

"Bald Eagle" <cre### [at] netscapenet> wrote:
> So, I'm working on some other patterns, and I have some general functions that I
> want to use.
>
> The problem is that those functions are things like derivatives, which are
> functions OF other functions.
>
> Is there a way that I can cleanly and elegantly implement a function declaration
> that will allow me to do this?
>
> Otherwise it seems that I'm going to have to either
> a) write a macro to #undef the f'(x) function and redefine it for every function
> that I want to operate on
>
> and/or
>
> b) wind up defining individual functions for every function I want to take the
> function OF  which leads to the morass of multiple functions that I need to
> keep track of  so I can remember which one I need, avoid copypaste errors, and
> avoid name collisions  I _disdain_.
>
> Because if I need multiple derivatives at render time, then the macro
> workaround is out.
>
>  BE
I'm not sure I completely understand what you are trying to avoid, but here's an
example of a functionmanipulating macro I created that takes a function as a
parameter:
//
// Translate_fn(FN,T)
//
#macro Translate_fn(FN,T)
#local _t = <1,1,1>*T;
#local _tx = _t.x;
#local _ty = _t.y;
#local _tz = _t.z;
function {
FN(x_tx,y_ty,z_tz)
}
#end
// End Translate_fn
//
Usage:
#local _my_function = function(x,y,z) { x*y  z }
#local _my_trans_function = Translate_fn(_my_function, <1,1,1>)
Obviously translation is a lot simpler than taking a derivative, so I may be
missing your point here.
 Chris R.
 Happily rendering since 2014
Post a reply to this message

