Solved:
(defmd gnc-point () (x (c-in 0)) (y (c-in 0)) (z (c-in 0)) (foreign-ptr (c-in (fgn-alloc 'glInt 3 :gnc-point))))
(defobserver x ((self gnc-point)) (with-integrity (:change self) (let ((ptr (^foreign-ptr))) (if ptr (setf (eltgli ptr 0) (^x)) (error "OBSERVER X OF ~S: FOREIGN-PTR is NIL (Foreign memory not available)" self)))))
(defobserver y ((self gnc-point)) (with-integrity (:change self) (let ((ptr (^foreign-ptr))) (if ptr (setf (eltgli ptr 1) (^y)) (error "OBSERVER Y OF ~S: FOREIGN-PTR is NIL (Foreign memory not available)" self)))))
(defobserver z ((self gnc-point)) (with-integrity (:change self) (let ((ptr (^foreign-ptr))) (if ptr (setf (eltgli ptr 2) (^z)) (error "OBSERVER Z OF ~S: FOREIGN-PTR is NIL (Foreign memory not available)" self)))))
... A bit more complex but works ;-)
Frank
Am 29.08.2007 um 21:50 schrieb Frank Goenninger:
- PGP Signed: 08/29/07 at 21:50:08
Correct problem case:
I defined the foreign-ptr cell as lazy (as :until-asked) for a reason ... ->
0> 7612 calculating cell ~a appears in call stack: ~a dirty=0/ foreign-ptr/gnc-point0] dirty=0/foreign-ptr/gnc-point0] (dirty=0/foreign-ptr/gnc-point0])
... landing in a (break) ...
Ok. So I am basically looking for an idiom on how to avoid the circularity. I sense there is a simple solution but ...
Oh my. It's been a long day ;-)
Frank
Am 29.08.2007 um 21:35 schrieb Frank Goenninger:
Old Signed: 08/29/07 at 21:35:14
Hi Kenny (and all on the list):
I have a simple defmd:
(defmd gnc-point () (x (c-in 0)) (y (c-in 0)) (z (c-in 0)) (foreign-ptr (c_? (let ((ptr (or (^foreign-ptr) (fgn-alloc 'glInt 3 :gnc-point)))) (when ptr (setf (eltgli ptr 0) (^x)) (setf (eltgli ptr 1) (^y)) (setf (eltgli ptr 2) (^z))) ptr))))
This is a model for a point ( x | y | z ) and a foreign object pointer. The pointer shall be set to a an FFI memory pointer (via CFFI) when the instance is created. Also, the elements of the memory array (which is 3 glInt, this being three OpenGL Integers) shall be updated when any of the coordinates x y z is changed...
I get x, y, and z updated but the foreign-ptr remains NIL ... What am I doing wrong ???
Thx!
Frank
- Frank Goenningerfrgo@mac.com
- 0xED320F02:0x05AE0907
cells-devel site list cells-devel@common-lisp.net http://common-lisp.net/mailman/listinfo/cells-devel
Old Signed: 08/29/07 at 21:35:14
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- Frank Goenningerfrgo@mac.com
- 0xED320F02:0x05AE0907
- Frank Goenningerfrgo@mac.com
- 0xED320F02:0x05AE0907
cells-devel site list cells-devel@common-lisp.net http://common-lisp.net/mailman/listinfo/cells-devel
- PGP Signed: 08/29/07 at 21:50:08
- text/plain body
- Frank Goenningerfrgo@mac.com
- 0xED320F02:0x05AE0907