[pdf-devel] Re: GNU PDF functions

[jemarch]

   My old implementation uses a  pdf_func_t type.
   A call to pdf_eval_func( pdf_func_t, pdf_real_t in[], pdf_real_t out[])
   can evaluate any pdf function in a uniform way.

   Strangely enough, this highly specialized type seems to belong to the 
   base layer. Its internals reflect the description in section 3.9, with 
   emphasis on function application only. It is not a pdf object, and it 
   does not use pdf objects. The object layer would provide
   a conversion constructor from  pdf_obj_t to pdf_func_t.
   The base layer would handle cleanup and deallocation.

   What's your opinion?

Given that interface and given that all the configuration parameters
for any type of function can be expressed using base layer data types,
I agree in that we can implement pdf_func_t in the base layer. There
is a pdf_func_new_* function for each type of function, isnt it?

So the question now is, what module in the base layer is the right one
to contain the implementation of pdf_func? May we define a new module
for that?

In any case I think that the interpolation routines definite belong
to the pdf-fp module: other parts of the library may find these
functions useful.