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#ifndef _ZL_PD_H_
#define _ZL_PD_H_
#include "m_pd.h"
#include "zl/zl.h"
/*
To bridge 2 programming systems, the real hurdle is in
impedance-matching the data types and memory model.
In ZL this is done by keeping a very simple basic data type: C
variable argument lists where tags are reprented using
typedef const char *zl_tag;
A. List representation
----------------------
There are essentially 2 kinds of list in C that are easy to use inside
the language:
- Static data initializers. This requires a union (optionally tagged)
so has some syntactic overhead. Works for global and local
variables.
- Variable argument lists. This is a feature supported by the C
standard and is very convenient to use as there is no notational
overhead.
Often converted data is short-lived, allowing data conversion to be
implemented with nested C calls. Both are able to side-step malloc()
when they are combined with some kind of callback mechanism.
B. List tagging
---------------
Using const char * as a tag type allows 2 things to be married in a
very elegant way:
- Pointer-based comparison in C without memory allocation overhead
(all string memory allocation is static).
- Easy conversion to run-time interned symbols (hashed strings) for
dynamic languages.
*/
/* To further limit complexity, for interfaacing with Pd, ZL uses
tagged double lists, easy to convert to pd format. */
static inline void outlet_zl_float_list(t_outlet *o, int nb_double_args, zl_tag tag, va_list args) {
t_atom pd_list[nb_double_args];
int i;
for (i = 0; i< nb_double_args; i++) {
SETFLOAT(&pd_list[i], va_arg(args, double));
}
outlet_anything(o, gensym(tag), nb_double_args, pd_list);
}
#endif
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