jpruvot wrote:

> typedef double dReal;
> typedef dReal dVector3[4];
> typedef dReal dVector4[4];
>
> struct dxGeom;        /* geometry (collision object) */
> typedef struct dxGeom *dGeomID;
> typedef struct dContactGeom {
> dVector3 pos;
> dVector3 normal;
> dReal depth;
> dGeomID g1,g2;
> } dContactGeom; 

create a class "DContactGeom" with the field definition:

fields
^ #(#(#pos 'DVector3')
    #(#normal 'DVector3')
    #(#length 'double')
    #(#g1 'DGeomID')
    #(#g2 'DGeomID'))

create a class "DVector3" and a class "DVector4" (what's the difference
there?!) with the field definition:

fields
^ #(#(#element1 'double')
    #(#element2 'double')
    #(#element3 'double')
    #(#element4 'double'))

you could also say (- as i learned recently! ;-) -)

fields
^ #(#(#data 'double' 32))

(which will create a structure that is 32byte = 4*double sized, but
unfortunately data only refers to the first double - so if you want
to access the rest, you'd have to take use of "#getHandle")

create a class "dGeomID" with the field definition:
fields
^ #(#(#geometry 'dxGeom*'))


you'll have to declare a class "dxGeom", too - i didn't find one in your
message... (only a forward declaration or so...)

> typedef struct dGeomClass {
> int bytes;
> dGetColliderFnFn *collider;
> dGetAABBFn *aabb;
> dAABBTestFn *aabb_test;
> dGeomDtorFn *dtor;
> } dGeomClass; 

create a class "DGeomClass" with the field definition:

fields
^ #(#(#bytes 'long')
    #(#collider 'DGetColliderFnFn*')
    #(#aabb 'DBetAABBFn*')
    #(#aabb_test 'DAABBTestFn*')
    #(#dtor 'DGeomDtorFn'))


hope that helps...

however - it seems to me that you are handling with function pointers.
probably by means of callback-functions. i'm not sure if there's any way
to define those functions in squeak and pass a handle on through ffi -
but i think, there is no such thing...

cheers,
ivo