I was thinking to a way for the transition: we could:
- change the t_pdinstance pd_s_* fields to pointers (and adapt the s_*
replacement macros accordingly),
- export "hidden" globals s_*
- initialize pd_maininstance pd_s_* fields to the global versions.
Yes, this would work. Of course, it would be an ABI break for
multi-instance libpd, but I think it would be justified. I guess libpd
users rarely rely on pre-build externals, and even if they do, I think
it's ok to ask them to recompile.
We should probably also put the global s_* symbols in a deprecation
macro that tells external authors to use gensym() instead.
Christof
On 04.04.2022 13:55, Antoine Rousseau wrote:
I very much agree that in the future Pd (and externals) could be
always compiled with PDINSTANCE.
I was thinking to a way for the transition: we could:
- change the t_pdinstance pd_s_* fields to pointers (and adapt the s_*
replacement macros accordingly),
- export "hidden" globals s_*
- initialize pd_maininstance pd_s_* fields to the global versions.
CURRENT:
/* m_pd.h */
struct _pdinstance
{
t_symbol pd_s_float;
}
#define s_float (pd_this->pd_s_float)
/* m_class.c */
t_pdinstance *pdinstance_init(t_pdinstance *x)
{
dogensym("float", &x->pd_s_float, x);
}
PROPOSAL:
/* m_pd.h */
struct _pdinstance
{
t_symbol *pd_s_float;
}
#define s_float (*(pd_this->pd_s_float))
/* m_class.c */
#undef s_float
t_symbol s_float;
t_pdinstance *pdinstance_init(t_pdinstance *x)
{
if(x != &pd_maininstance) x->pd_s_float = gensym("float");
else {
dogensym("float", &s_float, x);
x->pd_s_float = &s_float;
}
What do you think?
I've tried this (in libpd context) almost successfully, but I've
encountered a problem: the s_float as seen from an app linked to libpd
seems to be uninitialized.
I've tried something simpler:
/* m_class.c */
float myfloat = 10.0;
t_pdinstance *pdinstance_init(t_pdinstance *x)
{
myfloat = 20.0;
printf("pdinstance_init::myfloat: %f\n", myfloat);
}
/* pdtest.c */
extern float myfloat;
int main()
{
libpd_init();
printf("myfloat: %f\n", myfloat);
}
cc -I../../../libpd_wrapper -I../../../pure-data/src -O3 -c -o
pdtest.o pdtest.c
gcc -o pdtest pdtest.o ../../../libs/libpd.so
$ pdtest
pdinstance_init::myfloat: 20.00000
myfloat: 10.00000
Do you know why pdtest doesn't see the updated value?
Le mer. 30 mars 2022 à 23:51, Christof Ressi <i...@christofressi.com>
a écrit :
AFAICT, the main issue is that multi-instance Pd misses symbols for
certain global variables, most notably s_float, s_symbol, s_bang,
etc.
The problem is that these are really exported global structs. If they
were *pointers*, we could simply make them point to the corresponding
field in the main Pd instance. But in this case I don't really see a
solution...
On 30.03.2022 18:07, IOhannes m zmoelnig wrote:
>
> On 3/30/22 17:45, Dan Wilcox wrote:
>> I lean much more on the side that PDINSTANCE is a low-level, per
>> project compile option and not general-purpose. If you are using
>> libpd, then your environment is a bit more custom anyway.
>
> i wonder what the penalty would be to turn on PDINSTANCE on Pd?
>
>
> obviously a problem with externals, but maybe we can come up
with some
> clever hack (under the assumption, that Pd (the app) only runs a
> single instance, even if compiled with multi-instance support)
to use
> legacy externals - if that is even possible.
>
> apart from that?
>
> fgadrms
> IOhannes
>
> _______________________________________________
> Pd-dev mailing list
> Pd-dev@lists.iem.at
> https://lists.puredata.info/listinfo/pd-dev
_______________________________________________
Pd-dev mailing list
Pd-dev@lists.iem.at
https://lists.puredata.info/listinfo/pd-dev
_______________________________________________
Pd-dev mailing list
Pd-dev@lists.iem.at
https://lists.puredata.info/listinfo/pd-dev
_______________________________________________
Pd-dev mailing list
Pd-dev@lists.iem.at
https://lists.puredata.info/listinfo/pd-dev
