How to get AEGP_EffectRefH within the custom effect?

Question

Hi,
    I want to get the AEGP_EffectRefH of the custom effect applied. This is what I'm trying to do:
In global setup of custom effect:
AEGP_GlobalRefcon globalRef    =    NULL;
const A_char*        pluginName    =    "ADBE Custom Effect";
AEGP_SuiteHandler    suites(in_data->pica_basicP);
suites.UtilitySuite5()->AEGP_RegisterWithAEGP(globalRef, pluginName, &S_Plugin_ID );
After getting the plugin ID, I do this in a function to get the AEGP_EffectRefH:
I call this function when the custom effect is added:
void function()
     AEGP_EffectRefH        effect_refH        =    NULL;
     AEGP_SuiteHandler    suites(in_data->pica_basicP);           
     ERR(suites.PFInterfaceSuite1()->AEGP_GetNewEffectForEffect(S_Plugin_ID, in_data->effect_ref, &effect_refH));
But the effect_refH returned is NULL. AE pops up a dialog saying
After Effects error: internal verification failure, sorry! {child not found in parent}
(29 :: 0)
What am I doing wrong?
Thanks,
Dheeraj

Answer 1

about the reliability of effectRefs:
they are reliable for the duration of one call.
i.e. for the beginning to the end of the render call or updtate_params_ui call.
after that cal has ended, the effectRef is likely to become invalidated.
do an experiment:
get an effect's effectRef, and check it's address in ram.
releast the effetcRef and get another effectRef for a DIFFERENT effect.
check it's adress and you'll be amazed that it has the same address as the first.
why is that?
because it doesn't point to the address of that effect in ram.
it's an internal id that allows AE to operate on the effect for you.
so that same effectRef you have, might point to a different effect or to nothing at all, once AE decides that the effectRef you acquired is no longer in use.
AE will decide that after you release the effetcRef, or that you effect returns from it's call.
so what does all that mean?
it means you should treat effectRefs and a temporary key for accessing an effect, and NOT as a long term means of identifying and effect.
there is no perfect solution for tracking an effect for long spans.
if you want to keep track of an effect outside the scope of one call you have to:
1. get the itemID for the comp it's in
2. get the layerID for the layer it's on
3. get the effect's index on the layer (this is the tricky bit)
the comp's itemID and layerID both last for the lifetime of the project.
they will keep across sessions, even if the project is loaded on a different machine and a different platform.
these only get invalidated if the project is imported into another project.
the index of the effect is the problem bit.
there is no API call for getting an effects index.
you can only tell the index by counting all effects on the layer, until you hit the desired effect.
even then it's hard to tell because you tell what effect you hit by reading it's matchName.
what if you have to copies of the same effect on one layer?
how do you tell them apart?
it's up to you to create a unique identifier.
either a hidden slider holding a random value that's unique to each instance, or change the effect name to something unique (the user might change that without you knowing)
the last problem with the index is that the user might change effects order on that layer, and your effect get no notification of that having happened.
so even if you stored the itemID, layerID and effect index, you still have to make sure it's the correct effect before you do something hasty like access it.
as i said,
there is no perfect long term solution for tracking effects.