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World: r3wp

[!REBOL3 GUI]

Oldes
25-Dec-2010
[4793]
I miss the basics... for example it's not easy to display just a 
GOB in current version.
BrianH
25-Dec-2010
[4794]
The term "faceless" is pretty accurate. What I'm worried about is 
that it will fail if the gob doesn't have any face assigned to its 
data field. It would be more robust to do this instead:
faceless?: func [
    {find out, whether a gob is faceless}
    gob [gob!]
][not same? gob select gob/data 'gob]
Oldes
25-Dec-2010
[4795x2]
It would be good to have somethink like GUI/base which could be used 
to make micro guis - as a platform for own guis.
When I was talking about naming, I was thinking how the values are 
named in DATA object.
BrianH
25-Dec-2010
[4797]
The 'data field only refers to a face object in this GUI. It doesn't 
have to refer to a face, or even an object at all. It really is a 
generic data field.
Ladislav
25-Dec-2010
[4798x3]
What I'm worried about is that it will fail if the gob doesn't have 
any face assigned to its data field.

 - surely, Steeve and Brian, it has to be done, if such a situation 
 is expectable. Is it?
(i.e. can we expect some gobs to not refer to any face?)
Of course, there are other situations the code does not expect, like 
e.g. if the gob/data were an integer value, etc
BrianH
25-Dec-2010
[4801x2]
Throw in enough conditions and it becomes faster to just use an ASSERT/type 
[gob/data/gob object!]. Or just use a get-path :gob/data/gob and 
just accept that errors will be triggered if the function is applied 
to inappropriate gobs.
Sorry, ASSERT/type [gob/data/gob gob!]
Steeve
25-Dec-2010
[4803]
I don't want to begin a flamewar, but troubles are poping continously 
out of my mind. 

And I wondering, Wy did they choose to use a face (an objet) as the 
entry point of most of their low level graphic functions instead 
of a gob! (which is more convenient to my minf).

I can not take away the feeling that the faces?  function should 
just be a shortcut for gob/pane.

Maybe I should not expose my impression after having eaten and drunk 
in a good restaurant :-)
BrianH
25-Dec-2010
[4804x2]
The gobs are the low-level entry point. The faces are the high-level 
entry point. There are two entry points.
Most of what makes a face a face is not in the gob; the gob is just 
appearance.
Steeve
25-Dec-2010
[4806]
I have nothing to say against it, but was that a controversy ?
Pekr
25-Dec-2010
[4807]
IIRC gobs were introduced so that we don't necessarily need faces?
BrianH
25-Dec-2010
[4808]
Gobs were introduced so we had something lightweight and low-level 
to implement appearance, without all of the overhead of a full face. 
That is why a face can have many subgobs without necessarily having 
any subfaces.
Steeve
25-Dec-2010
[4809]
yeah I see them like that too. But when a gob need to deal with events, 
it has to be connected with a face.
BrianH
25-Dec-2010
[4810]
Right, because a face has (among other things) behavior, while a 
gob only has appearance and the pane.
Ladislav
25-Dec-2010
[4811]
Throw in enough conditions and it becomes faster to...

 - I do not want to throw in any unnecessary conditions. The condition 
 I used was verifiably necessary, but I do not know whether there 
 is any other.
BrianH
25-Dec-2010
[4812]
Put the path last in the function, or use a get-path, and there won't 
be any code injection possibilities.
Ladislav
25-Dec-2010
[4813]
surprisingly, while :word is faster than word (according to my measurements), 
:word1/word2 is slower than word1/word2, interesting
Steeve
25-Dec-2010
[4814]
how much ?
Ladislav
25-Dec-2010
[4815x2]
not much, but it is surprising anyway (at least for me)
code injection possibilities

