Re[2]: [cgmo-webcgm] DOM questions and implementation feedback

[Benoit Bezaire <benoit@itedo.com>]

Wednesday, August 25, 2004, 4:36:50 PM, David wrote:

CDW> I guess I'll weigh in on a couple of Benoit's questions...I
CDW> don't see much traffic from the vendor side though.

BB>>   4) What happens if a user changes the raster-intensity of a
BB>>   black & white image?  Does an implementation have to convert the black
BB>>   & white image to grayscale before changing the intensity? Or is this
BB>>   functionality only intended for grayscale and color images and
BB>>   therefore has no effect on black & white images?

CDW> I guess I would expect the black to gray? to de-emphasize that portion?
I agree with you.  It just has to work or else users will be surprised.

BB>>   1) Are APS style attributes cumulative or not?  Example:
BB>>   - assume we have a rectangle filled with black.
BB>>   - we set it to red by calling setStyleAttr( "fill-color", "#FF0000" );
BB>>   - we then set it to a relative color using setStyleAttr(
BB>>   "fill-color", "50%" );

CDW> Good question...without thinking too much about it, I would
CDW> expect the transiant behavior of an APS attribute set through the
CDW> DOM to revert to the original value when a subsequent call to the
CDW> DOM is made w.r.t that APS?
Ok, I don't have a problem with that.  The wording in the spec just
has to be very clear.  If we don't go with this approach, I'm afraid
we'll be increasing implementation time.

BB>>   2) Is the style attribute "fill-color" suppose to fill objects that
BB>>   don't already have a fill-color?   If yes, what does WebCGM say
BB>>   about filling non-closed objects?  calling setStyleAttr(
BB>>   "fill-color", "50%" ) on a non-filled object should do what?

CDW> I would rule that a call to the DOM fill attribute does not
CDW> change the interior style of any of the closed figures in an APS.
CDW> A circle with Interior Style of empty does not get filled if its
CDW> containing APS is called with a fill-color style attribute.
Dave, just to make sure I'm on the same page you are; could you
explain to me when fill-color has an effect?

BB>>   3) Since WebCGM only allows for restricted text elements, what is
BB>>   the usefulness of changing the font-size? ie, it can't exceed the
BB>>   box height?!

CDW> This is a question that occurred to me when we initially
CDW> talked about it in the Cleveland meeting.  Dieter was the one
CDW> that introduced the change of font size.  I think the restricted
CDW> text box ends up getting  in the same was as the character height
CDW> does??
It would be good to hear what others think on this one?  The spec will
have to be very clear here.  Some options could be:

1) Increase RTEXT BBox by percentage (but how to you place the new
box).
2) Increase glyph size once layout algorithm is done based on original
values (but the glyphs would overlap)
3) Determine text baseline according to original values, but compute
text layout based on new values (I think this one will give the best
result, but not sure.)

CDW> I'll let the vendor community address the following implmenetation questions.
We haven't heard from vendors lately... do you guys have any questions
about the spec?  or the implementation?

-- 
 Benoit   mailto:benoit@itedo.com

CDW> thx...dave

BB>>   On to implementation feedback...

BB>>   i) As I've said in the last conference call, the metafileDescription
BB>>   attribute on the Picture interface doesn't make much sense to me.  I
BB>>   think it is really hard for a script writer to use the returned
BB>>   value.

BB>>   I would like to propose that we change the Metafile interface to:
BB>>   interface Metafile {
BB>>     readonly attribute Picture         firstPicture;
BB>>     readonly attribute DOMString       metafileID;
BB>>     readonly attribute DOMString       ProfileId;
BB>>     readonly attribute DOMString       ProfileEd;
BB>>     readonly attribute usigned short   metafileVersion;
BB>>              attribute DOMString       src;
BB>>   };
BB>>   OR
BB>>   interface Metafile {
BB>>     readonly attribute DOMString       metafileDescription; // returns clearText value
BB>>     readonly attribute Picture         firstPicture;
BB>>     readonly attribute DOMString       metafileID;
BB>>     readonly attribute DOMString       ProfileId;
BB>>     readonly attribute DOMString       ProfileEd;
BB>>     readonly attribute usigned short   metafileVersion;
BB>>              attribute DOMString       src;
BB>>   };
BB>>   feedback would be appreciated.

BB>>   ii) We have some methods in the WebCGM DOM that take DOMStringList
BB>>   as input parameters but we have no methods for creating a DOMStringList
BB>>   object or to append/remove DOMStrings from DOMStringList objects.
BB>>   The DOMStringList interface will need to be modified.  And we will
BB>>   also have to find an interface to add a createDOMStringList()
BB>>   method.

BB>>   I haven't heard from the group in a few days regarding the
BB>>   ecmascript binding request; should I assume that people have started
BB>>   implementing without it or is this still an open issue?

BB>>   Regards,