I have an object that wants to query its type as part of a custom
attribute set method. I have tried to find sample code doing this in
the SDK projects without success.

Here’s what I want to do in pseudo-code, starting with a stripped
down Jitter initialization function:

===================
t_jit_err InitializeJitterObject(void)
{
jit_class_new(…);
jit_object_new(…);
jit_class_addadomrnment(…);
jit_class_addmethod(…); // repeat for all methods

// AddAttributes — This is the interesting part
attr = jit_object_new(_jit_sym_jit_attr_offset_array,
“loc”, _jit_sym_float64,
JIT_MATRIX_MAX_PLANECOUNT, kAttrRWFlags,
(method) NIL,
(method) ExpoSetLoc, // SEE BELOW
calcoffset(jcobExpo, planeCount),
calcoffset(jcobExpo, loc)
);

// Finish off
jit_class_register(gExpoJitClass);
return JIT_ERR_NONE;
}

…

static void ExpoSetLoc(
objExpo* me, // This is the Jitter object
void* attr, // Unused
long iArgC,
Atom iArgVec[])

{
Symbol typeSym = GetObjectType(me); // HOW DO I DO THIS??

if (typeSym == _jit_sym_char) {
// Clip input values in iArgVec to 0 .. 256 and store
}
else if (typeSym == _jit_sym_long) {
// Clip input values to kLongMin .. kLongMax and store
// A little anal retentive, but just to be safe
}
// otherwise just store without clipping

}

===================

Is this reasonable to want to do? If so, how?

It seems likely that the pseudo-function GetObjectType() will do
something like

jit_object_method(me, _jit_sym_gettype, …);

but I can’t find an example of how this would work.

Thanks,
Peter

————– http://www.bek.no/~pcastine/Litter/ ————-
Peter Castine +–> Litter Power & Litter Bundle for Jitter

iCE: Sequencing, Recording & |home | chez nous|
Interface Building for |bei uns | i nostri|
Max/MSP Extremely cool http://www.castine.de

http://www.dspaudio.com/

t_symbol *jit_object_classname(void *x);

Hopefully this helps you out. Otherwise, I need some clarification.
best,
wes

> This is probably for Jeremy or Joshua.
>
> jit_object_method(me, _jit_sym_gettype, …);

t_symbol *mytype = jit_attr_getsym(me,_jit_sym_type);

Or if you really prefer, here’s how you would accomplish with
jit_object_method:

t_atom *av=NULL;
long ac=0;
t_symbol *mytype;

jit_object_method(me,_jit_sym_gettype,&ac,&av);

if (ac&&av) {
mytype = jit_atom_getsymbol(av);
jit_freebytes(av);
}

Lastly, we typically look at this with matrices using the standard
getinfo with the matrixinfo struct.

-Joshua

That’s pretty easy. Thanks.

> Or if you really prefer, here’s how you would accomplish with
> jit_object_method:
[schnipp]

Useful to know.

> Lastly, we typically look at this with matrices using the standard
> getinfo with the matrixinfo struct.

You mean a t_jit_matrix_info? That’s the way I do it in my
matrix_calc method. But I’m not sure how to get a pointer to a
t_jit_matrix_info in the situation I was describing, namely inside a
custom set-attribute method.

It might actually be better to clip the attribute values inside the
matrix_calc method anyway. I’m not sure.

–

Thanks also to Wes. The issue is whether my Jitter object is dealing
with a char/long/float32/float64 matrix (ie “type” as in the
attribute “type” that shows up in the “messages for

– P.

————– http://www.bek.no/~pcastine/Litter/ ————-
Peter Castine +–> Litter Power & Litter Bundle for Jitter

iCE: Sequencing, Recording & |home | chez nous|
Interface Building for |bei uns | i nostri|
Max/MSP Extremely cool http://www.castine.de

http://www.dspaudio.com/

Here’s some untested code for getting the type on the fly from an
arbitrary point in your code, given the Jitter object pointer.

void *mop = jit_class_adornment_get(_myobject_class, _jit_sym_jit_mop);
void *o = jit_object_method(mop, _jit_sym_getoutput, 1);
void *m = jit_object_method(o, _jit_sym_getmatrix);
t_jit_matrix_info info;

jit_object_method(m, _jit_sym_getinfo, &info);
t_symbol *type = info.type;

Am 18.06.2006 um 07:56 schrieb Peter Castine:

> It might actually be better to clip the attribute values inside the
> matrix_calc method anyway. I’m not sure.

That was what was concerning me, although I wasn’t able to formulate
the concern succinctly last night. I was trying to shave a
performance improvement by clipping at set-attribute time (happens
typically less often than process-matrix time), but that’s a false
economy.

> Here’s some untested code for getting the type on the fly from an
> arbitrary point in your code, given the Jitter object pointer.

The snippet gets filed under “Very Good to Know”. Cool, vielen Dank!

– P.

PS: You’re up and about early on a Sunday morning!

————– http://www.bek.no/~pcastine/Litter/ ————-
Peter Castine +–> Litter Power & Litter Bundle for Jitter

iCE: Sequencing, Recording & |home | chez nous|
Interface Building for |bei uns | i nostri|
Max/MSP Extremely cool http://www.castine.de

http://www.dspaudio.com/