[cffi-devel] How do i cast variables

[Martin Simmons]

>>>>> On Tue, 22 Oct 2013 15:48:50 -0700 (PDT), Joeish W said:
> 
> take this for instance 
> 
> CvPoint points[2];
> 
> 
> id like to be able to cast  points[2] to the CvPoint struct  more info here http://docs.opencv.org/modules/core/doc/old_basic_structures.html?highlight=cvpoint#CvPoint
> 
> 
> here is my struct which works for other things
> 
> 
> 
> ;; (cffi:foreign-type-size '(:struct cv-point)) = 8 
> (cffi:defcstruct cv-point 
> (x :int) 
> (y :int)) 
> 
> 
> put in a defparameter you cant just go 
> 
> (defparameter points (cffi:foreign-alloc :int :count 2))
> 
> (defparameter a ((:struct cv-point) points))
> 
> 
> you get an illegal function call error...any help is appreciated

Your example is inconsistent -- in C, your points variable is an array of two
CvPoints, but in Lisp it is an array of two ints.

What are you really trying to do?

I suggest you post the C code that you are trying to convert.  The opencv doc
for CvPoint doesn't use casting or arrays of ints.

__Martin