[jdev] Whiteboard.

Heiner Wolf wolf at bluehands.de
Fri Jun 4 12:31:21 CDT 2004


there are 3 additions. 

1. Add optional <subject/> and <body/> to the <path/> for 
   annotations (see TEXT).
2. Add optional shape-attribute for path with values like: 'rect',
   'pointer' (see SHAPE HINT).
3. Add an optional uri-attribute for DOM-based positioning

The ALTERNATE POSITIONING is only for positioning above an HTML DOM 
window. So probably ony the first to apply for whiteboarding in general.

  I added a text element. I know the arguments agains text:
    - Text is difficult because of fonts and 
    - Assumed JEP-113 re-uses SVG and assumed JEP-113 is simple. Then 
      text in general is ruled out, because SVG-text is complex, which 
      the simplicity assumption.

  However, as you wrote: typical karma settings make path based text 
  impossible. If we want simple text then we must deviate from SVG. Here

  is what I have: I do not really need text as a graphical design
  element, but as an annotation. So, text is rather an opaque rectangle 
  with text

  inside. I am using:
    <text x=1 y=2 w=30 h=40 stroke=#000000 stroke-width=5>Text</text>
  The attributes describe the rectangle. The payload text has no styles 
  at all yet. While I am writing I just discover, that it might be nice 
  to merge the <text/>, which is basically a rectangle, with the path 
  element, so that any <path/> can have a payload Text. Maybe like
  <message/> with <subject/> and <body/> sub-tags. I would not define 
  where the annotation is attached to the path. That's up to the 
  It is not a content element, like SVG-text. 

  I also implemented pointers, which are just paths with a fixed shape.
  But for the implementation it was nice to know that it is a pointer. 
  The shape is fixed. It can not be changed accidentally. The hotspot 
  is always at the tip of the pointer (arrow). 
  I implemented a rectange to frame things. It is a path, but it is nice

  for the implementation to 'know' that it is a rectangle. Moving a
  point of the path will keep the rectangle shape by adjusting other 
  points. So, I propose a 'shape' hint for the <path/>
  The shape-attribute also helps to position the annotation
  My whiteboard draws on the web page where people meet (Peter, if you
  read this: yes, I am talking about the LLuna project). 
  For the whiteboard on the web page I added a positioning relative to
  DOM elements of the underlying browser window. I use a uri-attribute 
  for the path. The uri-attribute overrides absolute coordinate based
  It looks like: 
  This means the position is pixel (225,98) relative to the element
  which is the 1st IMG in the 2nd DIV of the 1st BODY tag. There is 
  usually only one, but of course, I keep the index for consistency.
  BTW: the URI refers to a pixel. Is a pixel a resource in the URI
  Expressing the absolute URI including the URL of the document:
  There is a frameset issue. Each frame has a complete DOM. The uri is

  using one DOM as a start, the switching to another DOM, if a FRAME
  comes in the way.

Dr. Klaus H. Wolf
bluehands GmbH & Co.mmunication KG
+49 (0721) 16108 75
LLuna: Jabber enabled virtual presence on the web / http://www.lluna.de/
Galactic developments: Open source future history /

> -----Original Message-----
> From: Rodolfo Gonzalez Gonzalez 
> [mailto:rodolfo at equinoxe.g-networks.net]
> Sent: Friday, June 04, 2004 6:10 PM
> To: Heiner Wolf
> Subject: RE: [jdev] Whiteboard.
> On Fri, 4 Jun 2004, Heiner Wolf wrote:
> > Hi,
> Hello Heiner,
> > I implemented the JEP-113 in LLuna (www.lluna.de). I needed 
> a simple WB
> > protocol for Jabber and JEP-113 is as good as anything 
> (simple) I would
> > dream up myself. So there was no point in re-inventing. I made some
> > (compatible) extensions and sent them to the author. I 
> don't know what
> > he did with my comments.
> It sounds like a good choice. Is there anyway to share those 
> extensions? I
> didn't know about LLuna, but it looks great.
> Thanks in advance.
> Rodolfo.

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