Filter to modify choices (includes whether the choice has exceeded its limit).
Apply to all fields on all forms.
add_filter( 'gpi_pre_render_choice', 'my_custom_function' );
Apply to all fields on a specific form.
add_filter( 'gpi_pre_render_choice_FORMID', 'my_custom_function' );
Apply to a specific field on a specific form.
add_filter( 'gpi_pre_render_choice_FORMID_FIELDID', 'my_custom_function' );
The current choice.
Whether the current choice has exceeded its inventory limit.
Current field object.
Counts of claimed inventory for each choice.
This filter is available since Gravity Forms Inventory 1.0-beta-1.0.