what values are available for the GParamDef args in the query_proc()?
Each entry has three elements: the type, a name string, and a definition string. Both string values are user-definable. The first element must be one of the types defined in the GParamType enumerated type in libgimp/gimpenums.h . The first three entries in the GParamDef array must be of the correct types, in order: PARAM_INT32, PARAM_IMAGE, and PARAM_DRAWABLE. You need all three of these, and might as well just copy them verbatim from an existing plug-in.
