <Type> Get<Attribute>( AstPcdMap *this, int axis ) +* +* and an external interface function of the form: +* +* <Type> astGet<Attribute>_( AstPcdMap *this, int axis ) +* +* which implement a method for getting a single value from a specified +* multi-valued attribute for an axis of a PcdMap. + +* Parameters: +* attr +* The name of the attribute whose value is to be obtained, as it +* appears in the function name (e.g. PcdCen in "astGetPcdCen"). +* type +* The C type of the attribute. +* bad_value +* A constant value to return if the global error status is set, or if +* the function fails. +* assign +* An expression that evaluates to the value to be returned. This can +* use the string "axis" to represent the zero-based value index. +* nval +* Specifies the number of values in the multi-valued attribute. The +* "axis" values supplied to the created function should be in the +* range zero to (nval - 1). + +* Notes: +* - To avoid problems with some compilers, you should not leave any white +* space around the macro arguments. +* +*/ + +/* Define the macro. */ +#define MAKE_GET(attr,type,bad_value,assign,nval) \ +\ +/* Private member function. */ \ +/* ------------------------ */ \ +static type Get##attr( AstPcdMap *this, int axis, int *status ) { \ + type result; /* Result to be returned */ \ +\ +/* Initialise */ \ + result = (bad_value); \ +\ +/* Check the global error status. */ \ + if ( !astOK ) return result; \ +\ +/* Validate the axis index. */ \ + if( axis < 0 || axis >= nval ){ \ + astError( AST__AXIIN, "%s(%s): Index (%d) is invalid for attribute " \ + #attr " - it should be in the range 1 to %d.", status, \ + "astGet" #attr, astGetClass( this ), \ + axis + 1, nval ); \ +\ +/* Assign the result value. */ \ + } else { \ + result = (assign); \ + } \ +\ +/* Check for errors and clear the result if necessary. */ \ + if ( !astOK ) result = (bad_value); \ +\ +/* Return the result. */ \ + return result; \ +} \ +/* External interface. */ \ +/* ------------------- */ \ +type astGet##attr##_( AstPcdMap *this, int axis, int *status ) { \ +\ +/* Check the global error status. */ \ + if ( !astOK ) return (bad_value); \ +\ +/* Invoke the required method via the virtual function table. */ \ + return (**astMEMBER(this,PcdMap,Get##attr))( this, axis, status ); \ +} + +/* +* +* Name: +* MAKE_SET + +* Purpose: +* Implement a method to set a single value in a multi-valued attribute. + +* Type: +* Private macro. + +* Synopsis: +* #include "pcdmap.h" +* MAKE_SET(attr,type,component,assign,nval) + +* Class Membership: +* Defined by the PcdMap class. + +* Description: +* This macro expands to an implementation of a private member function of +* the form: +* +* static void Set<Attribute>( AstPcdMap *this, int axis, <Type> value ) +* +* and an external interface function of the form: +* +* void astSet<Attribute>_( AstPcdMap *this, int axis, <Type> value ) +* +* which implement a method for setting a single value in a specified +* multi-valued attribute for a PcdMap. + +* Parameters: +* attr +* The name of the attribute to be set, as it appears in the function +* name (e.g. PcdCen in "astSetPcdCen"). +* type +* The C type of the attribute. +* component +* The name of the class structure component that holds the attribute +* value. +* assign +* An expression that evaluates to the value to be assigned to the +* component. +* nval +* Specifies the number of values in the multi-valued attribute. The +* "axis" values supplied to the created function should be in the +* range zero to (nval - 1). + +* Notes: +* - To avoid problems with some compilers, you should not leave any white +* space around the macro arguments. +*- +*/ + +/* Define the macro. */ +#define MAKE_SET(attr,type,component,assign,nval) \ +\ +/* Private member function. */ \ +/* ------------------------ */ \ +static void Set##attr( AstPcdMap *this, int axis, type value, int *status ) { \ +\ +/* Check the global error status. */ \ + if ( !astOK ) return; \ +\ +/* Validate the axis index. */ \ + if( axis < 0 || axis >= nval ){ \ + astError( AST__AXIIN, "%s(%s): Index (%d) is invalid for attribute " \ + #attr " - it should be in the range 1 to %d.", status, \ + "astSet" #attr, astGetClass( this ), \ + axis + 1, nval ); \ +\ +/* Report an error if the object has been cloned (i.e. has a reference \ + count that is greater than one). */ \ + } else if( astGetRefCount( this ) > 1 ) { \ + astError( AST__IMMUT, "astSet(%s): The " #attr "attribute of " \ + "the supplied %s cannot be changed because the %s has " \ + "been cloned (programming error).", status, \ + astGetClass(this), astGetClass(this), astGetClass(this) ); \ +\ +/* Store the new value in the structure component. */ \ + } else { \ + this->component[ axis ] = (assign); \ + } \ +} \ +\ +/* External interface. */ \ +/* ------------------- */ \ +void astSet##attr##_( AstPcdMap *this, int axis, type value, int *status ) { \ +\ +/* Check the global error status. */ \ + if ( !astOK ) return; \ +\ +/* Invoke the required method via the virtual function table. */ \ + (**astMEMBER(this,PcdMap,Set##attr))( this, axis, value, status ); \ +} + +/* +* +* Name: +* MAKE_TEST + +* Purpose: +* Implement a method to test if a single value has been set in a +* multi-valued attribute. + +* Type: +* Private macro. + +* Synopsis: +* #include "pcdmap.h" +* MAKE_TEST(attr,assign,nval) + +* Class Membership: +* Defined by the PcdMap class. + +* Description: +* This macro expands to an implementation of a private member function of +* the form: +* +* static int Test<Attribute>( AstPcdMap *this, int axis ) +* +* and an external interface function of the form: +* +* int astTest<Attribute>_( AstPcdMap *this, int axis ) +* +* which implement a method for testing if a single value in a specified +* multi-valued attribute has been set for a class. + +* Parameters: +* attr +* The name of the attribute to be tested, as it appears in the function +* name (e.g. PcdCen in "astTestPcdCen"). +* assign +* An expression that evaluates to 0 or 1, to be used as the returned +* value. This can use the string "axis" to represent the zero-based +* index of the value within the attribute. +* nval +* Specifies the number of values in the multi-valued attribute. The +* "axis" values supplied to the created function should be in the +* range zero to (nval - 1). + +* Notes: +* - To avoid problems with some compilers, you should not leave any white +* space around the macro arguments. +*- +*/ + +/* Define the macro. */ +#define MAKE_TEST(attr,assign,nval) \ +\ +/* Private member function. */ \ +/* ------------------------ */ \ +static int Test##attr( AstPcdMap *this, int axis, int *status ) { \ + int result; /* Value to return */ \ +\ +/* Initialise */ \ + result = 0; \ +\ +/* Check the global error status. */ \ + if ( !astOK ) return result; \ +\ +\ +/* Validate the axis index. */ \ + if( axis < 0 || axis >= nval ){ \ + astError( AST__AXIIN, "%s(%s): Index (%d) is invalid for attribute " \ + #attr " - it should be in the range 1 to %d.", status, \ + "astTest" #attr, astGetClass( this ), \ + axis + 1, nval ); \ +\ +/* Assign the result value. */ \ + } else { \ + result = (assign); \ + } \ +\ +/* Check for errors and clear the result if necessary. */ \ + if ( !astOK ) result = 0; \ +\ +/* Return the result. */ \ + return result; \ +} \ +/* External interface. */ \ +/* ------------------- */ \ +int astTest##attr##_( AstPcdMap *this, int axis, int *status ) { \ +\ +/* Check the global error status. */ \ + if ( !astOK ) return 0; \ +\ +/* Invoke the required method via the virtual function table. */ \ + return (**astMEMBER(this,PcdMap,Test##attr))( this, axis, status ); \ +} + +/* Member functions. */ +/* ================= */ +static int CanMerge( AstMapping *map1, AstMapping *map2, int inv1, int inv2, int *status ){ +/* +* +* Name: +* CanMerge + +* Purpose: +* Checks if two Mappings can be merged. + +* Type: +* Private function. + +* Synopsis: +* #include "pcdmap.h" +* int CanMerge( AstMapping *map1, AstMapping *map2, int inv1, int inv2, int *status ) + +* Class Membership: +* PcdMap internal utility function. + +* Description: +* This function checks the two supplied Mappings to see if they +* can be merged into a single Mapping. One of the pair must be a PcdMap. + +* Parameters: +* map1 +* A pointer to the first mapping. +* map2 +* A pointer to the second mapping. +* inv1 +* The invert flag to use with the first mapping. +* inv2 +* The invert flag to use with the second mapping. +* status +* Pointer to the inherited status variable. + +* Returned Value: +* 1 if the Mappings can be merged, zero otherwise. + +*/ + + AstPcdMap *pcd; /* Pointer to PcdMap Mapping */ + AstPcdMap *pcd2; /* Pointer to second PcdMap Mapping */ + AstMapping *nopcd; /* Pointer to non-PcdMap Mapping */ + const char *class1; /* Pointer to map1 class string */ + const char *class2; /* Pointer to map2 class string */ + const char *nopcd_class; /* Pointer to non-PcdMap class string */ + int invert[ 2 ]; /* Original invert flags */ + int ret; /* Returned flag */ + +/* Check the global error status. */ + if ( !astOK ) return 0; + +/* Initialise */ + ret = 0; + pcd = NULL; + nopcd = NULL; + +/* Temporarily set the Invert attributes of both Mappings to the supplied + values. */ + invert[ 0 ] = astGetInvert( map1 ); + astSetInvert( map1, inv1 ); + + invert[ 1 ] = astGetInvert( map2 ); + astSetInvert( map2, inv2 ); + +/* Get the classes of the two mappings. */ + class1 = astGetClass( map1 ); + class2 = astGetClass( map2 ); + if( astOK ){ + +/* Get pointers to the PcdMap and the non-PcdMap Mapping. */ + if( !strcmp( class1, "PcdMap" ) ){ + pcd = (AstPcdMap * ) map1; + nopcd = map2; + nopcd_class = class2; + } else if( !strcmp( class2, "PcdMap" ) ){ + nopcd = map1; + pcd = (AstPcdMap * ) map2; + nopcd_class = class1; + } else { + nopcd_class = "unusable"; + } + +/* The Mappings can merge if the other Mapping is a UnitMap. */ + if( !strcmp( nopcd_class, "UnitMap" ) ){ + ret = 1; + +/* They can also merge if the other Mapping is also a PcdMap, and is the + invert of the other. */ + } else if( !strcmp( nopcd_class, "PcdMap" ) ){ + pcd2 = (AstPcdMap *) nopcd; + +/* Check the distortion coefficients are equal. */ + if( EQUAL( astGetDisco( pcd ), astGetDisco( pcd2 ) ) ){ + +/* Check the axis 0 centres are equal. */ + if( EQUAL( astGetPcdCen( pcd, 0 ), astGetPcdCen( pcd2, 0 ) ) ){ + +/* Check the axis 1 centres are equal. */ + if( EQUAL( astGetPcdCen( pcd, 1 ), astGetPcdCen( pcd2, 1 ) ) ){ + +/* Check the Invert flags are different. */ + if( astGetInvert( pcd ) != astGetInvert( pcd2 ) ){ + +/* If the Mappings have passed all these tests, they can be merged. */ + ret = 1; + } + } + } + } + } + } + +/* Re-instate the original settings of the Invert attributes for the + supplied Mappings. */ + astSetInvert( map1, invert[ 0 ] ); + astSetInvert( map2, invert[ 1 ] ); + +/* Return the answer. */ + return astOK ? ret : 0; +} + +static int CanSwap( AstMapping *map1, AstMapping *map2, int inv1, int inv2, int *status ){ +/* +* Name: +* CanSwap + +* Purpose: +* Determine if two Mappings could be swapped. + +* Type: +* Private function. + +* Synopsis: +* #include "pcdmap.h" +* int CanSwap( AstMapping *map1, AstMapping *map2, int inv1, int inv2, int *status ) + +* Class Membership: +* PcdMap member function + +* Description: +* This function returns a flag indicating if the pair of supplied +* Mappings could be replaced by an equivalent pair of Mappings from the +* same classes as the supplied pair, but in reversed order. Each pair +* of Mappings is considered to be compounded in series. The supplied +* Mappings are not changed in any way. + +* Parameters: +* map1 +* The Mapping to be applied first. +* map2 +* The Mapping to be applied second. +* inv1 +* The invert flag to use with map1. A value of zero causes the forward +* mapping to be used, and a non-zero value causes the inverse +* mapping to be used. +* inv2 +* The invert flag to use with map2. +* status +* Pointer to the inherited status variable. + +* Returned Value: +* 1 if the Mappings could be swapped, 0 otherwise. + +* Notes: +* - One of the supplied pair of Mappings must be a PcdMap. +* - A value of 0 is returned if the two Mappings could be merged into +* a single Mapping. +* - A value of 0 is returned if an error has already occurred, or if +* this function should fail for any reason. +*/ + +/* Local Variables: */ + AstMapping *nopcd; /* Pointer to non-PcdMap Mapping */ + const char *class1; /* Pointer to map1 class string */ + const char *class2; /* Pointer to map2 class string */ + const char *nopcd_class; /* Pointer to non-PcdMap class string */ + double *consts; /* Pointer to constants array */ + int *inperm; /* Pointer to input axis permutation array */ + int *outperm; /* Pointer to output axis permutation array */ + int invert[ 2 ]; /* Original invert flags */ + int nin; /* No. of input coordinates for the PermMap */ + int nout; /* No. of output coordinates for the PermMap */ + int ret; /* Returned flag */ + +/* Check the global error status. */ + if ( !astOK ) return 0; + +/* Initialise */ + ret = 0; + +/* Temporarily set the Invert attributes of both Mappings to the supplied + values. */ + invert[ 0 ] = astGetInvert( map1 ); + astSetInvert( map1, inv1 ); + + invert[ 1 ] = astGetInvert( map2 ); + astSetInvert( map2, inv2 ); + +/* Get the classes of the two mappings. */ + class1 = astGetClass( map1 ); + class2 = astGetClass( map2 ); + if( astOK ){ + +/* Get a pointer to the non-PcdMap Mapping. */ + if( !strcmp( class1, "PcdMap" ) ){ + nopcd = map2; + nopcd_class = class2; + } else { + nopcd = map1; + nopcd_class = class1; + } + +/* If the other Mapping is a ZoomMap, the Mappings can be swapped. */ + if( !strcmp( nopcd_class, "ZoomMap" ) ){ + ret = 1; + +/* If it is a PermMap, the Mappings can be swapped so long as the PermMap + simply swaps the two axes. */ + } else if( !strcmp( nopcd_class, "PermMap" ) ){ + +/* Get the number of input and output coordinates for the PermMap. */ + nin = astGetNin( nopcd ); + nout = astGetNout( nopcd ); + +/* Must be 2-dimensional to swap. */ + if( nin == 2 && nout == 2 ) { + +/* Get the axis permutation arrays and constants array for the PermMap. */ + PermGet( (AstPermMap *) nopcd, &outperm, &inperm, &consts, status ); + if( astOK ) { + +/* If the PermMap simply swaps the 2 axes (in both direction) we can + swap the two mappings. */ + ret = ( outperm[0] == 1 && outperm[1] == 0 && + inperm[0] == 1 && inperm[1] == 0 ); + +/* Free the axis permutation and constants arrays. */ + outperm = (int *) astFree( (void *) outperm ); + inperm = (int *) astFree( (void *) inperm ); + consts = (double *) astFree( (void *) consts ); + } + } + } + } + +/* Re-instate the original settings of the Invert attributes for the + supplied Mappings. */ + astSetInvert( map1, invert[ 0 ] ); + astSetInvert( map2, invert[ 1 ] ); + +/* Return the answer. */ + return astOK ? ret : 0; +} + +static void ClearAttrib( AstObject *this_object, const char *attrib, int *status ) { +/* +* Name: +* ClearAttrib + +* Purpose: +* Clear an attribute value for a PcdMap. + +* Type: +* Private function. + +* Synopsis: +* #include "pcdmap.h" +* void ClearAttrib( AstObject *this, const char *attrib, int *status ) + +* Class Membership: +* PcdMap member function (over-rides the astClearAttrib protected +* method inherited from the Mapping class). + +* Description: +* This function clears the value of a specified attribute for a +* PcdMap, so that the default value will subsequently be used. + +* Parameters: +* this +* Pointer to the PcdMap. +* 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: */ + AstPcdMap *this; /* Pointer to the PcdMap structure */ + int axis; /* Axis number */ + int len; /* Length of attrib string */ + int nc; /* No. characters read by astSscanf */ + +/* Check the global error status. */ + if ( !astOK ) return; + +/* Obtain a pointer to the PcdMap structure. */ + this = (AstPcdMap *) this_object; + +/* Obtain the length of the "attrib" string. */ + len = strlen( attrib ); + +/* Check the attribute name and clear the appropriate attribute. */ + +/* PcdCen(axis). */ +/* ------------- */ + if ( nc = 0, + ( 1 == astSscanf( attrib, "pcdcen(%d)%n", &axis, &nc ) ) + && ( nc >= len ) ) { + astClearPcdCen( this, axis - 1 ); + +/* PcdCen. */ +/* ------- */ + } else if ( !strcmp( attrib, "pcdcen" ) ) { + astClearPcdCen( this, 0 ); + astClearPcdCen( this, 1 ); + +/* Disco. */ +/* ------ */ + } else if ( !strcmp( attrib, "disco" ) ) { + astClearDisco( this ); + +/* 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 PcdMaps are equivalent. + +* Type: +* Private function. + +* Synopsis: +* #include "pcdmap.h" +* int Equal( AstObject *this, AstObject *that, int *status ) + +* Class Membership: +* PcdMap 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 PcdMaps are equivalent. + +* Parameters: +* this +* Pointer to the first Object (a PcdMap). +* that +* Pointer to the second Object. +* status +* Pointer to the inherited status variable. + +* Returned Value: +* One if the PcdMaps 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: */ + AstPcdMap *that; + AstPcdMap *this; + int result; + +/* Initialise. */ + result = 0; + +/* Check the global error status. */ + if ( !astOK ) return result; + +/* Obtain pointers to the two PcdMap structures. */ + this = (AstPcdMap *) this_object; + that = (AstPcdMap *) that_object; + +/* Check the second object is a PcdMap. We know the first is a + PcdMap since we have arrived at this implementation of the virtual + function. */ + if( astIsAPcdMap( that ) ) { + +/* Check the Invert flags for the two PcdMaps are equal. */ + if( astGetInvert( this ) == astGetInvert( that ) ) { + +/* Check all the attributes are equal. */ + if( astEQUAL( this->pcdcen[0], that->pcdcen[0] ) && + astEQUAL( this->pcdcen[1], that->pcdcen[1] ) && + astEQUAL( this->disco, that->disco ) ) { + result = 1; + } + } + } + +/* 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 PcdMap. + +* Type: +* Private function. + +* Synopsis: +* #include "pcdmap.h" +* const char *GetAttrib( AstObject *this, const char *attrib, int *status ) + +* Class Membership: +* PcdMap member function (over-rides the protected astGetAttrib +* method inherited from the Mapping class). + +* Description: +* This function returns a pointer to the value of a specified +* attribute for a PcdMap, formatted as a character string. + +* Parameters: +* this +* Pointer to the PcdMap. +* 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 PcdMap, 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 PcdMap. 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: */ + astDECLARE_GLOBALS /* Pointer to thread-specific global data */ + AstPcdMap *this; /* Pointer to the PcdMap structure */ + const char *result; /* Pointer value to return */ + double dval; /* Double attribute value */ + int axis; /* Axis number */ + int len; /* Length of attrib string */ + int nc; /* No. characters read by astSscanf */ + +/* Initialise. */ + result = NULL; + +/* Check the global error status. */ + if ( !astOK ) return result; + +/* Get a pointer to the thread specific global data structure. */ + astGET_GLOBALS(this_object); + +/* Obtain a pointer to the PcdMap structure. */ + this = (AstPcdMap *) 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 "getattrib_buff" as a null terminated string in an appropriate + format. Set "result" to point at the result string. */ + +/* Disco. */ +/* ------ */ + if ( !strcmp( attrib, "disco" ) ) { + dval = astGetDisco( this ); + if ( astOK ) { + (void) sprintf( getattrib_buff, "%.*g", AST__DBL_DIG, dval ); + result = getattrib_buff; + } + +/* PcdCen(axis). */ +/* ------------- */ + } else if ( nc = 0, + ( 1 == astSscanf( attrib, "pcdcen(%d)%n", &axis, &nc ) ) + && ( nc >= len ) ) { + dval = astGetPcdCen( this, axis - 1 ); + if ( astOK ) { + (void) sprintf( getattrib_buff, "%.*g", AST__DBL_DIG, dval ); + result = getattrib_buff; + } + +/* PcdCen. */ +/* ------- */ + } else if ( !strcmp( attrib, "pcdcen" ) ) { + dval = astGetPcdCen( this, 0 ); + if ( astOK ) { + (void) sprintf( getattrib_buff, "%.*g", AST__DBL_DIG, dval ); + result = getattrib_buff; + } + +/* 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; +} + +void astInitPcdMapVtab_( AstPcdMapVtab *vtab, const char *name, int *status ) { +/* +*+ +* Name: +* astInitPcdMapVtab + +* Purpose: +* Initialise a virtual function table for a PcdMap. + +* Type: +* Protected function. + +* Synopsis: +* #include "pcdmap.h" +* void astInitPcdMapVtab( AstPcdMapVtab *vtab, const char *name ) + +* Class Membership: +* PcdMap vtab initialiser. + +* Description: +* This function initialises the component of a virtual function +* table which is used by the PcdMap 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 astIsAPcdMap) 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. */ + vtab->ClearDisco = ClearDisco; + vtab->SetDisco = SetDisco; + vtab->GetDisco = GetDisco; + vtab->TestDisco = TestDisco; + vtab->ClearPcdCen = ClearPcdCen; + vtab->SetPcdCen = SetPcdCen; + vtab->GetPcdCen = GetPcdCen; + vtab->TestPcdCen = TestPcdCen; + +/* 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_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; + object->Equal = Equal; + + parent_transform = mapping->Transform; + mapping->Transform = Transform; + +/* Store replacement pointers for methods which will be over-ridden by + new member functions implemented here. */ + mapping->MapMerge = MapMerge; + +/* Declare the class dump function.*/ + astSetDump( vtab, Dump, "PcdMap", "Apply pincushion distortion" ); + +/* 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 PcdMap. + +* 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: +* PcdMap 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 PcdMap 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 PcdMap 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 PcdMap which is to be merged with +* its neighbours. This should be a cloned copy of the PcdMap +* pointer contained in the array element "(*map_list)[where]" +* (see below). This pointer will not be annulled, and the +* PcdMap it identifies will not be modified by this function. +* where +* Index in the "*map_list" array (below) at which the pointer +* to the nominated PcdMap 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: */ + AstMapping **maplt; /* New mappings list pointer */ + AstMapping *map2; /* First mapping to check */ + AstMapping *newmap; /* Pointer to replacement Mapping */ + AstMapping *mc[2]; /* Copies of supplied Mappings to swap */ + AstMapping *smc0; /* Simplied Mapping */ + AstMapping *smc1; /* Simplied Mapping */ + const char *class1; /* Pointer to first Mapping class string */ + const char *class2; /* Pointer to second Mapping class string */ + const char *nclass; /* Pointer to neighbouring Mapping class */ + int i1; /* Index of first PcdMap to merge */ + int i2; /* Index of last PcdMap to merge */ + int i; /* Loop counter */ + int ic[2]; /* Copies of supplied invert flags to swap */ + int invert; /* Should the inverted Mapping be used? */ + int *invlt; /* New invert flags list pointer */ + int nmapt; /* No. of Mappings in list */ + int nstep1; /* No. of Mappings backwards to next mergable Mapping */ + int nstep2; /* No. of Mappings forward to next mergable Mapping */ + int result; /* Result value to return */ + int swaphi; /* Can PcdMap be swapped with higher neighbour? */ + int swaplo; /* Can PcdMap be swapped with lower neighbour? */ + +/* Initialise. */ + result = -1; + +/* Check the global error status. */ + if ( !astOK ) return result; + +/* Initialise variables to avoid "used of uninitialised variable" + messages from dumb compilers. */ + i1 = 0; + i2 = 0; + +/* First of all, see if the PcdMap can be replaced by a simpler Mapping, + without reference to the neighbouring Mappings in the list. */ +/* ======================================================================*/ +/* If the distortion coefficient in the PcdMap is zero, the PcdMap can be + replaced by a UnitMap. */ + if( EQUAL( astGetDisco( (AstPcdMap *) ( *map_list )[ where ] ), 0.0 ) ){ + +/* Annul the PcdMap pointer in the list and replace it with a UnitMap + pointer, and indicate that the forward transformation of the returned + UnitMap should be used. */ + (void) astAnnul( ( *map_list )[ where ] ); + ( *map_list )[ where ] = (AstMapping *) astUnitMap( 2, "", status ); + ( *invert_list )[ where ] = 0; + +/* Return the index of the first modified element. */ + result = where; + +/* If the PcdMap itself could not be simplified, see if it can be merged + with the Mappings on either side of it in the list. */ + } else { + +/* Store the classes of the neighbouring Mappings in the list. */ + class1 = ( where > 0 ) ? astGetClass( ( *map_list )[ where - 1 ] ) : NULL; + class2 = ( where < *nmap - 1 ) ? astGetClass( ( *map_list )[ where + 1 ] ) : NULL; + +/* In series. */ +/* ========== */ + if ( series ) { + +/* We first look to see if the PcdMap can be merged with one of its + neighbours, resulting in a reduction of one in the number of Mappings + in the list. A PcdMap can only merge directly with its own inverse, or + a UnitMap. */ + if( class1 && CanMerge( ( *map_list )[ where - 1 ], + ( *map_list )[ where ], + ( *invert_list )[ where - 1 ], + ( *invert_list )[ where ], status ) ){ + nclass = class1; + i1 = where - 1; + i2 = where; + + } else if( class2 && CanMerge( ( *map_list )[ where ], + ( *map_list )[ where + 1 ], + ( *invert_list )[ where ], + ( *invert_list )[ where + 1 ], status ) ){ + nclass = class2; + i1 = where; + i2 = where + 1; + + } else { + nclass = NULL; + } + +/* If the PcdMap can merge with one of its neighbours, create the merged + Mapping. */ + if( nclass ){ + +/* If the neighbour is a PcdMap, it must be the inverse of the nominated + Mapping, and so they merge to form a