param_types.h

#ifndef PARAM_TYPES_H
#define PARAM_TYPES_H
#include "expr_types.h"
#define P_CREATE 1
#define P_NONE 0

#define P_TYPE_BOOL 0
#define P_TYPE_INT 1
#define P_TYPE_DOUBLE 2

#define P_FLAG_NONE 0
#define P_FLAG_READONLY 1
#define P_FLAG_USERDEF (1 << 1)
#define P_FLAG_QVAR (1 << 2)
#define P_FLAG_TVAR (1 << 3)
#define P_FLAG_ALWAYS_MATRIX (1 << 4)
#define P_FLAG_DONT_FREE_MATRIX (1 << 5)
#define P_FLAG_PER_PIXEL (1 << 6)
#define P_FLAG_PER_POINT (1 << 7)

typedef union VALUE_T {
  int bool_val;
  int int_val;
  double double_val;    
} value_t;

/* Parameter Type */
typedef struct PARAM_T {
  char name[MAX_TOKEN_SIZE]; /* name of the parameter, not necessary but useful neverthless */
  short int type; /* parameter number type (int, bool, or double) */    
  short int flags; /* read, write, user defined, etc */ 
  short int matrix_flag; /* for optimization purposes */
  void * engine_val; /* pointer to the engine variable */
  void * matrix; /* per pixel / per point matrix for this variable */
  value_t default_init_val; /* a default initial condition value */
  value_t upper_bound; /* this parameter's upper bound */
  value_t lower_bound; /* this parameter's lower bound */
} param_t;
#endif

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