 - aha, you think that it might be dangerous if somebody intentionally 
 defined an "unexpected" kind of gob to somehow use that against a 
 security measure?
BrianH
25-Dec-2010
[4817x3]
It might be possible that the GUI will only be used by safe code, 
so it wouldn't need the kind of hardening that the module system 
and mezzanines got. There are other ways to make things safeish, 
in theory. And code injection attacks aren't quite as bad as they 
could be if the security permissions were user-specific. Still, I'm 
in the habit now of looking at code as if I wanted to attack it :)
It would be hard to do a code injection with this code, since SAME? 
takes two arguments so you can't easily inject with a function that 
takes an argument, without causing an error in the call to SAME?. 
The only other way to inject code would need debug permissions. So 
it's not a big deal here.
Another thing to be concerned with is leaking bindings, but that's 
not a problem here (function context).
DideC
28-Dec-2010
[4820x5]
Help please ! What am I doing wrong ?
boxg: make gob! [offset: 20x20 size: 320x320 Draw: [pen red box 10x10 
317x317]]
win: make gob! [text: "Test" size: 500x500]
append win boxg
view win
Last line give :
** Script error: cannot MAKE/TO map! from: none!
** Where: make view

** Near: make map! reduce/no-set opts if no-wait [opts/no-wait: true]...
If I change the last line, I get this error :

view/options win []

** Script error: cannot access event-port in path system/view/event-port/locals/
handlers
** Where: handle-events unless if view
** Near: handle-events [
    name: 'view-default
    priority: 50
   ...
tried on R3-A96 eand R3-a95
Henrik
28-Dec-2010
[4825]
do you get the same in A110?
Pekr
28-Dec-2010
[4826x4]
it seems we are not able to display simple gob anymore?
ah, view/as-is is needed ....
DideC: try to add the following line in front of "view win": 

append system/view/screen-gob win
hehe, what is that? :-)

>> do-events
A mystery GUI event?
DideC
28-Dec-2010
[4830]
A110 : need to dowload it and test...
Henrik
28-Dec-2010
[4831]
that happens when no event handler is found, which a bare GOB would 
not have:

; Obtain face or handler object, do event handling:
		either all [
			obj: event/window/data
			obj: select obj 'handler
		][
			;print ["Do-event" event/type "for:" obj/name]
			event: obj/do-event event
		][
			print "A mystery GUI event?"
			halt
		]
Pekr
28-Dec-2010
[4832]
Couldn't there be some "default" simply one, for minimal gob based 
display? I mean - it should not be imo problematic to start ahead 
with displaying simple gob. I see no reason, why user should use 
some mysterious view/as-is, or cryptic append system/view/screen-gob 
win, to get basic gob display. I hope 'view and especially very badly 
designed 'unview will be reworked ...
Henrik
28-Dec-2010
[4833]
View is scheduled for a rewrite. It doesn't fulfill many other requirements, 
so this is going to change.
DideC
28-Dec-2010
[4834]
In RMA A110, this simple lines gives error too :


boxg: make gob! [offset: 20x20 size: 320x320 draw: [pen red box 10x10 
317x317]]
view boxg

** Script error: expected command! not pen
** Where: show view
** Near: show window if all [
    not opts/no-wait 1 = length? screen...
Henrik
28-Dec-2010
[4835]
DideC, try a tuple for the pen.
DideC
28-Dec-2010
[4836x3]
(but another window is opened, empty !)
tuple! : same thing.
I'am with Pekr here : "view make gob! [blah blah]" must work !
Henrik
28-Dec-2010
[4839]
IMHO VIEW should be able to view any datatype, but that is something 
we'll look at when rewriting it.
DideC
28-Dec-2010
[4840x2]
What I want to do is to make a box with an Image as borer pen. Not 
able to do it with R2 nor R3 (see 'View group).
borer=border
Pekr
28-Dec-2010
[4842]
DideC: to progress, please use the solution I outlined: http://www.rebol.com/r3/docs/view/gobs.html#section-13
- as you can see, it was supposed to work under Carl's GUI, but it 
somehow broke with further developments ...