UnitMap. */ + if( !strcmp( nclass, "PcdMap" ) ){ + newmap = (AstMapping *) astUnitMap( 2, "", status ); + invert = 0; + +/* If the neighbour is a UnitMap, they merge to form a clone of the + nominated PcdMap. */ + } else { + newmap = (AstMapping *) astClone( ( *map_list )[ where ] ); + invert = ( *invert_list )[ where ]; + } + +/* If succesfull... */ + if( astOK ){ + +/* Annul the first of the two Mappings, and replace it with the merged + Mapping. Also set the invert flag. */ + (void) astAnnul( ( *map_list )[ i1 ] ); + ( *map_list )[ i1 ] = newmap; + ( *invert_list )[ i1 ] = invert; + +/* Annul the second of the two Mappings, and shuffle down the rest of the + list to fill the gap. */ + (void) astAnnul( ( *map_list )[ i2 ] ); + for ( i = i2 + 1; i < *nmap; i++ ) { + ( *map_list )[ i - 1 ] = ( *map_list )[ i ]; + ( *invert_list )[ i - 1 ] = ( *invert_list )[ i ]; + } + +/* Clear the vacated element at the end. */ + ( *map_list )[ *nmap - 1 ] = NULL; + ( *invert_list )[ *nmap - 1 ] = 0; + +/* Decrement the Mapping count and return the index of the first + modified element. */ + ( *nmap )--; + result = i1; + + } + +/* If the PcdMap could not merge directly with either of its neighbours, + we consider whether it would be worthwhile to swap the PcdMap with + either of its neighbours. This can only be done for certain classes + of Mapping (ZoomMaps & some PermMaps), and will usually require both + Mappings to be modified (unless they are commutative). The advantage of + swapping the order of the Mappings is that it may result in the PcdMap + being adjacent to a Mapping with which it can merge directly on the next + invocation of this function, thus reducing the number of Mappings + in the list. */ + } else { + +/* Set a flag if we could swap the PcdMap with its higher neighbour. */ + if( where + 1 < *nmap ){ + swaphi = CanSwap( ( *map_list )[ where ], + ( *map_list )[ where + 1 ], + ( *invert_list )[ where ], + ( *invert_list )[ where + 1 ], status ); + } else { + swaphi = 0; + } + +/* If so, step through each of the Mappings which follow the PcdMap, + looking for a Mapping with which the PcdMap could merge directly. Stop + when such a Mapping is found, or if a Mapping is found with which the + PcdMap could definitely not swap. Note the number of Mappings which + separate the PcdMap from the Mapping with which it could merge (if + any). */ + nstep2 = -1; + if( swaphi ){ + for( i2 = where + 1; i2 < *nmap; i2++ ){ + +/* See if we may be able to merge with this Mapping. If so, note the number + of steps between the two Mappings and leave the loop. */ + nclass = astGetClass( ( *map_list )[ i2 ] ); + + if( !strcmp( nclass, "UnitMap" ) || + !strcmp( nclass, "PcdMap" ) ){ + nstep2 = i2 - where - 1; + break; + } + +/* If there is no chance that we can swap with this Mapping, leave the loop + with -1 for the number of steps to indicate that no merging is possible. + PcdMaps can swap with ZoomMaps and some PermMaps. */ + if( strcmp( nclass, "ZoomMap" ) && + strcmp( nclass, "PermMap" ) ) { + break; + } + + } + + } + +/* Do the same working forward from the PcdMap towards the start of the map + list. */ + if( where > 0 ){ + swaplo = CanSwap( ( *map_list )[ where - 1 ], + ( *map_list )[ where ], + ( *invert_list )[ where - 1 ], + ( *invert_list )[ where ], status ); + } else { + swaplo = 0; + } + + nstep1 = -1; + if( swaplo ){ + for( i1 = where - 1; i1 >= 0; i1-- ){ + + nclass = astGetClass( ( *map_list )[ i1 ] ); + + if( !strcmp( nclass, "UnitMap" ) || + !strcmp( nclass, "PcdMap" ) ){ + nstep1 = where - 1 - i1; + break; + } + + if( strcmp( nclass, "ZoomMap" ) && + strcmp( nclass, "PermMap" ) ) { + break; + } + + } + + } + +/* Choose which neighbour to swap with so that the PcdMap moves towards the + nearest Mapping with which it can merge. */ + if( nstep1 != -1 && ( nstep2 == -1 || nstep2 > nstep1 ) ){ + nclass = class1; + i1 = where - 1; + i2 = where; + } else if( nstep2 != -1 ){ + nclass = class2; + i1 = where; + i2 = where + 1; + } else { + nclass = NULL; + } + +/* If there is a target Mapping in the list with which the PcdMap could + merge, replace the supplied Mappings with swapped Mappings to bring a + PcdMap closer to the target Mapping. */ + if( nclass ){ + +/* Swap the Mappings. */ + if( !strcmp( nclass, "ZoomMap" ) ){ + PcdZoom( (*map_list) + i1, (*invert_list) + i1, where - i1, status ); + + } else if( !strcmp( nclass, "PermMap" ) ){ + PcdPerm( (*map_list) + i1, (*invert_list) + i1, where - i1, status ); + } + +/* And then merge them. */ + if( where == i1 && where + 1 < *nmap ) { /* Merging upwards */ + map2 = astClone( (*map_list)[ where + 1 ] ); + nmapt = *nmap - where - 1; + maplt = *map_list + where + 1; + invlt = *invert_list + where + 1; + + (void) astMapMerge( map2, 0, series, &nmapt, &maplt, &invlt ); + map2 = astAnnul( map2 ); + *nmap = where + 1 + nmapt; + + } else if( where - 2 >= 0 ) { /* Merging downwards */ + map2 = astClone( (*map_list)[ where - 2 ] ); + nmapt = *nmap - where + 2; + maplt = *map_list + where - 2 ; + invlt = *invert_list + where - 2; + + (void) astMapMerge( map2, 0, series, &nmapt, &maplt, &invlt ); + map2 = astAnnul( map2 ); + *nmap = where - 2 + nmapt; + } + + result = i1; + +/* If there is no Mapping available for merging, it may still be + advantageous to swap with a neighbour because the swapped Mapping may + be simpler than the original Mappings. */ + } else if( swaphi || swaplo ) { + +/* Try swapping with each possible neighbour in turn. */ + for( i = 0; i < 2; i++ ) { + +/* Set up the class and pointers for the mappings to be swapped, first + the lower neighbour, then the upper neighbour. */ + if( i == 0 && swaplo ){ + nclass = class1; + i1 = where - 1; + i2 = where; + + } else if( i == 1 && swaphi ){ + nclass = class2; + i1 = where; + i2 = where + 1; + + } else { + nclass = NULL; + } + +/* If we have a Mapping to swap with... */ + if( nclass ) { + +/* Take copies of the Mapping and Invert flag arrays so we do not change + the supplied values. */ + mc[ 0 ] = (AstMapping *) astCopy( ( (*map_list) + i1 )[0] ); + mc[ 1 ] = (AstMapping *) astCopy( ( (*map_list) + i1 )[1] ); + ic[ 0 ] = ( (*invert_list) + i1 )[0]; + ic[ 1 ] = ( (*invert_list) + i1 )[1]; + +/* Swap these Mappings. */ + if( !strcmp( nclass, "ZoomMap" ) ){ + PcdZoom( mc, ic, where - i1, status ); + } else if( !strcmp( nclass, "PermMap" ) ){ + PcdPerm( mc, ic, where - i1, status ); + } + +/* If neither of the swapped Mappings can be simplified further, then there + is no point in swapping the Mappings, so just annul the map copies. */ + smc0 = astSimplify( mc[0] ); + smc1 = astSimplify( mc[1] ); + + if( astGetClass( smc0 ) == astGetClass( mc[0] ) && + astGetClass( smc1 ) == astGetClass( mc[1] ) ) { + + mc[ 0 ] = (AstMapping *) astAnnul( mc[ 0 ] ); + mc[ 1 ] = (AstMapping *) astAnnul( mc[ 1 ] ); + +/* If one or both of the swapped Mappings could be simplified, then annul + the supplied Mappings and return the swapped mappings, storing the index + of the first modified Mapping. */ + } else { + (void ) astAnnul( ( (*map_list) + i1 )[0] ); + (void ) astAnnul( ( (*map_list) + i1 )[1] ); + + ( (*map_list) + i1 )[0] = mc[ 0 ]; + ( (*map_list) + i1 )[1] = mc[ 1 ]; + + ( (*invert_list) + i1 )[0] = ic[ 0 ]; + ( (*invert_list) + i1 )[1] = ic[ 1 ]; + + result = i1; + break; + } + +/* Annul the simplied Mappings */ + smc0 = astAnnul( smc0 ); + smc1 = astAnnul( smc1 ); + + } + } + } + } + +/* In parallel. */ +/* ============ */ +/* PcdMaps cannot combine in parallel with any other Mappings. */ + } + } + +/* Return the result. */ + return result; +} + +static void PermGet( AstPermMap *map, int **outperm, int **inperm, + double **consts, int *status ){ +/* +* Name: +* PermGet + +* Purpose: +* Get the axis permutation and constants array for a PermMap. + +* Type: +* Private function. + +* Synopsis: +* #include "pcdmap.h" +* void PermGet( AstPermMap *map, int **outperm, int **inperm, +* double **const, int *status ) + +* Class Membership: +* PcdMap member function + +* Description: +* This function returns axis permutation and constants arrays which can +* be used to create a PermMap which is equivalent to the supplied PermMap. + +* Parameters: +* map +* The PermMap. +* outperm +* An address at which to return a popinter to an array of ints +* holding the output axis permutation array. The array should be +* released using astFree when no longer needed. +* inperm +* An address at which to return a popinter to an array of ints +* holding the input axis permutation array. The array should be +* released using astFree when no longer needed. +* consts +* An address at which to return