[cells-devel] Cello: 'find-view-under: Semantics ?

[Frank Goenninger]

Am 24.07.2009 um 17:48 schrieb Kenneth Tilton:

> Frank Goenninger wrote:
>> Hi again -
>> thanks again for the fast response on my last request - hoping for   
>> another fast one here ;-)
>> So, Cello (the original one) has this function:
>> (defun find-ix-under (self os-pos &key (test #'true))
>>   (when (and (not (typep self 'tool-tip)) ;; <g>
>>           (visible self)
>>           (not (collapsed self)))
>>     (trc nil "find-ix-under" self os-pos (screen-box self))
>>     (let ((inself (point-in-box os-pos (screen-box self))))
>>       (or (when (or inself (not (clipped self)))
>>             (trc nil "inside self sbox" self os-pos (screen-box  
>> self))
>>             (dolistreversed (k (or (render-order self)(kids   
>> self))) ;; overlap goes to last kid displayed
>>               (unless (typep k 'window)
>>                 (trc nil "fixunder kid!!!!!!!!" k)
>>                 (bwhen (ix (find-ix-under k os-pos :test test))
>>                   (return-from find-ix-under ix)))))
>>           (when (and inself
>>                      (funcall test self)
>>                      (not (ix-click-transparent self)))
>>             (trc nil self os-pos (screen-box self))
>>             self)))))
>> which is used as follows:
>> (defmd mouse-view-tracker ()
>>   (mouse-view :initarg :mouse-view :accessor mouse-view
>>     :initform (c? (let ((pos (mouse-pos .og.)))
>>                     (trc nil "mouseview sees pos" .w. pos)
>>                     (when pos
>>                       (eko (nil "ix-togl mouseview >" self)
>>                         (without-c-dependency
>>                             (find-ix-under self pos)))))))
>>   (:documentation "Mixin to have mouse view tracked in a subtree  
>> of  the window, mostly so other GUI layout can depend on
>> the sub-tree layout without creating a cyclic dependency, as would   
>> happen iof the whole window were watched."))
>> (defmd ix-togl (mouse-view-tracker #+not focuser ogl-lit-scene  
>> control  ogl-shared-resource-tender togl ix-view)
>> ...
>> So, the togl widget is a sub-class of mouse-view-tracker. I  
>> understand  this as "show me the control that is currently being  
>> pointed at by the  mouse".
>> Only thing is: When looking at the code for 'find-ix-under I can't  
>> see  how this could possibly work? May I ask for a walk-through of  
>> find-ix- under ?
>
> haha, no!

;-) Hehe - as if I hadn't expected to get a "Joe, you can do this  
yourself" answer... but:

> Please walk me thru what you do not understand.

I actually am still struggling with things like g-box, g-offset, and  
stuff. That's where my problem lies, really, or so it seems...

> The disabled debug statements give you some hints: first I  
> recursively check kids, if that comes up empty I check myself to see  
> if I am under the mouse and want to be the result.

Well, that's just clear - it does work in original Cello. But it  
doesn't in my Remake... Sh*t.

>
> hth, kt
>
> ps. Yes, it works. :) k

I know. I can see it when running original Cello here. Hmpf !

I could help to have a real good IDE with stepping support - which I  
don't have. I miss it rarely, but currently I do !!! AllegroCL sucks  
in this respect on Mac OS X...

Cheers
    Frank

--
   Frank Goenninger

   Cell: 	+49 175 4321058
   E-Mail: 	frgo at me.com