RE: Re[2]: [cgmo-webcgm] Need help with WebCGM Events!

["Ulrich Laesche" <ulrich@ematek.de>]

Hi Benoit,

Attached is the currently available description of the MetaWeb API.  It is
quite coarse and incomplete but it should answer to some of your questions.
Please find additional answers below.

Thanks and regards
Ulrich


-----Original Message-----
From: Benoit Bezaire [mailto:benoit@itedo.com]
Sent: Mittwoch, 16. Juni 2004 03:22
To: CGM Open WebCGM TC
Subject: Re[2]: [cgmo-webcgm] Need help with WebCGM Events!

Hi Ulrich,

Thank you for the examples.  You claim test_API_4 to be academic, but
it is imho very interesting (i.e., it helps).

The examples show at least 5 events (onclick, ondlclick, onmousemove,
onmouseover, onmouseout); which is quite inline with what we're aiming
for.  Do you have other events, maybe keyboard events?

The 'event' is interesting... I can see that you have altKey, button,
ctrlKey, shiftKey, clientX, clientY and srcElement?  Is there anything
else on 'event'?  Is that defined on a single interface or multiple
interfaces, ex: interface Event{}, interface UIEvent : Event{},
interface MouseEvent : UIEvent{}?

UL --> This is defined on a single interface.

Another question that comes to mind is if you are always listening at
the 'viewer' level? (i.e., for=viewer event=onclick).  Can someone,
using your API, listen on a specific APS instead.  An equivalent SVG
example would be (viewer level - <svg onclick="alert('viewer
level')"..., APS level - <g onclick="alert('APS level') ...).

UL --> So far, we are always listening at the viewer level.

Are clientX/Y expressed in pixels or in VDC?

UL --> Pixels.

Is the following syntax:
<script language="JScript" for=viewer event=onclick>
  EventHandler(1, document.viewer.event);
</script>
IE specific?  I wasn't aware of the 'for=viewer' functionality...  I
guess I'm wondering how an implementation works around calls to
'addEventListener'?  Can you comment on this?

UL --> I believe, this is IE specific.  In general, though we have some of
the discussed functionality in place already, certainly a lot of work will
be required to achieve an interoperable and platform independent
implementation.

Sorry for all the questions, but things like this need to be sorted
out if we want to come up with a solid specification.

Many thanks,

--
 Benoit   mailto:benoit@itedo.com


Tuesday, June 15, 2004, 2:37:52 PM, Ulrich wrote:

UL> Hello Benoit,

UL> Attached are two samples from the MetaWeb API (& sample CGM file, but
you
UL> could use whatever version 4 file you want).  test_API_4 utilizes most
of
UL> the events we have implemented into MetaWeb already.  This sample is
quite
UL> academic (a better word for useless) though.  test_API_5 shows how we
UL> implemented highlighting of a certain Application Structure.

UL> Hope this helps and best regards
UL> Ulrich


UL> ----- Original Message -----
UL> From: Benoit Bezaire <benoit@itedo.com>
UL> To: CGM Open WebCGM TC <cgmo-webcgm@lists.oasis-open.org>
UL> Sent: Monday, June 14, 2004 9:01 PM
UL> Subject: [cgmo-webcgm] Need help with WebCGM Events!


>> Hi all,
>>
>>   I'm stuck on the Event interfaces :-|
>>
>>   I need to know why events are needed in the WebCGM DOM?  I need
>>   more examples of what people want to do?
>>
>>   I'm asking since (in my opinion), the DOM Events Level 2 spec is a
>>   fairly complex thing to implement.  I think we have to scale it down
>>   or we won't get any interoperability between vendors.  There are
>>   many interfaces within the DOM Events and I'm trying to determine
>>   which one are needed for WebCGM.
>>
>>   So far, I've only heard about one use case and it is this one (along
>>   these lines anyway):
>>
>>   - A user clicks on an APS within an WebCGM illustration, the script
>>   extracts the ID of the clicked APS and goes to the 'outside' to
>>   gather more information about given object (i.e., part).
>>
>>   What else do people want to do?
>>
>>   Could I get an example how someone would use the new highlight
>>   function we just added?
>>
>>   How are we expecting authoring tools (if we are) to take advantage
>>   of WebCGM Events?
>>
>>   Do any of the proprietary APIs provide any events functionality
>>   (click, mouseup, mousedown, mouseover, onload etc...)?
>>
>>   Thanks,
>>
>> --
>>  Benoit                 mailto:benoit@itedo.com
>>

MetaWeb 2.2 DOM.doc