a popinter to an array of doubles +* holding the constants array. The array should be released using +* astFree when no longer needed. +* status +* Pointer to the inherited status variable. + +* Notes: +* - NULL pointers are returned if an error has already occurred, or if +* this function should fail for any reason. +*/ + +/* Local Variables: */ + AstPointSet *pset1; /* PointSet holding input positions for PermMap */ + AstPointSet *pset2; /* PointSet holding output positions for PermMap */ + double **ptr1; /* Pointer to pset1 data */ + double **ptr2; /* Pointer to pset2 data */ + double *cnst; /* Pointer to constants array */ + double cn; /* Potential new constant value */ + double ip; /* Potential output axis index */ + double op; /* Potential input axis index */ + int *inprm; /* Pointer to input axis permutation array */ + int *outprm; /* Pointer to output axis permutation array */ + int i; /* Axis count */ + int nc; /* Number of constants stored so far */ + int nin; /* No. of input coordinates for the PermMap */ + int nout; /* No. of output coordinates for the PermMap */ + +/* Initialise. */ + if( outperm ) *outperm = NULL; + if( inperm ) *inperm = NULL; + if( consts ) *consts = NULL; + +/* Check the global error status and the supplied pointers. */ + if ( !astOK || !outperm || !inperm || !consts ) return; + +/* Initialise variables to avoid "used of uninitialised variable" + messages from dumb compilers. */ + nc = 0; + +/* Get the number of input and output axes for the supplied PermMap. */ + nin = astGetNin( map ); + nout = astGetNout( map ); + +/* Allocate the memory for the returned arrays. */ + outprm = (int *) astMalloc( sizeof( int )* (size_t) nout ); + inprm = (int *) astMalloc( sizeof( int )* (size_t) nin ); + cnst = (double *) astMalloc( sizeof( double )* (size_t) ( nout + nin ) ); + +/* Returned the pointers to these arrays.*/ + *outperm = outprm; + *inperm = inprm; + *consts = cnst; + +/* Create two PointSets, each holding two points, which can be used for + input and output positions with the PermMap. */ + pset1 = astPointSet( 2, nin, "", status ); + pset2 = astPointSet( 2, nout, "", status ); + +/* Set up the two input positions to be [0,1,2...] and [-1,-1,-1,...]. The + first position is used to enumerate the axes, and the second is used to + check for constant axis values. */ + ptr1 = astGetPoints( pset1 ); + if( astOK ){ + for( i = 0; i < nin; i++ ){ + ptr1[ i ][ 0 ] = ( double ) i; + ptr1[ i ][ 1 ] = -1.0; + } + } + +/* Use the PermMap to transform these positions in the forward direction. */ + (void) astTransform( map, pset1, 1, pset2 ); + +/* Look at the mapped positions to determine the output axis permutation + array. */ + ptr2 = astGetPoints( pset2 ); + if( astOK ){ + +/* No constant axis valeus found yet. */ + nc = 0; + +/* Do each output axis. */ + for( i = 0; i < nout; i++ ){ + +/* If the output axis value is copied from an input axis value, the index + of the appropriate input axis will be in the mapped first position. */ + op = ptr2[ i ][ 0 ]; + +/* If the output axis value is assigned a constant value, the result of + mapping the two different input axis values will be the same. */ + cn = ptr2[ i ][ 1 ]; + if( op == cn ) { + +/* We have found another constant. Store it in the constants array, and + store the index of the constant in the output axis permutation array. */ + cnst[ nc ] = cn; + outprm[ i ] = -( nc + 1 ); + nc++; + +/* If the output axis values are different, then the output axis value + must be copied from the input axis value. */ + } else { + outprm[ i ] = (int) ( op + 0.5 ); + } + } + } + +/* Now do the same thing to determine the input permutation array. */ + if( astOK ){ + for( i = 0; i < nout; i++ ){ + ptr2[ i ][ 0 ] = ( double ) i; + ptr2[ i ][ 1 ] = -1.0; + } + } + + (void) astTransform( map, pset2, 0, pset1 ); + + if( astOK ){ + + for( i = 0; i < nin; i++ ){ + + ip = ptr1[ i ][ 0 ]; + cn = ptr1[ i ][ 1 ]; + if( ip == cn ) { + + cnst[ nc ] = cn; + inprm[ i ] = -( nc + 1 ); + nc++; + + } else { + inprm[ i ] = (int) ( ip + 0.5 ); + } + } + } + +/* Annul the PointSets. */ + pset1 = astAnnul( pset1 ); + pset2 = astAnnul( pset2 ); + +/* If an error has occurred, attempt to free the returned arrays. */ + if( !astOK ) { + *outperm = (int *) astFree( (void *) *outperm ); + *inperm = (int *) astFree( (void *) *inperm ); + *consts = (double *) astFree( (void *) *consts ); + } + +/* Return. */ + return; +} + +static void SetAttrib( AstObject *this_object, const char *setting, int *status ) { +/* +* Name: +* SetAttrib + +* Purpose: +* Set an attribute value for a PcdMap. + +* Type: +* Private function. + +* Synopsis: +* #include "pcdmap.h" +* void SetAttrib( AstObject *this, const char *setting, int *status ) + +* Class Membership: +* PcdMap member function (over-rides the astSetAttrib protected +* method inherited from the Mapping class). + +* Description: +* This function assigns an attribute value for a PcdMap, 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 PcdMap. +* setting +* Pointer to a null terminated string specifying the new attribute +* value. +* status +* Pointer to the inherited status variable. +*/ + +/* Local Variables: */ + AstPcdMap *this; /* Pointer to the PcdMap structure */ + double dval; /* Double attribute value */ + int axis; /* Index for the axis */ + 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 PcdMap structure. */ + this = (AstPcdMap *) this_object; + +/* Obtain the length of the setting string. */ + len = (int) 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. */ + +/* Disco. */ +/* ------ */ + if ( nc = 0, + ( 1 == astSscanf( setting, "disco= %lg %n", &dval, &nc ) ) + && ( nc >= len ) ) { + astSetDisco( this, dval ); + +/* PcdCen(axis). */ +/* ------------ */ + } else if ( nc = 0, + ( 2 == astSscanf( setting, "pcdcen(%d)= %lg %n", + &axis, &dval, &nc ) ) + && ( nc >= len ) ) { + astSetPcdCen( this, axis - 1, dval ); + +/* PcdCen. */ +/* ------- */ + } else if ( nc = 0, + ( 1 == astSscanf( setting, "pcdcen= %lg %n", &dval, &nc ) ) + && ( nc >= len ) ) { + astSetPcdCen( this, 0, dval ); + astSetPcdCen( this, 1, dval ); + +/* If the attribute is still not recognised, pass it on to the parent + method for further interpretation. */ + } else { + (*parent_setattrib)( this_object, setting, status ); + } + +} + +static int TestAttrib( AstObject *this_object, const char *attrib, int *status ) { +/* +* Name: +* TestAttrib + +* Purpose: +* Test if a specified attribute value is set for a PcdMap. + +* Type: +* Private function. + +* Synopsis: +* #include "pcdmap.h" +* int TestAttrib( AstObject *this, const char *attrib, int *status ) + +* Class Membership: +* PcdMap member function (over-rides the astTestAttrib protected +* method inherited from the Mapping class). + +* Description: +* This function returns a boolean result (0 or 1) to indicate whether +* a value has been set for one of a PcdMap's attributes. + +* Parameters: +* this +* Pointer to the PcdMap. +* 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: +* - 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: */ + AstPcdMap *this; /* Pointer to the PcdMap structure */ + int axis; /* Axis number */ + int len; /* Length of attrib string */ + int nc; /* No. characters read by astSscanf */ + int result; /* Result value to return */ + +/* Initialise. */ + result = 0; + +/* Check the global error status. */ + if ( !astOK ) return result; + +/* Obtain a pointer to the PcdMap structure. */ + this = (AstPcdMap *) this_object; + +/* Obtain the length of the attrib string. */ + len = strlen( attrib ); + +/* Check the attribute name and test the appropriate attribute. */ + +/* Disco. */ +/* ------ */ + if ( !strcmp( attrib, "disco" ) ) { + result = astTestDisco( this ); + +/* PcdCen. */ +/* ------- */ + } else if ( !strcmp( attrib, "pcdcen" ) ) { + result = astTestPcdCen( this, 0 ); + +/* PcdCen(axis). */ +/* ---------- */ + } else if ( nc = 0, + ( 1 == astSscanf( attrib, "pcdcen(%d)%n", &axis, &nc ) ) + && ( nc >= len ) ) { + result = astTestPcdCen( this, axis - 1 ); + +/* 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, AstPointSet *in, + int forward, AstPointSet *out, int *status ) { +/* +* Name: +* Transform + +* Purpose: +* Apply a PcdMap to transform a set of points. + +* Type: +* Private function. + +* Synopsis: +* #include "pcdmap.h" +* AstPointSet *Transform( AstMapping *this, AstPointSet *in, +* int forward, AstPointSet *out, int *status ) + +* Class Membership: +* PcdMap member function (over-rides the astTransform protected +* method inherited from the Mapping class). + +* Description: +* This function takes a PcdMap 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 PcdMap. +* 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 PcdMap 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 */ + AstPcdMap *map; /* Pointer to PcdMap to be applied */ + double **ptr_in; /* Pointer to input coordinate data */ + double **ptr_out; /* Pointer to output coordinate data */ + double *axin_0; /* Pointer to next input axis 0 value */ + double *axin_1; /* Pointer to next input axis 1 value */ + double *axout_0; /* Pointer to next output axis 0 value */ + double *axout_1; /* Pointer to next output axis 1 value */ + int npoint; /* Number of points */ + int point; /* Loop counter for points */ + double dx; /* Undistorted X increment from centre */ + double dy; /* Undistorted Y increment from centre */ + double dxp; /* Distorted X increment from centre */ + double dyp; /* Distorted Y increment from centre */ + double disco; /* Distortion coefficient */ + double cen0; /* Centre of distortion on axis 0 */ + double cen1; /* Centre of distortion on axis 1 */ + double cr2; /* Constant */ + double a; /* Constant */ + double cr2a2; /* Constant */ + double f; /* Expansion factor */ + +/* Check the global error status. */ + if ( !astOK ) return NULL; + +/* Obtain a pointer to the PcdMap. */ + map = (AstPcdMap *) 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. */ + 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; + +/* Get the distortion coefficient and centre. */ + disco = astGetDisco( map ); + cen0 = astGetPcdCen( map, 0 ); + cen1 = astGetPcdCen( map, 1 ); + +/* Perform coordinate arithmetic. */ +/* ------------------------------ */ + if( astOK ){ + +/* Store pointers to the first input and output values on both axes. */ + axin_0 = ptr_in[ 0 ]; + axin_1 = ptr_in[ 1 ]; + axout_0 = ptr_out[ 0 ]; + axout_1 = ptr_out[ 1 ]; + +/* First deal with forward transformations. */ + if( forward ){ + + for( point = 0; point < npoint; point++ ){ + if( *axin_0 != AST__BAD && *axin_1 != AST__BAD ){ + dx = ( *axin_0 - cen0 ); + dy = ( *axin_1 - cen1 ); + f = 1.0 + disco*( dx*dx + dy*dy ); + dxp = dx*f; + dyp = dy*f; + *(axout_0++) = dxp + cen0; + *(axout_1++) = dyp + cen1; + + } else { + *(axout_0++) = AST__BAD; + *(axout_1++) = AST__BAD; + } + axin_0++; + axin_1++; + } + +/* Now deal with inverse transformations. */ + } else { + + for( point = 0; point < npoint; point++ ){ + if( *axin_0 != AST__BAD && *axin_1 != AST__BAD ){ + dxp = ( *axin_0 - cen0 ); + dyp = ( *axin_1 - cen1 ); + + cr2 = disco*( dxp*dxp + dyp*dyp ); + a = ( 2.0*cr2 + 1.0 )/( 3.0*cr2 + 1.0 ); + cr2a2 = cr2*a*a; + f = ( 2.0*cr2a2*a + 1.0 )/( 3.0*cr2a2 + 1.0 ); + + dx = dxp*f; + dy = dyp*f; + +/* The above approximate inverse is taken from SLA_UNPCD. If more accuracy +c is needed, the following code can be uncommented to iterate to a better +c solution. +c +c fl = 1.0 + disco*( dx*dx + dy*dy ); +c dx = dxp/fl; +c dy = dyp/fl; +c +c df = fabs( fl ); +c while( df > fabs( fl*1.0E-6 ) ){ +c f = 1.0 + disco*( dx*dx + dy*dy ); +c df = fabs( f - fl ); +c fl = f; +c +c dx = dxp/f; +c dy = dyp/f; +c } +*/ + *(axout_0++) = dx + cen0; + *(axout_1++) = dy + cen1; + + } else { + *(axout_0++) = AST__BAD; + *(axout_1++) = AST__BAD; + } + axin_0++; + axin_1++; + } + + } + + } + +/* Return a pointer to the output PointSet. */ + return result; +} + +static void PcdZoom( AstMapping **maps, int *inverts, int ipc, int *status ){ +/* +* Name: +* PcdZoom + +* Purpose: +* Swap a PcdMap and a ZoomMap. + +* Type: +* Private function. + +* Synopsis: +* #include "pcdmap.h" +* void PcdZoom( AstMapping **maps, int *inverts, int ipc, int *status ) + +* Class Membership: +* PcdMap member function + +* Description: +* A list of two Mappings is supplied containing a PcdMap and a +* ZoomMap. These Mappings are annulled, and replaced with +* another pair of Mappings consisting of a PcdMap and a ZoomMap +* in the opposite order. These Mappings are chosen so that their +* combined effect is the same as the original pair of Mappings. + +* Parameters: +* maps +* A pointer to an array of two Mapping pointers. +* inverts +* A pointer to an array of two invert flags. +* ipc +* The index within "maps" of the PcdMap. +* status +* Pointer to the inherited status variable. + +*/ + +/* Local Variables: */ + AstPcdMap *pm2; /* Pointer to the returned PcdMap */ + AstPcdMap *pm; /* Pointer to the supplied PcdMap */ + AstZoomMap *zm2; /* Pointer to the returned ZoomMap */ + AstZoomMap *zm; /* Pointer to the supplied ZoomMap */ + double cen[2]; /* New distortion centre */ + double disc; /* Distortion coeff. for returned PcdMap */ + double disco; /* Distortion coeff. for supplied PcdMap */ + double xcen; /* Axis 0 centre for supplied PcdMap */ + double ycen; /* Axis 1 centre for supplied PcdMap */ + double zoom; /* Zoom factor for supplied ZoomMap */ + int old_pinv; /* Invert value for the supplied PcdMap */ + int old_zinv; /* Invert value for the supplied ZoomMap */ + +/* Check the global error status. */ + if ( !astOK ) return; + +/* Store pointers to the supplied PcdMap and the ZoomMap. */ + pm = (AstPcdMap *) maps[ ipc ]; + zm = (AstZoomMap *) maps[ 1 - ipc ]; + +/* Temporarily set the Invert attribute of the supplied Mappings to the + supplied values. */ + old_pinv = astGetInvert( pm ); + astSetInvert( pm, inverts[ ipc ] ); + + old_zinv = astGetInvert( zm ); + astSetInvert( zm, inverts[ 1 - ipc ] ); + +/* Get the zoom factor from the ZoomMap. */ + zoom = astGetZoom( zm ); + +/* Get the distortion coefficient from the PcdMap. */ + disco = astGetDisco( pm ); + +/* Get the distortion centre from the PcdMap. */ + xcen = astGetPcdCen( pm, 0 ); + ycen = astGetPcdCen( pm, 1 ); + +/* Re-instate the original value of the Invert attributes of the supplied + Mappings. */ + astSetInvert( pm, old_pinv ); + astSetInvert( zm, old_zinv ); + +/* Create the returned ZoomMap. */ + zm2 = astZoomMap( 2, zoom, "", status ); + +/* Find the attributes of the returned PcdMap. If the PCD map is applied + first... */ + if( ipc == 0 ) { + cen[ 0 ] = xcen*zoom; + cen[ 1 ] = ycen*zoom; + disc = disco/(zoom*zoom); + +/* If the PCD map is applied second... */ + } else { + cen[ 0 ] = xcen/zoom; + cen[ 1 ] = ycen/zoom; + disc = disco*zoom*zoom; + } + +/* Create the returned PcdMap. */ + pm2 = astPcdMap( disc, cen, "", status ); + if( inverts[ ipc ] ) astInvert( pm2 ); + +/* Replace the supplied Mappings with the ones created above, swapping the + order. */ + if( astOK ){ + (void) astAnnul( pm ); + (void) astAnnul( zm ); + + maps[ 1 - ipc ] = (AstMapping *) pm2; + inverts[ 1 - ipc ] = inverts[ ipc ]; + + maps[ ipc ] = (AstMapping *) zm2; + inverts[ ipc ] = 0; + + } + +/* Return. */ + return; +} + +static void PcdPerm( AstMapping **maps, int *inverts, int ipc, int *status ){ +/* +* Name: +* PcdPerm + +* Purpose: +* Swap a PcdMap and a PermMap. + +* Type: +* Private function. + +* Synopsis: +* #include "pcdmap.h" +* void PcdPerm( AstMapping **maps, int *inverts, int ipc, int *status ) + +* Class Membership: +* PcdMap member function + +* Description: +* A list of two Mappings is supplied containing a PcdMap and a +* PermMap. These Mappings are annulled, and replaced with +* another pair of Mappings consisting of a PcdMap and a PermMap +* in the opposite order. These Mappings are chosen so that their +* combined effect is the same as the original pair of Mappings. + +* Parameters: +* maps +* A pointer to an array of two Mapping pointers. +* inverts +* A pointer to an array of two invert flags. +* ipc +* The index within "maps" of the PcdMap. +* status +* Pointer to the inherited status variable. + +* Notes: +* - It should have been checked previously that the PermMap simply +* swaps axes 0 and 1. This is the only sort of PermMap which can be +* used here. + +*/ + + AstPermMap *rm; /* Pointer to the supplied PermMap */ + AstPermMap *rm2; /* Pointer to the returned PermMap */ + AstPcdMap *pm; /* Pointer to the supplied PcdMap */ + AstPcdMap *pm2; /* Pointer to the returned PcdMap */ + double cen[2]; /* Centre for new PcdMap */ + double disco; /* Distortion coeff. for supplied PcdMap */ + double xcen; /* Axis 0 centre for supplied PcdMap */ + double ycen; /* Axis 1 centre for supplied PcdMap */ + int old_rinv; /* Invert value for the supplied PermMap */ + int old_pinv; /* Invert value for the supplied PcdMap */ + +/* Check the global error status. */ + if ( !astOK ) return; + +/* Store pointers to the supplied PcdMap and the PermMap. */ + pm = (AstPcdMap *) maps[ ipc ]; + rm = (AstPermMap *) maps[ 1 - ipc ]; + +/* Temporarily set the Invert attribute of the supplied Mappings to the + supplied values. */ + old_pinv = astGetInvert( pm ); + astSetInvert( pm, inverts[ ipc ] ); + + old_rinv = astGetInvert( rm ); + astSetInvert( rm, inverts[ 1 - ipc ] ); + +/* Get the distortion coefficient from the PcdMap. */ + disco = astGetDisco( pm ); + +/* Get the distortion centre from the PcdMap. */ + xcen = astGetPcdCen( pm, 0 ); + ycen = astGetPcdCen( pm, 1 ); + +/* Re-instate the original value of the Invert attributes of the supplied + Mappings. */ + astSetInvert( pm, old_pinv ); + astSetInvert( rm, old_rinv ); + +/* Create the returned PermMap (unchanged). */ + rm2 = astClone( rm ); + +/* Create the returned PcdMap. */ + cen[ 0 ] = ycen; + cen[ 1 ] = xcen; + pm2 = astPcdMap( disco, cen, "", status ); + if( inverts[ ipc ] ) astInvert( pm2 ); + +/* Replace the supplied Mappings with the ones created above, swapping the + order. */ + if( astOK ){ + (void) astAnnul( pm ); + (void) astAnnul( rm ); + + old_pinv = inverts[ ipc ]; + + maps[ ipc ] = (AstMapping *) rm2; + inverts[ ipc ] = inverts[ 1 - ipc ]; + + maps[ 1 - ipc ] = (AstMapping *) pm2; + inverts[ 1 - ipc ] = old_pinv; + } + +/* Return. */ + return; +} + +/* 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). */ +/* +*att++ +* Name: +* Disco + +* Purpose: +* PcdMap pincushion/barrel distortion coefficient. + +* Type: +* Public attribute. + +* Synopsis: +* Double precision. + +* Description: +* This attribute specifies the pincushion/barrel distortion coefficient +* used by a PcdMap. This coefficient is set when the PcdMap is created, +* but may later be modified. If the attribute is cleared, its default +* value is zero, which gives no distortion. For pincushion distortion, +* the value should be positive. For barrel distortion, it should be +* negative. +* +* Note that the forward transformation of a PcdMap applies the +* distortion specified by this attribute and the inverse +* transformation removes this distortion. If the PcdMap is inverted +c (e.g. using astInvert), then the forward transformation will +f (e.g. using AST_INVERT), then the forward transformation will +* remove the distortion and the inverse transformation will apply +* it. The distortion itself will still be given by the same value of +* Disco. +* +* Note, the value of this attribute may changed only if the PcdMap +* has no more than one reference. That is, an error is reported if the +* PcdMap has been cloned, either by including it within another object +* such as a CmpMap or FrameSet or by calling the +c astClone +f AST_CLONE +* function. + +* Applicability: +* PcdMap +* All PcdMaps have this attribute. + +*att-- +*/ +/* This ia a double value with a value of AST__BAD when undefined but + yielding a default of 0.0. */ +astMAKE_CLEAR1(PcdMap,Disco,disco,AST__BAD) +astMAKE_GET(PcdMap,Disco,double,0.0,( ( this->disco == AST__BAD ) ? + 0.0 : this->disco )) +astMAKE_SET1(PcdMap,Disco,double,disco,value) +astMAKE_TEST(PcdMap,Disco,( this->disco != AST__BAD )) + + +/* +*att++ +* Name: +* PcdCen(axis) + +* Purpose: +* Centre coordinates of pincushion/barrel distortion. + +* Type: +* Public attribute. + +* Synopsis: +* Floating point. + +* Description: +* This attribute specifies the centre of the pincushion/barrel +* distortion implemented by a PcdMap. It takes a separate value for +* each axis of the PcdMap so that, for instance, the settings +* "PcdCen(1)=345.0,PcdCen(2)=-104.4" specify that the pincushion +* distortion is centred at positions of 345.0 and -104.4 on axes 1 and 2 +* respectively. This attribute is set when a PcdMap is created, but may +* later be modified. If the attribute is cleared, the default value for +* both axes is zero. +* +* Note, the value of this attribute may changed only if the PcdMap +* has no more than one reference. That is, an error is reported if the +* PcdMap has been cloned, either by including it within another object +* such as a CmpMap or FrameSet or by calling the +c astClone +f AST_CLONE +* function. + +* Applicability: +* PcdMap +* All PcdMaps have this attribute. + +* Notes: +* - If no axis is specified, (e.g. "PcdCen" instead of +* "PcdCen(2)"), then a "set" or "clear" operation will affect +* the attribute value of both axes, while a "get" or "test" +* operation will use just the PcdCen(1) value. +*att-- +*/ +/* The centre of the distortion. AST__BAD is stored if no value has been + supplied, resulting in default values of zero being used. */ +MAKE_CLEAR(PcdCen,pcdcen,AST__BAD,2) +MAKE_SET(PcdCen,double,pcdcen,value,2) +MAKE_TEST(PcdCen,( this->pcdcen[axis] != AST__BAD ),2) +MAKE_GET(PcdCen,double,0.0,(( this->pcdcen[axis] == AST__BAD ) ? + 0.0 : this->pcdcen[axis] ),2) + +/* Copy constructor. */ +/* ----------------- */ +/* No copy constructor is needed, as a byte-by-byte copy suffices. */ + +/* Destructor. */ +/* ----------- */ +/* No destructor is needed as no memory, etc. needs freeing. */ + +/* Dump function. */ +/* -------------- */ +static void Dump( AstObject *this_object, AstChannel *channel, int *status ) { +/* +* Name: +* Dump + +* Purpose: +* Dump function for PcdMap 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 PcdMap class to an output Channel. + +* Parameters: +* this +* Pointer to the PcdMap 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 Variables: */ + AstPcdMap *this; /* Pointer to the PcdMap structure */ + double dval; /* Attribute value */ + int set; /* Is a value set? */ + +/* Check the global error status. */ + if ( !astOK ) return; + +/* Obtain a pointer to the PcdMap structure. */ + this = (AstPcdMap *) this_object; + +/* Write out values representing the instance variables for the + PcdMap 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. */ + +/* PcdCen(0). */ +/* ---------- */ + set = TestPcdCen( this, 0, status ); + dval = set ? GetPcdCen( this, 0, status ) : astGetPcdCen( this, 0 ); + astWriteDouble( channel, "PcdCn0", set, 1, dval, "Distortion centre on first axis" ); + +/* PcdCen(1). */ +/* ---------- */ + set = TestPcdCen( this, 1, status ); + dval = set ? GetPcdCen( this, 1, status ) : astGetPcdCen( this, 1 ); + astWriteDouble( channel, "PcdCn1", set, 1, dval, "Distortion centre on second axis" ); + +/* Disco. */ +/* ------ */ + set = TestDisco( this, status ); + dval = set ? GetDisco( this, status ) : astGetDisco( this ); + astWriteDouble( channel, "Disco", set, 1, dval, "Distortion coefficient" ); + +} + +/* Standard class functions. */ +/* ========================= */ +/* Implement the astIsAPcdMap and astCheckPcdMap functions using the macros + defined for this purpose in the "object.h" header file. */ +astMAKE_ISA(PcdMap,Mapping) +astMAKE_CHECK(PcdMap) + +AstPcdMap *astPcdMap_( double disco, const double pcdcen[2], + const char *options, int *status, ...) { +/* +*++ +* Name: +c astPcdMap +f AST_PCDMAP + +* Purpose: +* Create a PcdMap. + +* Type: +* Public function. + +* Synopsis: +c #include "pcdmap.h" +c AstPcdMap *astPcdMap( double disco, const double pcdcen[2], +c const char *options, ... ) +f RESULT = AST_PCDMAP( DISCO, PCDCEN, OPTIONS, STATUS ) + +* Class Membership: +* PcdMap constructor. + +* Description: +* This function creates a new PcdMap and optionally initialises its +* attributes. +* +* A PcdMap is a non-linear Mapping which transforms 2-dimensional +* positions to correct for the radial distortion introduced by some +* cameras and telescopes. This can take the form either of pincushion +* or barrel distortion, and is characterized by a single distortion +* coefficient. +* +* A PcdMap is specified by giving this distortion coefficient and the +* coordinates of the centre of the radial distortion. The forward +* transformation of a PcdMap applies the distortion: +* +* RD = R * ( 1 + C * R * R ) +* +* where R is the undistorted radial distance from the distortion +* centre (specified by attribute PcdCen), RD is the radial distance +* from the same centre in the presence of distortion, and C is the +* distortion coefficient (given by attribute Disco). +* +* The inverse transformation of a PcdMap removes the distortion +* produced by the forward transformation. The expression used to derive +* R from RD is an approximate inverse of the expression above, obtained +* from two iterations of the Newton-Raphson method. The mismatch between +* the forward and inverse expressions is negligible for astrometric +* applications (to reach 1 milliarcsec at the edge of the Anglo-Australian +* Telescope triplet or a Schmidt field would require field diameters of +* 2.4 and 42 degrees respectively). +* +c If a PcdMap is inverted (e.g. using astInvert) then the roles of the +f If a PcdMap is inverted (e.g. using AST_INVERT) then the roles of the +* forward and inverse transformations are reversed; the forward +* transformation will remove the distortion, and the inverse +* transformation will apply it. + +* Parameters: +c disco +f DISCO = DOUBLE PRECISION (Given) +* The distortion coefficient. Negative values give barrel +* distortion, positive values give pincushion distortion, and +* zero gives no distortion. +c pcdcen +f PCDCEN( 2 ) = DOUBLE PRECISION (Given) +c A 2-element array containing the coordinates of the centre of the +f An array containing the coordinates of the centre of the +* distortion. +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 PcdMap. 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 PcdMap. 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 astPcdMap() +f AST_PCDMAP = INTEGER +* A pointer to the new PcdMap. + +* 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 */ + AstPcdMap *new; /* Pointer to new PcdMap */ + 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 PcdMap, allocating memory and initialising the + virtual function table as well if necessary. */ + new = astInitPcdMap( NULL, sizeof( AstPcdMap ), !class_init, &class_vtab, + "PcdMap", disco, pcdcen ); + +/* 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 PcdMap'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 PcdMap. */ + return new; +} + +AstPcdMap *astPcdMapId_( double disco, const double pcdcen[2], + const char *options, ... ) { +/* +* Name: +* astPcdMapId_ + +* Purpose: +* Create a PcdMap. + +* Type: +* Private function. + +* Synopsis: +* #include "pcdmap.h" +* AstPcdMap *astPcdMapId_( double disco, const double pcdcen[2], +* const char *options, ... ) + +* Class Membership: +* PcdMap constructor. + +* Description: +* This function implements the external (public) interface to the +* astPcdMap constructor function. It returns an ID value (instead +* of a true C pointer) to external users, and must be provided +* because astPcdMap_ 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 astPcdMap_ 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 astPcdMap_. + +* Returned Value: +* The ID value associated with the new PcdMap. +*/ + +/* Local Variables: */ + astDECLARE_GLOBALS /* Pointer to thread-specific global data */ + AstPcdMap *new; /* Pointer to new PcdMap */ + 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 PcdMap, allocating memory and initialising the + virtual function table as well if necessary. */ + new = astInitPcdMap( NULL, sizeof( AstPcdMap ), !class_init, &class_vtab, + "PcdMap", disco, pcdcen ); + +/* 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 PcdMap'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 PcdMap. */ + return astMakeId( new ); +} + +AstPcdMap *astInitPcdMap_( void *mem, size_t size, int init, + AstPcdMapVtab *vtab, const char *name, + double disco, const double pcdcen[2], int *status ){ +/* +*+ +* Name: +* astInitPcdMap + +* Purpose: +* Initialise a PcdMap. + +* Type: +* Protected function. + +* Synopsis: +* #include "pcdmap.h" +* AstPcdMap *astInitPcdMap( void *mem, size_t size, int init, +* AstPcdMapVtab *vtab, const char *name, +* double disco, const double pcdcen[2] ) + +* Class Membership: +* PcdMap initialiser. + +* Description: +* This function is provided for use by class implementations to initialise +* a new PcdMap object. It allocates memory (if necessary) to accommodate +* the PcdMap plus any additional data associated with the derived class. +* It then initialises a PcdMap 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 PcdMap at the start of the memory passed via the +* "vtab" parameter. + +* Parameters: +* mem +* A pointer to the memory in which the PcdMap is to be initialised. +* This must be of sufficient size to accommodate the PcdMap data +* (sizeof(PcdMap)) 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 PcdMap (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 PcdMap +* structure, so a valid value must be supplied even if not required for +* allocating memory. +* init +* A logical flag indicating if the PcdMap'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 PcdMap. +* 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). +* disco +* Distortion coefficient. +* pcdcen +* Distortion centre. + +* Returned Value: +* A pointer to the new PcdMap. + +* 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: */ + AstPcdMap *new; /* Pointer to new PcdMap */ + +/* Check the global status. */ + if ( !astOK ) return NULL; + +/* If necessary, initialise the virtual function table. */ + if ( init ) astInitPcdMapVtab( vtab, name ); + +/* Initialise. */ + new = NULL; + +/* Initialise a Mapping structure (the parent class) as the first component + within the PcdMap structure, allocating memory if necessary. Specify that + the Mapping should be defined in both the forward and inverse directions. */ + new = (AstPcdMap *) astInitMapping( mem, size, 0, + (AstMappingVtab *) vtab, name, + 2, 2, 1, 1 ); + + if ( astOK ) { + +/* Initialise the PcdMap data. */ +/* ---------------------------- */ +/* Store the shift and scale for each axis. */ + new->pcdcen[0] = pcdcen[0]; + new->pcdcen[1] = pcdcen[1]; + new->disco = disco; + +/* If an error occurred, clean up by deleting the new PcdMap. */ + if ( !astOK ) new = astDelete( new ); + } + +/* Return a pointer to the new PcdMap. */ + return new; +} + +AstPcdMap *astLoadPcdMap_( void *mem, size_t size, + AstPcdMapVtab *vtab, const char *name, + AstChannel *channel, int *status ) { +/* +*+ +* Name: +* astLoadPcdMap + +* Purpose: +* Load a PcdMap. + +* Type: +* Protected function. + +* Synopsis: +* #include "pcdmap.h" +* AstPcdMap *astLoadPcdMap( void *mem, size_t size, +* AstPcdMapVtab *vtab, const char *name, +* AstChannel *channel ) + +* Class Membership: +* PcdMap loader. + +* Description: +* This function is provided to load a new PcdMap 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 +* PcdMap 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 PcdMap at the start of the memory +* passed via the "vtab" parameter. + + +* Parameters: +* mem +* A pointer to the memory into which the PcdMap is to be +* loaded. This must be of sufficient size to accommodate the +* PcdMap data (sizeof(PcdMap)) 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 PcdMap (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 PcdMap 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(AstPcdMap) is used instead. +* vtab +* Pointer to the start of the virtual function table to be +* associated with the new PcdMap. If this is NULL, a pointer +* to the (static) virtual function table for the PcdMap 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 "PcdMap" is used instead. + +* Returned Value: +* A pointer to the new PcdMap. + +* 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: */ + astDECLARE_GLOBALS /* Pointer to thread-specific global data */ + AstPcdMap *new; /* Pointer to the new PcdMap */ + +/* Initialise. */ + new = NULL; + +/* Check the global error status. */ + if ( !astOK ) return new; + +/* Get a pointer to the thread specific global data structure. */ + astGET_GLOBALS(channel); + +/* If a NULL virtual function table has been supplied, then this is + the first loader to be invoked for this PcdMap. In this case the + PcdMap belongs to this class, so supply appropriate values to be + passed to the parent class loader (and its parent, etc.). */ + if ( !vtab ) { + size = sizeof( AstPcdMap ); + vtab = &class_vtab; + name = "PcdMap"; + +/* If required, initialise the virtual function table for this class. */ + if ( !class_init ) { + astInitPcdMapVtab( 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 PcdMap. */ + new = astLoadMapping( mem, size, (AstMappingVtab *) 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, "PcdMap" ); + +/* 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. */ + +/* PcdCen(0). */ +/* ---------- */ + new->pcdcen[0] = astReadDouble( channel, "pcdcn0", AST__BAD ); + if ( TestPcdCen( new, 0, status ) ) SetPcdCen( new, 0, new->pcdcen[0], status ); + +/* PcdCen(1). */ +/* ---------- */ + new->pcdcen[1] = astReadDouble( channel, "pcdcn1", AST__BAD ); + if ( TestPcdCen( new, 1, status ) ) SetPcdCen( new, 1, new->pcdcen[1], status ); + +/* Disco. */ +/* ------ */ + new->disco = astReadDouble( channel, "disco", AST__BAD ); + if ( TestDisco( new, status ) ) SetDisco( new, new->disco, status ); + +/* If an error occurred, clean up by deleting the new PcdMap. */ + if ( !astOK ) new = astDelete( new ); + } + +/* Return the new PcdMap pointer. */ + return new; +} + +/* 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. */ + + + + + |